Arctic Sea Ice : Forum

Cryosphere => Arctic sea ice => Topic started by: Lord M Vader on March 13, 2020, 10:24:24 PM

Title: The 2020 melting season
Post by: Lord M Vader on March 13, 2020, 10:24:24 PM
The last couple of days have seen a decline in the sea ice extent in Arctic, mostly confined to peripheral areas. Whether this downward trend is signaling the "onset" of the melting is an open question. However, we are in the middle of March and this year the upcoming weeks will probably be terribly slow for most of us. So, if Neven is OK with maning an exception for this year I hope we can start the discussions about the 2020 melting season.

The strong polar vortex that bottled up the cold air over the central Arctic basin should have strengthened the ice enough to make the 2020 minimum end up higher than the last few years. At least if we Have a moderately bad summer.

I hope everyone in here will be with us through the whole season and many more years ahead. Stay safe out there!

//LMV

<edit Neven: I don't have time to follow current events in the Arctic, so I can't assess whether it's too early for this thread or not, which means I'll leave it open. I did adjust the title though. If there's a second max, this is on you, LMV.  ;) >
Title: Re: The 2020 melting season
Post by: PragmaticAntithesis on March 14, 2020, 06:11:11 PM
Alright, I finally found the actual thread. Sorry about creating a clone! >_<
Title: Re: The 2020 melting season
Post by: kassy on March 14, 2020, 06:20:29 PM
Thanks! Also there are usually several MS threads so you have just made your contribution to the tradition.  :)

Title: Re: The 2020 melting season
Post by: kassy on March 14, 2020, 06:25:02 PM
Also

Has anyone notices that there is a large "valley" in the Fram strait in the DMI thickness map? If that's accurate then the ice near the pole could be unusually weak this year.

(https://forum.arctic-sea-ice.net/proxy.php?request=http%3A%2F%2Fpolarportal.dk%2Ffileadmin%2Fpolarportal%2Fsea%2FCICE_map_thick_LA_EN_20200311.png&hash=4275cdc06117ae13f3c3ab398376d7c6)

That does not look like a great set up. Very weak on the siberian side.
Title: Re: The 2020 melting season
Post by: Stephan on March 14, 2020, 08:30:17 PM
This melting season starts with a higher extent than most of the years before. The last year with a higher extent value than 2020 (see Juan's post in the Sea Ice Area and Extent thread) was 2014.
So let's see what 2020 brings...


PS: My Post # 1.000
Title: Re: The 2020 melting season
Post by: blumenkraft on March 14, 2020, 08:37:01 PM
Congrats, Stephan! :)

2012 was higher BTW and had a later maximum than in 2020.
Title: Re: The 2020 melting season
Post by: HapHazard on March 14, 2020, 08:52:58 PM
Congrats, Stephan! :)

2012 was higher BTW and had a later maximum than in 2020.

Indeed! Predicting the minimum extent based on current maximum isn't really feasible. There's a bunch of other indicators I'd consider much more valuable to glean info from. But this far out, there's just too many dice rolls between now & then.

That said, based on my own top-secret formula I predict we'll finish top-3 in lowest min extent.  ;)
Title: Re: The 2020 melting season
Post by: blumenkraft on March 14, 2020, 09:08:28 PM
Well, what's your top-secret formula then? I will tell no one else, i promise. :P ;D
Title: Re: The 2020 melting season
Post by: HapHazard on March 14, 2020, 11:50:08 PM
I will only divulge that it involves Green Spot Irish Whiskey.
Title: Re: The 2020 melting season
Post by: Freegrass on March 14, 2020, 11:56:17 PM
Did you guys really start a new melting thread without posting the Slater prediction?  ;D

We're coming in very low...

https://cires1.colorado.edu/~aslater/SEAICE/
Title: Re: The 2020 melting season
Post by: Tom_Mazanec on March 15, 2020, 01:07:00 AM
Will possible aerosol reduction from covid-19 economic decline affect this year’s minimum?
Title: Re: The 2020 melting season
Post by: PragmaticAntithesis on March 15, 2020, 01:41:02 AM
Will possible aerosol reduction from covid-19 economic decline affect this year’s minimum?

I wouldn't be surprised if it causes an increase. The lack of soot in the air will give the ice higher albedo, especially in the upcoming freezing season. [sarcasm]Time to start the 2020/2021 freezing thread?[/sarcasm] This may cause the ice to be much more resilient, especially next year, and could delay the eventual BOE.

Also, look at where the temperature increase caused by removing aerosols is coming from: it's increasing the effective power of the sun by unblocking light instead of decreasing the amount of heat escaping from Earth like the usual greenhouse effect. This probably means all the additional heat is going to end up at the equator (which sea ice doesn't care about), not the poles.
Title: Re: The 2020 melting season
Post by: NotaDenier on March 15, 2020, 03:48:39 AM
Will possible aerosol reduction from covid-19 economic decline affect this year’s minimum?

I wouldn't be surprised if it causes an increase. The lack of soot in the air will give the ice higher albedo, especially in the upcoming freezing season. [sarcasm]Time to start the 2020/2021 freezing thread?[/sarcasm] This may cause the ice to be much more resilient, especially next year, and could delay the eventual BOE. Also, look at where the temperature increase caused by removing aerosols is coming from: it's increasing the effective power of the sun by unblocking light instead of decreasing the amount of heat escaping from Earth like the usual greenhouse effect. This probably means all the additional heat is going to end up at the equator (which sea ice doesn't care about), not the poles.

The studies after 9/11found that contrails decreased daytime temps and increased night time temps. When contrails are reduced (like right now) the daytime temps rise more then night time temps decrease. This is because it matters when the contrails form. Because most flying is during the day the daytime temps are suppressed more by the cloud formation. So the current flying situation will provide more data to the weather scientists.

Somewhat related I believe “smog” from China and India (among the biggest producers of SO2)  also reduces incoming solar radiation. So if we are in a six month world wide recession is it not possible we will see one of the hottest years on record without an El Niño?

On the other hand oil is really cheap now...

I’d really like some of the professional weather experts to comment on this if they have time.
Title: Re: The 2020 melting season
Post by: Freegrass on March 15, 2020, 03:01:10 PM
The studies after 9/11found that contrails decreased daytime temps and increased night time temps. When contrails are reduced (like right now) the daytime temps rise more then night time temps decrease. This is because it matters when the contrails form. Because most flying is during the day the daytime temps are suppressed more by the cloud formation. So the current flying situation will provide more data to the weather scientists.

Somewhat related I believe “smog” from China and India (among the biggest producers of SO2)  also reduces incoming solar radiation. So if we are in a six month world wide recession is it not possible we will see one of the hottest years on record without an El Niño?

On the other hand oil is really cheap now...

I’d really like some of the professional weather experts to comment on this if they have time.
I wanted to point you to the Black Carbon thread, but that doesn't exist yet?

It's important to note that black carbon actually warms the planet. Here's a little info, but I think this is not the place to discuss this?

Quote
In climatology, black carbon is a climate forcing agent. Black carbon warms the Earth by absorbing sunlight and heating the atmosphere and by reducing albedo when deposited on snow and ice (direct effects) and indirectly by interaction with clouds, with the total forcing of 1.1 W/m2.[2] Black carbon stays in the atmosphere for only several days to weeks, whereas carbon dioxide (CO

https://en.wikipedia.org/wiki/Black_carbon

Direct effect Black carbon particles directly absorb sunlight and reduce the planetary albedo when suspended in the atmosphere.

Semi-direct effect Black carbon absorb incoming solar radiation, perturb the temperature structure of the atmosphere, and influence cloud cover. They may either increase or decrease cloud cover under different conditions.[66]

Snow/ice albedo effect When deposited on high albedo surfaces like ice and snow, black carbon particles reduce the total surface albedo available to reflect solar energy back into space. Small initial snow albedo reduction may have a large forcing because of a positive feedback: Reduced snow albedo would increase surface temperature. The increased surface temperature would decrease the snow cover and further decrease surface albedo.[67]

Indirect effect Black carbon may also indirectly cause changes in the absorption or reflection of solar radiation through changes in the properties and behavior of clouds. Research scheduled for publication in 2013 shows black carbon plays a role second only to carbon dioxide in climate change. Effects are complex, resulting from a variety of factors, but due to the short life of black carbon in the atmosphere, about a week as compared to carbon dioxide which last centuries, control of black carbon offers possible opportunities for slowing, or even reversing, climate change.[67][68][69]

Radiative forcing
Estimates of black carbon's globally averaged direct radiative forcing vary from the IPCC’s estimate of + 0.34 watts per square meter (W/m2) ± 0.25,[70] to a more recent estimate by V. Ramanathan and G. Carmichael of 0.9 W/m2.[71]

The IPCC also estimated the globally averaged snow albedo effect of black carbon at +0.1 ± 0.1 W/m2.

Based on the IPCC estimate, it would be reasonable to conclude that the combined direct and indirect snow albedo effects for black carbon rank it as the third largest contributor to globally averaged positive radiative forcing since the pre-industrial period. In comparison, the more recent direct radiative forcing estimate by Ramanathan and Carmichael [71] would lead one to conclude that black carbon has contributed the second largest globally averaged radiative forcing after carbon dioxide (CO2), and that the radiative forcing of black carbon is “as much as 55% of the CO2 forcing and is larger than the forcing due to the other greenhouse gasses (GHGs) such as CH4, CFCs, N2O, or tropospheric ozone.”
Title: Re: The 2020 melting season
Post by: kassy on March 15, 2020, 04:18:51 PM
So if we are in a six month world wide recession is it not possible we will see one of the hottest years on record without an El Niño?

We had one last year without a recession...
Title: Re: The 2020 melting season
Post by: gandul on March 15, 2020, 04:26:05 PM
Will possible aerosol reduction from covid-19 economic decline affect this year’s minimum?

I wouldn't be surprised if it causes an increase. The lack of soot in the air will give the ice higher albedo, especially in the upcoming freezing season. [sarcasm]Time to start the 2020/2021 freezing thread?[/sarcasm] This may cause the ice to be much more resilient, especially next year, and could delay the eventual BOE.

Also, look at where the temperature increase caused by removing aerosols is coming from: it's increasing the effective power of the sun by unblocking light instead of decreasing the amount of heat escaping from Earth like the usual greenhouse effect. This probably means all the additional heat is going to end up at the equator (which sea ice doesn't care about), not the poles.
This theory of yours is peculiar. So lack of aerosols caused by depressed economic activity will lead to a small cooling?
I would expect a small short-duration increase of global temperatures beyond what is the current trend, and indirect (small) negative impact on sea ice.
Unless the current crisis leads to a real depression...
Title: Re: The 2020 melting season
Post by: grixm on March 15, 2020, 06:09:51 PM
Some fast ice in Laptev and Kara is starting to crack. Maybe just because of drift, not melting. Click to play.
Title: Re: The 2020 melting season
Post by: blumenkraft on March 15, 2020, 06:39:27 PM
If i interpret the weather correctly, the Fram export could be rampant in the upcoming days.

This week's ice drift map.  8)
Title: Re: The 2020 melting season
Post by: blumenkraft on March 15, 2020, 06:40:54 PM
Sunday to Sunday movie of the 7-day mean temperature anomalies.
Title: Re: The 2020 melting season
Post by: blumenkraft on March 15, 2020, 06:41:52 PM
And the Fram export via SAR.
Title: Re: The 2020 melting season
Post by: gerontocrat on March 15, 2020, 08:29:59 PM
It's windy in the Arctic Ocean and surrounding land today.
Looks like staying that way for a few days.

from Nullschool 15 March.
Title: Re: The 2020 melting season
Post by: PragmaticAntithesis on March 15, 2020, 10:23:28 PM
Wow, that is a lot of Fram export. Is there any precedent for this much ice going down the drain early in melt season, and if so, how bad was the extent that year?
Title: Re: The 2020 melting season
Post by: P-maker on March 16, 2020, 03:18:51 AM
PA, no precedent.

But, previous estimates were that prior to the first BOE in the Arctic, the Greenland Sea ice extent would hit one million square kms.

Let's see if we get there this year...
Title: Re: The 2020 melting season
Post by: jdallen on March 16, 2020, 05:06:15 AM
Will possible aerosol reduction from covid-19 economic decline affect this year’s minimum?

I wouldn't be surprised if it causes an increase.
<snip>
Counter intuitive and I think possibly counter factual as well.

Aerosols tend to reduce insolation, and the last few years, we've had far more particulates at high latitude introduced by wildfires than any sort of human activity.  Compared to that, a drop in human black carbon won't make a lot of difference, I expect.

Also big... assuming it does reduce consumption, will be a reduction in SO2, which we know produces an increase at energy arriving at sea level.

Now, as to albedo - particulates at this point really haven't produced major effects on the ice.  Open water, melt ponds and bare ground really remain the primary drivers in determining how much direct insolation gets picked up north of 67 degrees latitude.

We already have an anomaly there with European snow cover.  I'll have to check numbers, but my suspicion is we'll see a fairly fast drop in snow pack coverage.
Title: Re: The 2020 melting season
Post by: binntho on March 16, 2020, 11:48:46 AM
Also big... assuming it does reduce consumption, will be a reduction in SO2, which we know produces an increase at energy arriving at sea level.

So I assume you are saying that a decrease in SO2 causes an increase in energy reaching the surface? My first reading of this sentence implied the opposite ...
Title: Re: The 2020 melting season
Post by: binntho on March 16, 2020, 11:49:43 AM
PA, no precedent.

But, previous estimates were that prior to the first BOE in the Arctic, the Greenland Sea ice extent would hit one million square kms.

Let's see if we get there this year...

What previous estimates?
Title: Re: The 2020 melting season
Post by: Freegrass on March 16, 2020, 01:26:41 PM
Snow is disappearing rapidly...

https://go.nasa.gov/38RadpN
Title: Re: The 2020 melting season
Post by: binntho on March 16, 2020, 02:15:02 PM
Snow is disappearing rapidly...

https://go.nasa.gov/38RadpN

I'm not seeing any real difference between now and previous years. Easy to scroll between the years for comparison.
Title: Re: The 2020 melting season
Post by: blumenkraft on March 16, 2020, 02:21:35 PM
Perhaps not the area at the link, but there is indeed less snow at the European side. This is taken from Nico Sun's website. Red areas on the map means less snow.
Title: Re: The 2020 melting season
Post by: P-maker on March 16, 2020, 02:57:57 PM
Binntho:

 
Quote
What previous estimates?


That would be my own estimates in a debate some years ago with a fellow discussant on this site.

My main argument at that time was that in order to reach one mio. sq. kms in the Arctic, spring had to come up with an extraordinary export of at least one mio. sq. kms through Fram Strait to the Greenland Sea (since Nares Strait is not delivering nearly enough at this time of year).

You have yourself delivered a splendid example of a record year (1947) when the Greenland sea in April was nearly full of Arctic sea ice: https://www.pmel.noaa.gov/rediscover/datalist/phpFileTree/dmi_sea_ice_maps/1947/1947.pdf

In those days however, the Arctic was full to the brim of multi-year ice, thus filling up the Greenland Sea was much easier.

Natural variability in the Arctic melting of sea ice due to freak weather may deliver a couple of mio. sq. kms at best (or worst), which will eventually get us under 1 mio. sq. kms in August/September/October. Thus, we will not get below the threshold proposed by some in the IPCC, unless we see extraordinary spring export figures through the Fram.
Title: Re: The 2020 melting season
Post by: binntho on March 16, 2020, 03:05:40 PM
Perhaps not the area at the link, but there is indeed less snow at the European side. This is taken from Nico Sun's website. Red areas on the map means less snow.

All the red areas are far to the south of the Arctic, and unlikely to influence temperatures there. But it would not surprise me if parts of Siberia had less snow than usual, the temps there have been extremely high this winter.

But if less snow is to make any difference, then there has to be significant difference in insolation in the Arctic itself. This is not happening yet, but remains one of the things to look out for.
Title: Re: The 2020 melting season
Post by: binntho on March 16, 2020, 03:10:47 PM
Binntho:
 
Quote
What previous estimates?

That would be my own estimates in a debate some years ago with a fellow discussant on this site.

Good to know.

Quote
You have yourself delivered a splendid example of a record year (1947) when the Greenland sea in April was nearly full of Arctic sea ice: https://www.pmel.noaa.gov/rediscover/datalist/phpFileTree/dmi_sea_ice_maps/1947/1947.pdf

I wasn't aware that 1947 was a record year ... what records did it break?
Title: Re: The 2020 melting season
Post by: blumenkraft on March 16, 2020, 03:37:02 PM
(since Nares Strait is not delivering nearly enough at this time of year

This would be zero so far to be pricise. The NS is frozen over and there is a stable southern arch at the moment.

I'm guessing here, but NS export could be extremely low this year. The temperatures in the area have been lower than average during the winter and the arch might break late in the year or not break at all.
Title: Re: The 2020 melting season
Post by: blumenkraft on March 16, 2020, 03:40:38 PM
and unlikely to influence temperatures there

You might be right, but don't forget the albedo effect. I wouldn't dismiss that so easily.
Title: Re: The 2020 melting season
Post by: Freegrass on March 16, 2020, 03:48:04 PM
Easy to scroll between the years for comparison.
True. I keep forgetting that.
Title: Re: The 2020 melting season
Post by: P-maker on March 16, 2020, 05:13:53 PM
Binntho,

Please try to goggle "1947 record-breaking" and see what comes up. Europe was record-warm mainly during the summer and North America had record-Breaking snowfall in December. Many more 1947 records were beaten during the last few years, so maybe the Arctic was weird too, although few measurements were taken just after WW II.
Title: Re: The 2020 melting season
Post by: binntho on March 16, 2020, 05:59:33 PM
Binntho,

Please try to goggle "1947 record-breaking" and see what comes up. Europe was record-warm mainly during the summer and North America had record-Breaking snowfall in December. Many more 1947 records were beaten during the last few years, so maybe the Arctic was weird too, although few measurements were taken just after WW II.

Really. How interesting. I thought perhaps 1947 broke the record of not having broken any records. But the reliability of the "previous estimates" is rapidly clarifying.
Title: Re: The 2020 melting season
Post by: jdallen on March 17, 2020, 02:33:22 AM
Also big... assuming it does reduce consumption, will be a reduction in SO2, which we know produces an increase at energy arriving at sea level.

So I assume you are saying that a decrease in SO2 causes an increase in energy reaching the surface? My first reading of this sentence implied the opposite ...
Correct.  SO2 in the atmosphere reduces incoming insolation.  Reduce it, and you get a small uptick in insolation reaching the surface.
Title: Re: The 2020 melting season
Post by: The Walrus on March 17, 2020, 04:39:21 PM
Also big... assuming it does reduce consumption, will be a reduction in SO2, which we know produces an increase at energy arriving at sea level.

So I assume you are saying that a decrease in SO2 causes an increase in energy reaching the surface? My first reading of this sentence implied the opposite ...
Correct.  SO2 in the atmosphere reduces incoming insolation.  Reduce it, and you get a small uptick in insolation reaching the surface.

Yes, SO2 reduces incoming insolation, resulting in a cooling effect.  Oftentimes, SO2 emissions are accompanied by carbon black (i.e. soot).  This has a warming effect.  Coal burning releases CO2, SO2, and carbon black, with a net warming effect.  So-called cleaner fuels have reduced sulfur content, such that the aerosol effect is likely less than the greenhouse effect.
Title: Re: The 2020 melting season
Post by: Glen Koehler on March 17, 2020, 05:52:10 PM
     As I understand it -- SO2 primarily has an effect when large volcanic eruptions, esp. those near the equator, inject large amounts of SO2 into the stratosphere where they can persist for an extended period.  Lower height eruptions are less likely to have a significant effect on incoming solar radiation and global average surface temperature because the SO2 falls out rather quickly.

   The most recent years when volcanic SO2 aerosols had a major effect on temperature were 1982-1983 and 1992-1993.  There is about a 7 month lag between the measured global average aerosol level and an effect on global average surface temperature.  The temperature suppression in those years was on the order of 0.1 to 0.2 C below what the temperature would have likely been without the aerosol influence. 

    The “Year without a summer” in the Northeastern US in 1816 was caused in part by the Mt. Tambora eruption in 1815.  There was snow in Dennysville Maine on June 6, 1816.  Massachusetts had a severe frost in every month.  Less than a quarter of the corn crop was harvestable.  This was all caused by a decrease of average global temperatures of 0.4–0.7 °C (0.7–1.3 °F), and a decrease of average land temperature by about 1C.

    Monthly aerosol level is updated by 11th day of the following month at https://www.esrl.noaa.gov/gmd/webdata/grad/mloapt/mauna_loa_transmission.dat (https://www.esrl.noaa.gov/gmd/webdata/grad/mloapt/mauna_loa_transmission.dat) 
Values are transmission through atmosphere, thus lower values = more aerosol blockage.  Values above 0.9160 are unlikely to cause a noticeable temperature effect.
Title: Re: The 2020 melting season
Post by: Glen Koehler on March 18, 2020, 07:48:13 PM
    Given the importance of snow cover ...
 (see for ice dynamics https://forum.arctic-sea-ice.net/index.php/topic,2906.msg254713.html#msg254713 (https://forum.arctic-sea-ice.net/index.php/topic,2906.msg254713.html#msg254713) )
   

   ... is there a status report of how snow cover on top of the ASI at this time compared to same date in previous years, and what that suggests about the 2020 melt season?  I know Siberia has reduced snow cover and that has consequences for spring warm up.  But what about the snow cover directly on the ASI?  What is the current situation for that?

Title: Re: The 2020 melting season
Post by: interstitial on March 18, 2020, 09:51:44 PM
snow cover topic
https://forum.arctic-sea-ice.net/index.php/topic,2876.0.html (https://forum.arctic-sea-ice.net/index.php/topic,2876.0.html)
Title: Re: The 2020 melting season
Post by: El Cid on March 18, 2020, 09:57:51 PM
 
 This was all caused by a decrease of average global temperatures of 0.4–0.7 °C (0.7–1.3 °F), and a decrease of average land temperature by about 1C.

   
Let's not forget that if global land temps go down 1 C that is oftentimes 2-3 C for NH mid and high-latitudes plus cold outbreaks with late frosts that can kill any plants   
Title: Re: The 2020 melting season
Post by: Glen Koehler on March 18, 2020, 11:51:50 PM
   Thanks, but instead of NH snow cover, I'm wondering about the snow cover directly on the ASI.  The MOSAIC scientist in the video blumenkraft posted says that snow quality (albedo, roughness, stratigraphy, crystal structure) has a huge effect on the atmosphere-ice interaction and melt season progression.  I suspect that these relationships are only beginning to be understood and that the scientists need more time to collect and crunch data before reaching any conclusions about the current situation.  Thus, there may not be an answer to my question at this time. 

    Snow cover characteristics on top of the ASI could be a missing factor in melt season variability that (in addition to weather, melt ponds, drift currents etc.) makes multi-month ASI prediction difficult.  Stephan shared regressions a month or so ago that showed Extent and Volume in prior months have poor correlation with September minimums.  Basically nil in May, weak in June.  It isn't until July that knowing those values gets you much predictive skill about September.

    Then again, Slater model and some other methods seem to do a halfway decent job of predicting Sept. minimums.  The more I think about this the less I pretend to know!
Title: Re: The 2020 melting season
Post by: PragmaticAntithesis on March 18, 2020, 11:53:03 PM
Let's not forget that if global land temps go down 1 C that is oftentimes 2-3 C for NH mid and high-latitudes plus cold outbreaks with late frosts that can kill any plants

Well, it's a good job the temperatures are going the other way then, right?
Title: Re: The 2020 melting season
Post by: uniquorn on March 19, 2020, 12:40:53 AM
uni-hamburg amsr2-uhh, bering, mar10-17
added wipneus regional extent (https://sites.google.com/site/arcticseaicegraphs/regional), bering, mar17
Title: Re: The 2020 melting season
Post by: tybeedave on March 19, 2020, 08:21:03 PM
Greetings from Midway Georgia,
 I've been lurking here for years, but after some 26 tears online, this the very 1st forum that I have ever joined.  This is my 5th attempt to make a post, so bear with me as i learn the ropes :)
 I've been alarmed by the huge export through Farm and subsequent melting signified by the foam left over from the melting ice in the GS as illustrated by the attached image.
 Also included in the image of some beautiful cloud vortices.  It's too bad that they overlay a field of death for ice

https://worldview.earthdata.nasa.gov/?v=348385.3212968977,-1205274.273347458,1466593.3212968977,-680986.2733474581&p=arctic&t=2020-03-18-T19%3A13%3A07Z (https://worldview.earthdata.nasa.gov/?v=348385.3212968977,-1205274.273347458,1466593.3212968977,-680986.2733474581&p=arctic&t=2020-03-18-T19%3A13%3A07Z)

td

think good thoughts, do good deeds, enjoy good results

Title: Re: The 2020 melting season
Post by: interstitial on March 19, 2020, 10:17:55 PM
Welcome Tybeedave
Title: Re: The 2020 melting season
Post by: Niall Dollard on March 19, 2020, 10:39:11 PM
Welcome TybeeDave and don't be shy !

Re the Fram foam, I wouldnt call it foam. These are strips of sea ice that are pulled off the main pack.

We see it a lot in the Bering Sea where the ice is often thin and can break away easily. Here is an image from the Bering on March 3rd. Strips of ice are very close to St. Paul Island (arrowed). This was about as far as it got this year.

This was more or less predicted by NWS Anchorage (https://tgftp.nws.noaa.gov/data/raw/fz/fzak30.pafc.ico.afc.txt) in their outlook post on Feb 25th. Quote :

...FREEZE-UP OUTLOOK FOR THE BERING SEA...

"There is a 30 percent chance that the sea ice will make it to Saint Paul Island this season. The most likely scenario that would allow sea ice to reach the island is if northerly winds and cold air
persist for several days. If sea ice does reach Saint Paul Island, we expect it to generally be in the form of strips of sea ice that are pulled off the main pack. The northerly winds and cold air would likely have to persist for a couple weeks or more for the main ice pack to reach the island."

Title: Re: The 2020 melting season
Post by: tybeedave on March 19, 2020, 11:49:45 PM
ty interstitial, and ty Niall for the insight, I'm not shy :)

I based my idea on the vision of an ice cube melting in a glass of water.  Except, in the purest of ice and water, a few scummy bubbles are left behind. Add that to my amateur perception of the ice waves (foam) in my image appearing to be moving (in a convex shape) towards the flowing ice.
But I will defer to your experience while I'm self-quarantining and homeschooling :)
td
think good, do good, enjoy good...er, well
Title: Re: The 2020 melting season
Post by: oren on March 20, 2020, 12:13:03 AM
Welcome td.
Title: Re: The 2020 melting season
Post by: El Cid on March 20, 2020, 07:32:52 AM
Let's not forget that if global land temps go down 1 C that is oftentimes 2-3 C for NH mid and high-latitudes plus cold outbreaks with late frosts that can kill any plants

Well, it's a good job the temperatures are going the other way then, right?

Oh yes, it works like that both ways. 3 C global average temperature rise will mean 6-9 C warmer winters in NH midlatitudes and 3-6 degress warmer summers. We will get there pretty soon...
Putin says good, at least Russians will have to buy fewer fur-coats...

(attached map shows 1C global temp anomaly vs 1950-1980 which implies 2-3 C warmer winters in NH mid and high latitude land)
Title: Re: The 2020 melting season
Post by: meddoc on March 20, 2020, 09:15:03 AM

Putin says good, at least Russians will have to buy fewer fur-coats...


What does Trumpeteer say? Politicians all play their part. There was a consensus reached at 2009 G20; it will be Bussiness as Ususal no matter what.
Then, the Yanks turned the tables, starting to deploy their ABMs/ nukes against Russia/ China.
Which clearly means they are not going to adhere to that consensus and just carry on- but trying to get an advantage in the coming collapse.
Title: Re: The 2020 melting season
Post by: kassy on March 20, 2020, 12:55:17 PM
Lets keep to the ice...plenty of threads to talk politics in the subforums.
Title: Re: The 2020 melting season
Post by: Shared Humanity on March 21, 2020, 03:55:26 AM
Lets keep to the ice...plenty of threads to talk politics in the subforums.

Thank you.
Title: Re: The 2020 melting season
Post by: uniquorn on March 21, 2020, 08:35:25 AM
Kaleschke SIC leads (https://twitter.com/seaice_de/status/1221805753050320896), Fram funnel, mar10-21.
Worldview Terra Modis , Svalbard-FJL gap, mar10-20   https://go.nasa.gov/3bcw5O7
click to run
Title: Re: The 2020 melting season
Post by: uniquorn on March 22, 2020, 10:05:15 AM
A large area of the Chukchi Sea looking lightly frozen yesterday. https://go.nasa.gov/3a96hSQ
click for full resolution
Title: Re: The 2020 melting season
Post by: blumenkraft on March 22, 2020, 07:03:25 PM
Sunday is movie time:

Let's start with Fram export.
Title: Re: The 2020 melting season
Post by: blumenkraft on March 22, 2020, 07:04:13 PM
Last week's ice drift map.
Title: Re: The 2020 melting season
Post by: blumenkraft on March 22, 2020, 07:05:11 PM
7-day hindsight mean temperature anomalies.
Title: Re: The 2020 melting season
Post by: uniquorn on March 22, 2020, 08:43:02 PM
That makes it a long time with very little Beaufort gyre movement
osi-saf (http://osisaf.met.no/p/osisaf_hlprod_qlook.php?year=2020&month=01&day=07&action=Today&prod=LR-Drift&area=NH&size=100%25), sep21-mar19

whoi itp112 (https://www.whoi.edu/page.do?pid=165216) drift track (deployed sep2019)
Title: Re: The 2020 melting season
Post by: Wildcatter on March 23, 2020, 02:04:17 AM
Kaleschke SIC leads (https://twitter.com/seaice_de/status/1221805753050320896), Fram funnel, mar10-21.
Worldview Terra Modis , Svalbard-FJL gap, mar10-20   https://go.nasa.gov/3bcw5O7 (https://go.nasa.gov/3bcw5O7)
click to run

Awesome. Can you make another one over the next 5 days? Lot of warmth coming up from the Atlantic, winds, several interesting dynamics at play.

The stratospheric polar vortex is also taking a ton of heat, looks like its going to start splitting/collapsing/whatever it does towards end of winter season over the next week.

Between the fringe ice, Bering, warmth coming up from Atlantic, the next 4-5 days could see 2020 right in the mix of things again. It's also been a very warm Jan-Feb globally.
Title: Re: The 2020 melting season
Post by: tybeedave on March 23, 2020, 08:53:18 AM
I'm very alarmed.
  There is a very important event occurring over the entire arctic currently!

The event is the extreme export if ice thru Fram St. in concert with ice import and bunches of relatively warm P water gushing through the Bering St.

There seems to have been so much export thru Fram, that, the way above normal amounts of warm P water are being sucked into the system.

I think the entire event is being fueled by wind.  I don't remember ever seeing such a persisent strong southerly wind down the Fram.  but, My experience in the wind physics of ice movement is basic, can anyone address what appears to be a >1% shift of the entire ice sheet to oblivion is a week????
Then look at the turbulence that the gushing warm P water has had on the north and south Chukchi Sea. Two large eddys are visible where i bet the salinity levels are high and the surface water temp is above 0C.

  In the attached image of the Bering St, the yellow areas indicate areas of wind caused import and the blue is the direction of the movement of surface turbulence, i think.
I am fearing that this early melting event can hurt the Arctic as a whole as bad as the imfamous 2012 late season wind event.
 
The second image is another focusing on the extreme melting currently occurring in Fram.

td
Title: Re: The 2020 melting season
Post by: oren on March 24, 2020, 04:20:44 AM
On March 6th NSIDC sea ice area was 471k above the 2010s average. 16 days later and the same measure is 23k below its 2010s average. All the extra buffer carefully stashed away by the freezing season has vaporized and it's not even April.
It must always be kept in mind that the last sea ice area is in far peripheral seas, the four B's as I like to call them* which dictate max numbers, but which easily give up their ice once conditions reverse. So one should never draw too many conclusions about the melting season from the max area/extent.
* It's a lie: Baffin, Barents, Bering and (B)Okhotsk.
Title: Re: The 2020 melting season
Post by: Rodius on March 24, 2020, 04:27:33 AM
* It's a lie: Baffin, Barents, Bering and (B)Okhotsk.

Why not just call it very bad BBBO?
Title: Re: The 2020 melting season
Post by: oren on March 24, 2020, 04:56:35 AM
During the cold dark Arctic night one must have some fun to keep one's sanity. Besides, the four B's thing absurdly helps me to recall the names more easily.
Title: Re: The 2020 melting season
Post by: jdallen on March 24, 2020, 06:40:51 AM
On March 6th NSIDC sea ice area was 471k above the 2010s average. 16 days later and the same measure is 23k below its 2010s average.
<snip>
* It's a lie: Baffin, Barents, Bering and (B)Okhotsk.
During the cold dark Arctic night one must have some fun to keep one's sanity. Besides, the four B's thing absurdly helps me to recall the names more easily.
I like it :)

That said, this drop highlights how the change in the quality of the ice is changing how the melt season progresses.

It is less about extent and area.

It is more about age, thickness and volume.

Most of the ice that's appeared this year in the Barents and Bering above and beyond what wasn't there the last few years is barely coherent, and doesn't have any ability to resist weather.

It will likely vanish like morning mist on a hot spring day.


Title: Re: The 2020 melting season
Post by: jdallen on March 24, 2020, 06:43:44 AM
... I also don't like all the yellow I'm seeing in this graphic.  That concentration is a lot lower than I'd like.
Title: Re: The 2020 melting season
Post by: binntho on March 24, 2020, 07:14:26 AM
... I also don't like all the yellow I'm seeing in this graphic.  That concentration is a lot lower than I'd like.

Truly surprising the amount of less-than-full concentration in the Arctic itself.
Title: Re: The 2020 melting season
Post by: uniquorn on March 24, 2020, 12:05:12 PM
An overview of sea ice movement as seen by ascat (https://manati.star.nesdis.noaa.gov/ascat_images/ice_image/msfa-NHe-a-2020083.sir.gif), jan1-mar23
The amsr2 low concentration area in/around the Beaufort correlates quite well with the darker area on ascat but may also be related to the recent heavy cloud cover.
Title: Re: The 2020 melting season
Post by: PragmaticAntithesis on March 24, 2020, 12:13:54 PM
... I also don't like all the yellow I'm seeing in this graphic.  That concentration is a lot lower than I'd like.

Perhaps last year's late freeze of the Chukchi made the ice in that area more vulnerable? In January, the thickness there was almost nonexistent, despite extent having recovered. I've attached the DMI's thickness map for January 1st 2020. Look at all that horribly weak purple in the Chukchi that's been blown into the CAB by Pacific winds.
Title: Re: The 2020 melting season
Post by: Niall Dollard on March 24, 2020, 12:55:56 PM
Re Bremen image and Beaufort.

It didn't look so bad on the 19th compared to 22nd.

I wonder is it sensor related or is that Beaufort thinning real ?
Title: Re: The 2020 melting season
Post by: Freegrass on March 24, 2020, 01:01:25 PM
* It's a lie: Baffin, Barents, Bering and (B)Okhotsk.

Why not just call it very bad BBBO?
Sea 3BO?
Title: Re: The 2020 melting season
Post by: El Cid on March 24, 2020, 01:18:12 PM
Someone did some great charts during the last melting season based on Bremen, average and max thickness. It filtered out the day to day variation. We could use those once again.

However, there really does seem to be serious weakness from the Barents to the Laptev. I would not be surprised to see a record this year (esp. considering aerosols and the snowless winter in Eurasia)
Title: Re: The 2020 melting season
Post by: oren on March 24, 2020, 01:30:01 PM
An overview of sea ice movement as seen by ascat (https://manati.star.nesdis.noaa.gov/ascat_images/ice_image/msfa-NHe-a-2020083.sir.gif), jan1-mar23
The amsr2 low concentration area in/around the Beaufort correlates quite well with the darker area on ascat but may also be related to the recent heavy cloud cover.
Thanks for this uniquorn. A most important animation.
It seems the Fram export was very active this winter, especially towards the end of the animation when the whole thing just slides to the exit. Not a good setup for the melting season.
Title: Re: The 2020 melting season
Post by: ReverendMilkbone on March 24, 2020, 11:43:02 PM
Re Bremen image and Beaufort.

It didn't look so bad on the 19th compared to 22nd.

I wonder is it sensor related or is that Beaufort thinning real ?

Climate Reanalyzer has shown the Beaufort and Bearing seas to be waaayyy warmer than usual over the last several weeks.  Here is today's anomaly;
Title: Re: The 2020 melting season
Post by: Rodius on March 25, 2020, 04:32:05 AM
* It's a lie: Baffin, Barents, Bering and (B)Okhotsk.

Why not just call it very bad BBBO?
Sea 3BO?

That put a smile on my face lol
Title: Re: The 2020 melting season
Post by: oren on March 25, 2020, 06:37:35 AM
March 24th, 2020:
     13,824,816 km2, the 1st century drop of the melting season: -119,374 km2.
     2020 changed from 10th to 4th lowest on record.  :o
Damn!
Admittedly it's mostly random numbers at this point, but this one's a big move. The melting season has started quite vigorously. Should Fram export continue in earnest the random numbers may yet signal something for the summer.

As usual thank you to Juan and Gerontocrat for keeping us up to date on the other thread.
Title: Re: The 2020 melting season
Post by: Aluminium on March 25, 2020, 10:09:38 AM
March 8-24.

2019 (https://forum.arctic-sea-ice.net/index.php/topic,2591.msg192825.html#msg192825).
Title: Re: The 2020 melting season
Post by: Sourabh on March 25, 2020, 12:18:29 PM
Does anyone know what impacts the lower air pollution (and cleaner sky in some parts of the world due to the on-going pandemic) might have on the ice? I am vaguely aware of hearing that airplanes form clouds that reflect sun light, which might be totally incorrect. But, if it is, then is it possible that we might seem record melt this year due to increased incoming radiations, keeping everything equal?

Apologies if my linking of both crises seems insensitive.
Title: Re: The 2020 melting season
Post by: Tom_Mazanec on March 25, 2020, 01:10:43 PM
Sourabh:
That has been discussed on other threads.
The consensus seems to be that the pandemic will exacerbate AGW and sea ice loss.
Title: Re: The 2020 melting season
Post by: kassy on March 25, 2020, 06:18:03 PM
Basically it is an ongoing experiment.

We will see.

But who knows how much all the factors weight against each other.

One thing not to forget is how much we contribute with our regular day to day stufff.

The widget on the ASIF blog is at 2,853,860,000 hiroshima bombs of heat since 1998. That is our usual business.

On the long term the ice being thinner will make it more mobile with peripheral areas opening up early allowing ever more drift.

It´s going to be hard to tease apart but lets see what the ice does.

Title: Re: The 2020 melting season
Post by: HapHazard on March 25, 2020, 08:06:34 PM
Baffin, Barents, Bering and (B)Okhotsk.

You forgot St. Blawrence.
Title: Re: The 2020 melting season
Post by: forkyfork on March 26, 2020, 12:40:34 AM
no letup in the fram export pattern on today's EPS. click to animate
Title: Re: The 2020 melting season
Post by: Glen Koehler on March 26, 2020, 02:54:38 AM
RE revisiting the upthread discussion on crummy looking ice in the Beaufort Sea:
That said, this drop highlights how the change in the quality of the ice is changing how the melt season progresses.
It is less about extent and area.
It is more about age, thickness and volume.
Most of the ice that's appeared this year in the Barents and Bering above and beyond what wasn't there the last few years is barely coherent, and doesn't have any ability to resist weather.
It will likely vanish like morning mist on a hot spring day.
... I also don't like all the yellow I'm seeing in this graphic.  That concentration is a lot lower than I'd like.

Re Bremen image and Beaufort.
It didn't look so bad on the 19th compared to 22nd.
I wonder is it sensor related or is that Beaufort thinning real ? 

 ArcticMelt2  ( https://forum.arctic-sea-ice.net/index.php/topic,2888.msg236503.html#msg236503 (https://forum.arctic-sea-ice.net/index.php/topic,2888.msg236503.html#msg236503) )
pointed out this study from August 2018 that seems relevant to the recent Beaufort observations:

Warming of the interior Arctic Ocean linked to sea ice losses at the basin margins
BY MARY-LOUISE TIMMERMANS, JOHN TOOLE, RICHARD KRISHFIELD
SCIENCE ADVANCES29 AUG 2018 : EAAT6773
https://advances.sciencemag.org/content/4/8/eaat6773 (https://advances.sciencemag.org/content/4/8/eaat6773)
https://advances.sciencemag.org/content/advances/4/8/eaat6773.full.pdf (https://advances.sciencemag.org/content/advances/4/8/eaat6773.full.pdf)
"Abstract
Arctic Ocean measurements reveal a near doubling of ocean heat content relative to the freezing temperature in the Beaufort Gyre halocline over the past three decades (1987–2017). This warming is linked to anomalous solar heating of surface waters in the northern Chukchi Sea, a main entryway for halocline waters to join the interior Beaufort Gyre. Summer solar heat absorption by the surface waters has increased fivefold over the same time period, chiefly because of reduced sea ice coverage. It is shown that the solar heating, considered together with subduction rates of surface water in this region, is sufficient to account for the observed halocline warming. Heat absorption at the basin margins and its subsequent accumulation in the ocean interior, therefore, have consequences for Beaufort Gyre sea ice beyond the summer season."

Some images copied from the Timmermans et al study:
(https://forum.arctic-sea-ice.net/proxy.php?request=http%3A%2F%2F204.197.0.54%2FMEmodel%2FBeaufortHeat.png&hash=40044fbeda9cb3d0657e85c597aa6b78)


A press story about the Timmermans et al 2018 study is at
https://phys.org/news/2018-08-archived-deep-arctic-interior.html (https://phys.org/news/2018-08-archived-deep-arctic-interior.html)

"The upper ocean in the Canadian Basin has seen a two-fold increase in heat content over the past 30 years, the researchers said. They traced the source to waters hundreds of miles to the south, where reduced sea ice has left the surface ocean more exposed to summer solar warming. In turn, Arctic winds are driving the warmer water north, but below the surface waters.

"This means the effects of sea-ice loss are not limited to the ice-free regions themselves, but also lead to increased heat accumulation in the interior of the Arctic Ocean that can have climate effects well beyond the summer season," Timmermans said. "Presently this heat is trapped below the surface layer. Should it be mixed up to the surface, there is enough heat to entirely melt the sea-ice pack that covers this region for most of the year."  "

Related press article at
https://www.livescience.com/arctic-ice-refuge-vanishing.html (https://www.livescience.com/arctic-ice-refuge-vanishing.html)

Finally this one (abstract only unless you have paywall access)
Spatiotemporal Variability of Sea Ice in the Arctic's Last Ice Area
https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2019GL083722 (https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2019GL083722)



Title: Re: The 2020 melting season
Post by: blumenkraft on March 26, 2020, 08:03:54 AM
abstract only unless you have paywall access

https://sci-hub.tw/https://doi.org/10.1029/2019GL083722#
Title: Re: The 2020 melting season
Post by: uniquorn on March 26, 2020, 11:03:20 AM
There is evidence that the heat is there in the Beaufort from whoi itp114 (https://www.whoi.edu/page.do?pid=165196) but at 30m depth, with little visible mixing, it is unlikely to have a large impact at the moment. sep20-mar26
Salinity is steadily rising at 5m depth but that could be down to brine release from ice formation. 
click for full resolution. Day numbers at bottom of charts
Title: Re: The 2020 melting season
Post by: Niall Dollard on March 26, 2020, 11:50:11 AM
Yes the Timmerman's et al study is a very important one.

But also yes Uniquorn, I am struggling to see any other evidence that would back up the thinning in the central Beaufort.

I've perused much of the data available on the ESRL website but can't see anything to confirm concentration down to 75 % (as indicated by Bremen).
 
https://www.esrl.noaa.gov/psd/forecasts/seaice/
Title: Re: The 2020 melting season
Post by: uniquorn on March 26, 2020, 12:44:59 PM
I suspect that it is due to heavy cloud cover and/or other atmospheric conditions at this time of year. There was a similar discussion last year (and some before that)
Here is uni-hamburg mar31 2019 for comparison. It disappeared a few days later.
It is also visible on Aluminium's 2019 link above.
Title: Re: The 2020 melting season
Post by: gandul on March 26, 2020, 01:24:54 PM
Polar vortex seems to be weakening (per Judah Cohen twitter feed), and the low-mid troposphere is showing changes in parallel, like this ridge reaching well into the Pacific side for a few days.
(Sunday forecast ECMWF).
Title: Re: The 2020 melting season
Post by: blumenkraft on March 26, 2020, 01:42:48 PM
I suspect that it is due to heavy cloud cover and/or other atmospheric conditions at this time of year.

Since it's moving around, i agree!
Title: Re: The 2020 melting season
Post by: jai mitchell on March 26, 2020, 05:53:45 PM
Zack Labe reports unprecedented early rates of sea ice declines.

https://twitter.com/ZLabe/status/1243211454121005057

Title: Re: The 2020 melting season
Post by: kassy on March 26, 2020, 09:00:05 PM
Look also at the Big Beast - the 3.22 million km2 of the Central Arctic Sea. Still totally inviolate and concentration (Area divided by Extent) at almost at 100% of absolute maximum.

It´s in a good spot but that is all surface. If you look at the multiyear ice disappearing/ the arms getting thinner that has consequences. The ice drifts more and who knows how much more energy comes into the system.

It all froze up a bit this freezing season but all gains are already gone.

There were some hints on the Mosaic thread about floes slamming together and making thick ice also below the water. This acts as anchors but i bet i happens much less then it used to do just because there is so much less thick ice slamming into each other. 
Title: Re: The 2020 melting season
Post by: johnm33 on March 27, 2020, 10:31:02 AM
I wonder if the accelerated losses pushing 2020 into second place are to do with tidal forcings around the near equinox new moon. I've looked for years for convincing evidence of tidal action on flows through Fram and Nares and although it's still ambiguous this is the first year there's any real sign of effects/influence on sea ice movement.
Looking at the thick ice west of CAA it always seems it should be more free flowing through the channels, once they clear, but the action around Mosaic indicates that the ice acts in synchrony with it's 'captive' still water directly beneath it which may add a couple of oom to it's inertial mass and thus it's the water beneath the shear line that moves through the channels, i think. If the gyre fires up and begins to cycle the thick ice through to Chukchi we may see only thin ice in this area, so substantially less mass to get moving and potentially much greater losses from the freshwater lens.
Title: Re: The 2020 melting season
Post by: Tom_Mazanec on March 27, 2020, 11:02:26 AM
I wonder how long till I start reading “lowest area ever” in this thread like I was reading last year.
Title: Re: The 2020 melting season
Post by: uniquorn on March 27, 2020, 11:37:51 AM
Following up on amsr2 ice concentration in the Beaufort. The present conditions perhaps alter or amplify surface reflections that are not normally visible since the sensor is picking up features that move with the ice, probably ridges. (Temporarily providing us with SIC ridges as opposed to SIC leads (https://twitter.com/seaice_de/status/1221805753050320896)) Heavy contrast has been applied to the right hand image.

The second animation shows a more persistent low concentration area in the Laptev. We will find out soon enough if that is real or also an artifact of 'conditions'

unihamburg-amsr2uhh, beaufort, mar14-26 and ess/laptev, mar10-26
Title: Re: The 2020 melting season
Post by: Jim Hunt on March 27, 2020, 02:17:39 PM
There are a fair few leads sprinkled across the Beaufort Sea, but no widespread areas of reduced concentration. To my eyes at least:

https://go.nasa.gov/2vX84M6
Title: Re: The 2020 melting season
Post by: blumenkraft on March 27, 2020, 02:41:10 PM
Perhaps those cracks vent enough humidity to saturate the air to confuse the sensors?
Title: Re: The 2020 melting season
Post by: tybeedave on March 27, 2020, 03:57:54 PM
not to beat a dead horse, but
 
Export in a southerly direction through Fram is still huge. and the melt in the eastern GS is still beyond huge (see image), although the warm water influx from the Pacific seems to have slowed somewhat.

Although it's too early to quantify, this past solid month of export and melt may have crippled the arctic sea ice's prospect of surviving as a whole through summer

This export and melt so early in the season portend to the scary prospect of open water at the pole this Sept. imho

(https://forum.arctic-sea-ice.net/proxy.php?request=http%3A%2F%2F&hash=35d7d5d7526c9897dfb55501e320295a)
Title: Re: The 2020 melting season
Post by: Glen Koehler on March 27, 2020, 04:02:26 PM
RE Fram export
Wipneus chart from March 19
https://forum.arctic-sea-ice.net/index.php/topic,119.msg254996.html#msg254996 (https://forum.arctic-sea-ice.net/index.php/topic,119.msg254996.html#msg254996)
Title: Re: The 2020 melting season
Post by: Glen Koehler on March 28, 2020, 12:33:30 AM
GFS shows March ending with a blast of above normal temperature for the Chukchi, Beaufort, and much of the CAB
http://204.197.0.54/MEmodel/CR-GFS-Arctic2020-03-31.png (http://204.197.0.54/MEmodel/CR-GFS-Arctic2020-03-31.png)
Title: Re: The 2020 melting season
Post by: Freegrass on March 28, 2020, 01:17:30 AM
Weird situation in the Bering strait in the coming days, where the wind will blow north and south, most likely splitting the ice.

https://earth.nullschool.net/#2020/03/29/0000Z/wind/surface/level/orthographic=-45.02,91.24,2006
Title: Re: The 2020 melting season
Post by: jdallen on March 28, 2020, 04:04:36 AM
Weird situation in the Bering strait in the coming days, where the wind will blow north and south, most likely splitting the ice.

https://earth.nullschool.net/#2020/03/29/0000Z/wind/surface/level/orthographic=-45.02,91.24,2006

Strong man tearing apart the phone book.

Heh.  Everyone still get that reference?
Title: Re: The 2020 melting season
Post by: Rodius on March 28, 2020, 04:25:50 AM
Weird situation in the Bering strait in the coming days, where the wind will blow north and south, most likely splitting the ice.

https://earth.nullschool.net/#2020/03/29/0000Z/wind/surface/level/orthographic=-45.02,91.24,2006

Strong man tearing apart the phone book.

Heh.  Everyone still get that reference?

I asked my 11 year old if he knew what a phone book was. He said, "Yeah, those books with phone numbers that were used in the olden days."
Title: Re: The 2020 melting season
Post by: tybeedave on March 28, 2020, 01:01:02 PM
 After reviewing Worldview images since feb 20, '20, and while taking into account that these are daily images of local noon, I only saw only ONE day of the last 36 in which a southerly or easterly wind was not blowing exported ice into individual bergs into oblivion in the relatively warm waters of the eastern GS.
 The splitting of this ice into individual bergs greatly accelerates the melt process by depriving these ice chunks of brotherly chill and exposing all sides to relatively warm (>0C) water.

 The massive and accelerated melting of Fram-exported ice will have a debilitating effect on the central ice mass's ability to fight against the enemy known as the heat of summer, especially with this event having happened so early in the season. 

 Frozen rivers often have an event when the ice breaks up and starts to flow downriver.  The term escapes me, but were it not for the CAA's refrigerating effect, the import thru the Bering and export thru Fram straits made it seem that the entire arctic ice mass was ready to break up and just flow (I would hope that it stabilizes, but it may not if S/E wind directions continue over the GS). 
With respect to all the great providers (there are so many) on this blog, the overall view I have concerning our ice is both exciting and horrifying. 

It's kinda ironic that it is taking an acute virus scare for many people (nobody here) to stop and understand the great peril that Global Warming and a BOE represents.  Because they are now stuck at home and only now have the time to recognize what happens when you're not nice to Mother Nature, it seems people have become so bored that they are reading.  A great asset (reading) to those that don't want to repeat regretable, preventable histories of failures in the protection of said mother.

Anyone can make a gif for their own viewing of the GS (or anywhere else) over the last FORTY days on Worldview and be as horrified and yet excited as me.

I'm not exaggerating when I say that everywhere that I go in real life, as well as online, I try to enlighten others concerning the future through recalling the history of some wonder of nature that no longer exists.  I am not shy.  I am driven by a vision of my grandchildren's future in which a frozen arctic is only a memory, but i am not a doomsayer.  I believe that thru education, our ability to progress as a species is enhanced and I am passionate about this subject.

I know I'm preaching to the choir here.  Forgive me for my rant, Neven, and i hope this post wasn't OT or otherwise out of place.  It was an effort at self-help by an individual with too good a memory.  It was beneficial :)

td
gtgdgr
Title: Re: The 2020 melting season
Post by: blumenkraft on March 28, 2020, 01:29:53 PM
Welcome, Dave. :)

Just one thing: Icebergs is ice originating from calving glaciers. The ice coming down the Fram is mostly not icebergs. They are ice floes (frozen seawater).

Ice floes are several centimeters or meters thick. Icebergs, on the other hand, can be several hundred meters thick.
Title: Re: The 2020 melting season
Post by: binntho on March 28, 2020, 01:50:23 PM
I'm a bit mystified by the GS mentioned in a few posts above. Is it meant to be short for the Gulf Stream? Doesn't really make sense to me, e.g. "the relatively arm waters of the eastern GS" - where is that?
Title: Re: The 2020 melting season
Post by: kassy on March 28, 2020, 01:58:05 PM
I would opt for Greenland Sea.

Basically when using abbreviations that are not general like AMOC type the full version once before shortening it is clearer that way.
Title: Re: The 2020 melting season
Post by: binntho on March 28, 2020, 02:13:05 PM
Sounds reasonable if we are talking Fram Export - but why the "relatively warm waters of the eastern GS"?  Where you have floating ice in the Greenland Sea, the surface is at the melting point (-1.8C) and going outside of the ice covered areas, the temps are not really any higher, and nowhere above 0C.

However, looking at the ice edge all the way down from Svalbard to well south of Iceland, rapid melt is obviously ongoing, judginng by the aptly mis-named "froth".

Not that there is anything unusual about this situation, Fram export is not in any way different this winter from other winters, judging by Wipneus' charts. (https://forum.arctic-sea-ice.net/index.php/topic,119.msg254996.html#msg254996)
Title: Re: The 2020 melting season
Post by: Freegrass on March 28, 2020, 03:30:53 PM
Weird situation in the Bering strait in the coming days, where the wind will blow north and south, most likely splitting the ice.

https://earth.nullschool.net/#2020/03/29/0000Z/wind/surface/level/orthographic=-45.02,91.24,2006

Strong man tearing apart the phone book.

Heh.  Everyone still get that reference?

I asked my 11 year old if he knew what a phone book was. He said, "Yeah, those books with phone numbers that were used in the olden days."
That was too funny...  ;D Reminds of that video of a small child that was wondering how you could text with an old school rotary dial phone.

Welcome to ASIF tybeedave! Good post! It's going to be a crazy melting season this year with the sun beating down unabated on the planet. Exciting indeed, but scary as hell!
Title: Re: The 2020 melting season
Post by: gerontocrat on March 28, 2020, 03:43:09 PM
Not that there is anything unusual about this situation, Fram export is not in any way different this winter from other winters, judging by Wipneus' charts. (https://forum.arctic-sea-ice.net/index.php/topic,119.msg254996.html#msg254996)

Looking at the Wipneus graph (attached below) seems to show below average or average Fram export until mid-Jan. After that looks like more times above than below average.

This is maybe confirmed by the Greenland Sea sea ice area graph (attached), which shows sea ice increasing from below the 2010's average in January to well above that 10 year average by mid-March. Seems to me that an educated guess says at least some of that is due to increased Fram export.

ps: From purely occasional random looks at Nullschool wind direction and strength, perhaps some of that ice exported from the CAB was shoved into the Barents?



Title: Re: The 2020 melting season
Post by: Freegrass on March 28, 2020, 09:03:48 PM
Look at what's about to happen in Greenland.  ??? The melting season seems to come early this year...

https://earth.nullschool.net/#2020/03/29/1800Z/wind/isobaric/1000hPa/overlay=temp/orthographic=-27.87,70.00,1746/loc=-45.554,65.374

And all this is happening because of the jetstream that curled in onto itself and became a giant high pressure system that's creating a high pressure "storm" on the surface.

Has anyone seen anything like this before? Is this the future of the jetstream? Giant vortices circulating the planet and wreaking havoc?

https://earth.nullschool.net/#2020/03/29/1800Z/wind/isobaric/250hPa/orthographic=-23.29,64.74,1003
Title: Re: The 2020 melting season
Post by: uniquorn on March 28, 2020, 09:09:30 PM
Looking at the Wipneus graph
This is maybe confirmed by the Greenland Sea sea ice area graph<>
Volume is similar, area is higher = thickness is lower.
Title: Re: The 2020 melting season
Post by: peterlvmeng on March 29, 2020, 03:24:22 AM
I remember that 2012 there is a relatively large ice area in North Atlantic Ocean in spring. I wonder the large sea ice area will amplify the AMOC effect although it has been weaken for recent decades. We all know low arctic sea ice area will weaken the North Atlantic current. The large sea ice area in Atlantic Ocean will accelerate the ocean current exchange because more salinity and cold temperature. The momentum of ocean current will be helpful in melting the summer arctic sea ice. Together with  the high pressure and temperature in mid latitude will help to form cyclones in North Atlantic arctic region. All these will push more ice from CAB to Barrent Sea and Greenland Sea which will amplify the AMOC current.

All in All, all these effect will accelerate the ocean heat exchange with arctic sea ice than ever before.
Title: Re: The 2020 melting season
Post by: grixm on March 29, 2020, 09:00:10 AM
March 28th, 2020:
     13,559,443 km2, a drop of -19,954 km2.
     2020 is now the lowest on record.   :P

Greatest comeback since the 2005 UEFA Champions League Final
Title: Re: The 2020 melting season
Post by: tybeedave on March 29, 2020, 09:38:27 AM
good morning all !

blumenkraft, ty for the heads up.  You're right they are not icebergs, i should have stuck with 'chunks of ice' or ice floes.  Sometimes I forget that these posts should be necessarily specific.

GS is the Greenland Sea, I thought I had seen the abbrev. in the glossary.  I shall try to not make up designations in the future.

binntho, I didn't mean the water directly adjacent to the floes but just a little way out past the melt. The attached image from nullschool illustrates the 'warmth' directly south of Prins Karl's Isl. which only increases as one goes in a southerly direction.

kassy...noted

"Fram export is not in any way different this winter from other winters, judging by Wipneus' charts."  Concerning Wipneus' charts.  The Info that he provides is of immense value, however, a visual comparison between this year and last shows quite a difference.  Image attached.(https://forum.arctic-sea-ice.net/proxy.php?request=http%3A%2F%2F&hash=35d7d5d7526c9897dfb55501e320295a)

Thank you, Freegrass, and yes, your nick says it all.  why pay for something that nature provides freely :)

peterlvmeng, i agree, this is related to the point that I'm trying to make.  The amount of heat exchange through the ice melt that has been occurring in the Greenland Sea is huge.  There is a very large amount of heat also in the Barents Sea.  The potential for an extreme melt of the CAB by the heat transferred north by Atlantic currents and through the Bering St is real. One might note that these currents of relatively warm water continue along the coast past Novaya Zemlya where a melt is also currently occurring.

As a side note,  I can remember when Novaya Zemlya was surrounded by fast ice year-round.



td
Title: Re: The 2020 melting season
Post by: tybeedave on March 29, 2020, 10:01:48 AM
Freegrass, all I can say about your 2nd nullschool link, in your recent post, of the anticyclone is

WOW !!!

tks

td
Title: Re: The 2020 melting season
Post by: blumenkraft on March 29, 2020, 10:25:48 AM
We are mentioned in Paul Beckwith' latest video. :)

He talks about the shifting of the polar vortex towards Greenland in this video.

https://www.youtube.com/watch?v=okFp2nwKotg
Title: Re: The 2020 melting season
Post by: blumenkraft on March 29, 2020, 10:42:35 AM
March 28th, 2020:
     13,559,443 km2, a drop of -19,954 km2.
     2020 is now the lowest on record.   :P

Greatest comeback since the 2005 UEFA Champions League Final

Welp, that escalated quickly.   :-[
Title: Re: The 2020 melting season
Post by: tybeedave on March 29, 2020, 10:45:40 AM
blumenkraft,

at the risk of appearing as mushy as much of the ice in the cryosphere,

you are indeed a 'flower power'

you do a really great job on so many threads

thank you

do you sleep?   j/k

td
Title: Re: The 2020 melting season
Post by: Niall Dollard on March 29, 2020, 10:55:23 AM
March 28th, 2020:
     13,559,443 km2, a drop of -19,954 km2.
     2020 is now the lowest on record.   :P

Greatest comeback since the 2005 UEFA Champions League Final

But not as great as the 1999 UEFA Champions League final. You would need a BOE for that !  :)
Title: Re: The 2020 melting season
Post by: blumenkraft on March 29, 2020, 10:57:43 AM
thank you

do you sleep?


Aww, thanks, Dave! :)

Yes, according to my profile stats, i do sleep. ;)
Title: Re: The 2020 melting season
Post by: VeliAlbertKallio on March 29, 2020, 12:38:48 PM
It looks increasingly possible that the Laxton Sea materialises this summer as forecasted by the late University College London (UCL) researcher in his seminal forecast on the Arctic Ocean sea ice trend. Variability remains great, so the blue ocean event is perhaps, hopefully, still just a remote possibility.

March 28th, 2020:
     13,559,443 km2, a drop of -19,954 km2.
     2020 is now the lowest on record.   :P

Greatest comeback since the 2005 UEFA Champions League Final

But not as great as the 1999 UEFA Champions League final. You would need a BOE for that !  :)
Title: Re: The 2020 melting season
Post by: blumenkraft on March 29, 2020, 12:48:17 PM
Bering Strait. Crackification north of Alaska is going fast.

Title: Re: The 2020 melting season
Post by: oren on March 29, 2020, 01:20:23 PM
td, thanks for your thoughts on Fram export and the GS situation.
ASCAT animations posted by uniquorn from time to time show an increase in Fram export in the last few weeks. A big chunk of the CAB shifted southwards. I fail to recall what thread had such an animation recently, but I recommend to seek it and watch it.

Edit: well here it is from upthread

An overview of sea ice movement as seen by ascat (https://manati.star.nesdis.noaa.gov/ascat_images/ice_image/msfa-NHe-a-2020083.sir.gif), jan1-mar23
The amsr2 low concentration area in/around the Beaufort correlates quite well with the darker area on ascat but may also be related to the recent heavy cloud cover.
Title: Re: The 2020 melting season
Post by: Freegrass on March 29, 2020, 02:12:12 PM
The sea ice is so thin around ellesmere island, and look at that volume graph...  ???


Title: Re: The 2020 melting season
Post by: Frivolousz21 on March 29, 2020, 02:22:52 PM
That is a hell of a dipole anomaly models are showing it doesn't last very long though but man that is monstrous begins at June or mid to late May while things could really get cooking early this year
Title: Re: The 2020 melting season
Post by: blumenkraft on March 29, 2020, 02:58:22 PM
Welcome back, Frivolousz!

Hey, what's your take on missing data due to fewer airplanes and, subsequential, how reliable the weather models are at the moment?
Title: Re: The 2020 melting season
Post by: binntho on March 29, 2020, 03:00:36 PM
We all know low arctic sea ice area will weaken the North Atlantic current.

I didn't. Do you have any supportive evidence for this claim? Or any of the below:

Quote
The large sea ice area in Atlantic Ocean will accelerate the ocean current exchange because more salinity and cold temperature. The momentum of ocean current will be helpful in melting the summer arctic sea ice. Together with  the high pressure and temperature in mid latitude will help to form cyclones in North Atlantic arctic region. All these will push more ice from CAB to Barrent Sea and Greenland Sea which will amplify the AMOC current.
Title: Re: The 2020 melting season
Post by: binntho on March 29, 2020, 03:05:11 PM

"Fram export is not in any way different this winter from other winters, judging by Wipneus' charts."  Concerning Wipneus' charts.  The Info that he provides is of immense value, however, a visual comparison between this year and last shows quite a difference.

No it doesn't.

There is slghtly more extent and more area and the last couple of months have seen slightly more voluminous export, but nothing to shout about and nothing out of the ordinary and it wil not effect this coming melting season in any way.
Title: Re: The 2020 melting season
Post by: blumenkraft on March 29, 2020, 03:13:34 PM
last couple of months have seen slightly more voluminous export

From what i see in the Sunday SAR movies, i would second that. But this is only my impression, i can't deliver any data on that.
Title: Re: The 2020 melting season
Post by: johnm33 on March 29, 2020, 05:59:57 PM
It looks to me like the whole top 75m[?] of the ocean is moving in concert very slowly toward/out of Fram, at least in that quarter of the Arctic. There's water being drawn in from the Pacific whether it's related or not, and the ice there seems to be outpacing the water for now. So a huge amount of turbulence coming, and then it looks like there could be a big storm in a few [3-5]days not a promising start.
Title: Re: The 2020 melting season
Post by: blumenkraft on March 29, 2020, 06:47:41 PM
Here we go with the Sunday movies.  ;D

Fram export via SAR is missing the 24th (never came in) and today (flight path sucks so i didn't include it).
Title: Re: The 2020 melting season
Post by: blumenkraft on March 29, 2020, 06:49:08 PM
Ice drift map.

CAA still hold'n strong!
Title: Re: The 2020 melting season
Post by: blumenkraft on March 29, 2020, 06:50:51 PM
And last but not least, the 7-day hindsight mean temperature anomalies.
Title: Re: The 2020 melting season
Post by: uniquorn on March 29, 2020, 08:42:49 PM
nothing out of the ordinary
One thing that is different, or that I haven't seen before, is the large leads that have developed since feb15 making their way around north greenland so early in the season. With >80km/h winds (https://earth.nullschool.net/#2020/04/01/2100Z/wind/surface/level/overlay=temp/orthographic=-57.41,88.78,1309/loc=-23.606,83.575) forecast on apr1 we are likely to see them open up more.
Kaleschke SIC leads, oct1-mar29
Title: Re: The 2020 melting season
Post by: blumenkraft on March 29, 2020, 08:50:47 PM
Amazing! Thanks so much, Uniquorn. :)
Title: Re: The 2020 melting season
Post by: oren on March 30, 2020, 02:53:22 AM
Thank you as usual uniquorn.
To anyone who thinks nothing unusual has happened re Fram export, I recommend to play the animation and not focus on Fram itself, where a trickle from the northeast can be seen all winter, but on some random ice shape below the pole. One can see how the ice moves in a random walk fashion for several months, mostly moving nowhere with a slight southern drift. But then starting around mid-February a big sweep comes along, and the ice from the pole moves all the way to the Fram finish line, a distance of more than 1000 km IIRC. This is significant volume gone, and an important piece of the Arctic's defenses against the melting season.
Title: Re: The 2020 melting season
Post by: Glen Koehler on March 30, 2020, 02:56:42 PM
One thing that is different, or that I haven't seen before, is the large leads that have developed since feb15 making their way around north greenland so early in the season. With >80km/h winds (https://earth.nullschool.net/#2020/04/01/2100Z/wind/surface/level/overlay=temp/orthographic=-57.41,88.78,1309/loc=-23.606,83.575) forecast on apr1 we are likely to see them open up more.
Kaleschke SIC leads, oct1-mar29
Anybody else with historical perspective on how unusual it is for (what I think should thick) ice just north of Greenland to be fractured this early in the season?  Seems very strange and significant to me, but I don't have the years of observation to compare it to.
Title: Re: The 2020 melting season
Post by: nanning on March 30, 2020, 03:12:03 PM
Thanks uniquorn. Great work.
Title: Re: The 2020 melting season
Post by: uniquorn on March 30, 2020, 06:04:18 PM
historical perspective
It's difficult to compress a long time series into a small enough file size so this is 6.5MB for ascat fram export 2010-2020. The present episode doesn't look like the worst thing that has happened (yet).
I can remove this after 47hrs if it causes problems to low bandwidth users.

Also large, but not auto downloaded is worldview, terra modis, closest non cloudy day to mar29, 2000-2020. Medium contrast has been applied to highlight leads.
Some years look worse, 2010 looks bad in a different way. click to run

uni-hamburg amsr2uhh, caa and nth greenland, 2012-2018 can be found here (https://forum.arctic-sea-ice.net/index.php/topic,2839.msg235294.html#msg235294)
Title: Re: The 2020 melting season
Post by: tybeedave on March 30, 2020, 10:23:38 PM
ty uniquorn,

your movie may be the best i have even seen on asif
i'm alarmed even more than i was.
great work, i have low bandwidth but i think it would be a travesty for you to remove it. it is the highlight of the whole forum....now i'm going to watch it again...and again...
i wish i could post it in every forum i could find, even FB :)

td
Title: Re: The 2020 melting season
Post by: Niall Dollard on March 30, 2020, 11:36:04 PM
Thanks Uniquorn.

That was one big lead in March 2010. 15 km wide just above Ellesmere.

Title: Re: The 2020 melting season
Post by: Glen Koehler on March 31, 2020, 12:07:28 AM
Nice work, thanks uniquorn!  I think that gets the Academy Award for technical achievement in Fram Strait documentation.  The different views complement each other and the time series overview provides superb historical context.

    After repeated watchings, my takeaway impression is that the ice in the north of Greenland - Fram Strait regions is very dynamic.  I should have known that from the analysis shown in:
"Spatiotemporal Variability of Sea Ice in the Arctic's Last Ice Area"
https://sci-hub.tw/https://doi.org/10.1029/2019GL083722# (link courtesy of blumenkraft) but the visual impression from 10 years of images is more convincing at a gut level.  While the interannual variability gets visually swamped by the within-year melt season - freezing season patterns, the overall impression is how it's always changing and that spring 2020 is not obviously different than in earlier years.

     That said, indicators of volume and thickness say that not only is the long term ASI decline continuing, but 2020 is heading into the melt season in wounded condition.   As others have noted, the supposedly strong refreeze in Jan - Feb 2020 looks like an easily reversed flash in the pan, i.e. weak thin ice that temporarily adds to the Extent value but is not indicative of improvement to the long term health of the ASI.

    I didn't see direct relevance of the Nullschool windspeed at 250 hPa image posted by Freegrass (important for steering weather patterns at jet stream height, but not directly influential like surface winds that interact with ice).  But that got me to check today's Nullschool and Climate Reanalyzer surface winds and temperature anomalies.  Those show what seems to be a significantly large and strong wind field from the Bering Strait bringing in unusually warm air almost reaching the North Pole.  And another large area of surface wind that is bringing warm air from the south directly toward north Greenland.  As or the "Polar Vortex", we need to define our terms and choose the right pressure level to distinguish between the stratospheric and tropospheric polar vortexes. 

     While not dramatically stronger than normal, the recently robust Fram Strait drift and export measures are another setup.  The occurrence of leads north of Greenland does not seem unprecedented in the noisy record over the previous 10 years in uniquorn's animations, but the overall ASI situation seems sensitive to rapid losses if strong melt season conditions arrive.  2020 could be a wild ride.

BTW - nice explanation of leads vs cracks vs polynas at https://en.wikipedia.org/wiki/Lead_(sea_ice)
Title: Re: The 2020 melting season
Post by: uniquorn on March 31, 2020, 12:27:24 PM
ascat day60-89 comparison (or closest available day), 2010-2020. First year ice distinguishable by location and darkness. click to run
Maybe Niall will measure the movement :)
Title: Re: The 2020 melting season
Post by: blumenkraft on March 31, 2020, 12:52:26 PM
Thanks so much, Uniquorn.

So,  (almost) any year has a clockwise movement, do i see that correctly?

Is this the Coriolis force we see here?
Title: Re: The 2020 melting season
Post by: Freegrass on March 31, 2020, 01:33:48 PM
Fram export will get another boost this week.
Title: Re: The 2020 melting season
Post by: PragmaticAntithesis on March 31, 2020, 11:24:58 PM
Fram export will get another boost this week.

As if it needed one!
Title: Re: The 2020 melting season
Post by: johnm33 on March 31, 2020, 11:43:36 PM
Thanks uniquorn, I guess we'll all see what we want, for me what's most striking is the apparent direct movement from Bering to Fram in 3 of the last 4 years with this year clearly the most pronounced. We're half-way between peak tides so i'm wondering if the full moon tides around the 8th accelerate or punctuate it, all down to atmospherics for now.
Looking at the ice face-ing N.A. and the fancy hair, maybe this should be in pareidolia too?
Title: Re: The 2020 melting season
Post by: interstitial on April 01, 2020, 12:23:26 AM
Has anyone else noticed this odd protrusion between northern greenland and Svalbard island. It has been there for a while and it looks like it should just break off but it hasn't. Or is it normal?
Title: Re: The 2020 melting season
Post by: Freegrass on April 01, 2020, 02:56:38 AM
Is this the beaufort gyre that is starting up?
Title: Re: The 2020 melting season
Post by: binntho on April 01, 2020, 05:00:28 AM
We're half-way between peak tides  ...

Tides have no effect on Fram export. Tidal effects (other than a smooth up-and-down motion) are strictly limited to the narrow coastal strip, perhaps 10 meters max into open ocean. Swells and surges can happen in enclosed waters, but only on a scale of a few hundreds of meters.

If you think differently, you can start your own thread and explain your reasoning there.
Title: Re: The 2020 melting season
Post by: jdallen on April 01, 2020, 07:42:23 AM
Has anyone else noticed this odd protrusion between northern greenland and Svalbard island. It has been there for a while and it looks like it should just break off but it hasn't. Or is it normal?
I expect normal.  In past years, there would typically be a (much larger) bench of thicker, land-fast ice just to the south of that location, and it frequently was much larger.

Over the last 10-15 years, it generally starts breaking up around this time.  How it looks now isn't unusual at all.
Title: Re: The 2020 melting season
Post by: grixm on April 01, 2020, 08:19:28 AM
Has anyone else noticed this odd protrusion between northern greenland and Svalbard island. It has been there for a while and it looks like it should just break off but it hasn't. Or is it normal?

The ice is anchored to the seabed below. In 2012 there was a similar long and relatively thin protrusion, but even as it started to shatter in July, it still held on for a while even as the part connecting it to the mainland broke off: https://worldview.earthdata.nasa.gov/?v=269947.6895835763,-1001118.4511475239,925307.6895835763,-656030.4511475239&p=arctic&t=2012-07-20-T10%3A00%3A00Z

You can see there is an area of shallow water around there too: (https://www.gebco.net/news_and_media/images/ne_greenland.jpg)
Title: Re: The 2020 melting season
Post by: Glen Koehler on April 01, 2020, 08:21:50 AM
moved to When Will Arctic Be Ice Free thread
Title: Re: The 2020 melting season
Post by: blumenkraft on April 01, 2020, 09:03:52 AM
Tidal effects (other than a smooth up-and-down motion) are strictly limited to the narrow coastal strip

You were wrong about this the last X-times you stated it and you are wrong now again. You can't think ice movement without also taking tides into account.

Therefore, the tide movements are absolutely not off-topic in this thread.
Title: Re: The 2020 melting season
Post by: binntho on April 01, 2020, 09:06:18 AM
Good points Glen. My take on the linear vs. exponential (or other curved) declines is that the underlying decline is linear to the extent that it follows the near-as-makes-no-difference linear increase in global temperatures (so far).

On the other hand, I would expect acceleration at some point. So linear now, accelerate later. This is purely intuitive so I won't make any big claims!
Title: Re: The 2020 melting season
Post by: blumenkraft on April 01, 2020, 09:06:44 AM
I expect normal.  In past years, there would typically be a (much larger) bench of thicker, land-fast ice just to the south of that location, and it frequently was much larger.

Or bottom-fast even?
Title: Re: The 2020 melting season
Post by: binntho on April 01, 2020, 09:08:59 AM
Tidal effects (other than a smooth up-and-down motion) are strictly limited to the narrow coastal strip

You were wrong about this the last X-times you stated it and you are wrong now again. You can't think ice movement without also taking tides into account.

Therefore, the tide movements are absolutely not off-topic in this thread.

So tell me how the tides move the ice! What research has been done on this pheomenon, and what are the particulars of the kinetic transfer from tidal movement to ice movement.

I have never seen anybody give any explanation for their strange fixation on tidal effects, so I will continue to claim that they do not exist.
Title: Re: The 2020 melting season
Post by: binntho on April 01, 2020, 09:13:22 AM
The constant flow of low-pressure areas up the North Atlantic cause the exact same up-and-down movement as the tidal effect, due to changes in pressure. And changes in gravity (i.e. tidal effects) are of course de facto changes in pressure.

Nobody has ever claimed that this constant up and down movement due to low pressures moving over the surface can ever have any effect on the lateral movement of ocean waters (or surface ice), except for the purely coastal effect (the same as the tides).

So how does the tidal effect manage this?
Title: Re: The 2020 melting season
Post by: blumenkraft on April 01, 2020, 09:27:49 AM
Last time we talked about this i gave you multiple GIFs illustrating and proving my point. You all dismissed them without counterargument. So no, i will not do it again.
Title: Re: The 2020 melting season
Post by: binntho on April 01, 2020, 09:51:58 AM
Last time we talked about this i gave you multiple GIFs illustrating and proving my point. You all dismissed them without counterargument. So no, i will not do it again.

I remember those gifs. There was no point in responding to them because they either showed the coastal effect. Which I keep saying is real, but of no importance since it only reaches a very short distance away from the coast. Or they were not really conclusive, more a question of wanting to see something.

Besides, the coastal effect is mostly back-and-forth movement caused by the up-and-down movement in shallow waters, and should therefore have an extremely limited (if any) effect on the movement of ice and water in the open ocean.

The open ocean, thousands of kilometers from side to side, is what we are talking about here. And the lateral movement of ice (and water) in the open ocean does not fluctuate with the tides.

HOWEVER!!!!!

Long-term movements of ocean currents ARE effected by the tidal pull of the moon. So the effect is not non-existent in the open ocean, but it is NOT a fluctuating effect. In other words, no research i've found indicates that changes in tidal movement on a daily or monthly basis has any discernible effect.

The existence of tides has a constant effect, not a fluctuating effect, changes in the tides on a daily or monthly  basis does not effect the large scale state of the ice in the Arctic Ocean.
Title: Re: The 2020 melting season
Post by: blumenkraft on April 01, 2020, 10:03:13 AM
Binntho, does the word "bathymetry" ring a bell?

I have news for you: Bathymetry is all over the place.
Title: Re: The 2020 melting season
Post by: Hopen Times on April 01, 2020, 10:16:55 AM
Binntho, how do you define shallow waters and how far from the coast do you think you can observe the coastal effect?
Title: Re: The 2020 melting season
Post by: johnm33 on April 01, 2020, 10:24:58 AM
'Tides' I'm busy but I'll make my case later on unsorted.
Title: Re: The 2020 melting season
Post by: Freegrass on April 01, 2020, 10:37:28 AM
I have never seen anybody give any explanation for their strange fixation on tidal effects, so I will continue to claim that they do not exist.
I used to go fishing with my dad in the north sea, with a zodiac. And I remember it like it was yesterday, that very first time we threw anker. It was amazing! The current was so powerful that it was like we were still driving the boat.

So tides do move a lot of water. Especially in between islands, because that's where the tide is held up, creating a bulge of water that needs to squeeze through those islands.

I'm also a diver. I dived the kilima drift. One of the fastest drift dives in the world. I really have no idea why anyone would ever say that tides don't move water laterally. It's the most natural thing of all...
Title: Re: The 2020 melting season
Post by: oren on April 01, 2020, 10:57:26 AM
A gentle request to posters:
Last time the tide subject was discussed in here, there were endless examples and posts all arguing against binntho's point. Which did nothing to convince him.
I suggest that binntho or some other good soul open a thread for the effect of tides on currents and sea ice, and let all the endless re-posts be done there.
Otherwise, I suggest to ignore the claim that tides do nothing. It will surely derail this thread.
Title: Re: The 2020 melting season
Post by: gerontocrat on April 01, 2020, 11:26:57 AM
There is also a thread When will the Arctic Go Ice Free? where I thought discussions about the BOE were to be held.

https://forum.arctic-sea-ice.net/index.php/topic,2348.msg253549.html#msg253549

Surely the 2020 melting season thread is about 2020? And 2020 will not see a BOE anyway - with ideal melting conditions maybe 1.5 million km2 below trend@ 2.5 million km2.
Title: Re: The 2020 melting season
Post by: Aluminium on April 01, 2020, 12:12:07 PM
March 22-31.

2019 (https://forum.arctic-sea-ice.net/index.php/topic,2591.msg193241.html#msg193241).
Title: Re: The 2020 melting season
Post by: Jim Hunt on April 01, 2020, 12:23:03 PM
At the risk of drifting off topic, there is currently an unprecedented "ozone hole" above the North Pole:

http://GreatWhiteCon.info/2020/03/facts-about-the-arctic-in-april-2020/#Apr-01

Quote
Researchers measure ozone levels by releasing weather balloons from observing stations around the Arctic (including the Polarstern icebreaker, which is frozen in sea ice for a year-long expedition). By late March, these balloons measured a 90% drop in ozone at an altitude of 18 kilometres, which is right in the heart of the ozone layer. Where the balloons would normally measure around 3.5 parts per million of ozone, they recorded only around 0.3 parts per million.
Title: Re: The 2020 melting season
Post by: Tom_Mazanec on April 01, 2020, 01:00:53 PM
A gentle request to posters:
Last time the tide subject was discussed in here, there were endless examples and posts all arguing against binntho's point. Which did nothing to convince him.
I suggest that binntho or some other good soul open a thread for the effect of tides on currents and sea ice, and let all the endless re-posts be done there.
Otherwise, I suggest to ignore the claim that tides do nothing. It will surely derail this thread.
Here's the thread:
https://forum.arctic-sea-ice.net/index.php/topic,3030.0.html
Title: Re: The 2020 melting season
Post by: blumenkraft on April 01, 2020, 01:17:11 PM
I started to download ozone pictures as an addition for my weekly Sunday movies premiering next Sunday.

Jim, why do you think it's off-topic? Should i use another thread to post them?
Title: Re: The 2020 melting season
Post by: Glen Koehler on April 01, 2020, 03:23:01 PM
Deleted Confidence interval posts.  Will move to "When will Arctic Go Ice Free" later.
Title: Re: The 2020 melting season
Post by: gerontocrat on April 01, 2020, 03:54:49 PM
Deleted Confidence interval posts.  Will move to "When will Arctic Go Ice Free" later.
Thanks, Glen.

Every so often I go to the "When will Arctic Go Ice Free" to see new ideas and methodologies on the BOE question. When one posts BOE things like yours on this thread it often quickly gets lost in the "noise" of numerous posts about the current season.

I, for one, hope you repost this stuff onto the BOE thread ASAP. They were great. I am sort of gradually building up a new set of data on area, extent and volume, also splitting the 14 seas into the High Arctic Seas (i.e. the Arctic Ocean proper as defined by Nico Sun in his AWP models)) and the Peripherals.

Maybe this could be plugged into your equations?

Cheers,

Gero

 
Title: Re: The 2020 melting season
Post by: tybeedave on April 01, 2020, 04:15:17 PM
hiyas,

this may be OT and my apologies if it so judged.  But, as a  response regarding some FYI messages that I have received, for clarification, is the statement 'a north wind blows in a southerly direction through the Fram' correct? Likewise, doesn't a south wind blow in a northerly direction ?

I am a native English speaker, but i could be wrong.

td
Title: Re: The 2020 melting season
Post by: philopek on April 01, 2020, 06:35:40 PM
hiyas,

this may be OT and my apologies if it so judged.  But, as a  response regarding some FYI messages that I have received, for clarification, is the statement 'a north wind blows in a southerly direction through the Fram' correct? Likewise, doesn't a south wind blow in a northerly direction ?

I am a native English speaker, but i could be wrong.

td

google is your friend (in such cases)  :)

https://www.thefreedictionary.com/southerlies

https://www.google.com/search?q=southerlies&oq=southerlies&aqs=chrome..69i57j0l7.7865j1j3&sourceid=chrome&ie=UTF-8
Title: Re: The 2020 melting season
Post by: Jim Hunt on April 01, 2020, 09:09:33 PM
Jim, why do you think it's off-topic?

Personally I think the ozone hole is sufficiently on topic in here, although perhaps actually more suited to the "freezing season" thread if that were still active?

Certainly more on topic here than certain other recent posts!
Title: Re: The 2020 melting season
Post by: PragmaticAntithesis on April 01, 2020, 09:29:44 PM
hiyas,

this may be OT and my apologies if it so judged.  But, as a  response regarding some FYI messages that I have received, for clarification, is the statement 'a north wind blows in a southerly direction through the Fram' correct? Likewise, doesn't a south wind blow in a northerly direction ?

I am a native English speaker, but i could be wrong.

td

A North Wind is a wind blowing from the North. Of course, anything going from North is going to the opposite direction of North, AKA South.
Title: Re: The 2020 melting season
Post by: tybeedave on April 01, 2020, 10:22:52 PM
hi yall,
 
I made the transition from lurker to new ice primarily because I felt it necessary to bring focus upon the, imho, extreme melt event occurring in the Greenland Sea.
Now, after watching oren's outstanding 10 yr movie of the Fram area (I dled it and i download little that I come across outside urls)many times, I noted that there appeared to be an export into the Barents Sea of a much more extreme volume of 'old' ice than any that occurred in 2010-11, '13, '14' and '17 (the years in which there was significant export visible).

The thing is, ALL ice that is exported melts in the summer, and there is a significantly above normal % of the CAB being exported right this minute! and this event has been going for 45 days and we have six (6) more months of melt!

I recognize that the wind and other conditions may change, but since mid Feb, sea ice has been forced out of the CAB into the Barents and Greenland seas at rates that I have never before seen in my limited experience.  It is true that one's eyes sometimes deceive them, but in this case, I think not.

I urge all of you to notice this truly extreme melt event that has unfolded and maybe use its example to convince others that the time to talk about the BOE occurring has passed.  It's now time to mitigate the short-sighted views of some of our political leaders and really, ourselves.  Now is the time to act even if all you can do is lead by example when we choosing future leaders.

I'm not much of an activist, but when I see a problem, I address it, even if I don't possess the reviewed evidence to submit a formal paper.  I never claimed to be a scientist.  I'm just an average man that knows that we, the members of ASIF and its lurkers, must act, at the best of our abilities, to spread the word that the continued assault on nature really can only have a bad ending for humanity.

I've (i hope) done my good deed for the day by illuminating a cause of concern and offering a (hackneyed) way to help alleviate it....  Should anyone, especially neven, disagree with me, I am always open to new data and correction if necessary. 

I will entertain all ideas, suggestions, and criticism toward my efforts in making a better future for my living grandchildren and the greatgrandchildren that will be arriving in just a few years.

peace

my apologies if I'm 'preaching to the choir'

td


Title: Re: The 2020 melting season
Post by: kassy on April 01, 2020, 11:37:50 PM
The whole setup did not look too well (see post 3 or 4 or so for the picture).

I wish i had a better feel for the numbers but i don´t. There are fram export numbers in the Wipneus Piomas data thread so we will see eventually.

Don´t know how long you have been lurking but years vary. Some get off to an amazing start and then nothing happens in summer and years start slow and then turn amazing (see ASIF blog 2012 climate dominoes posts f.e.).

In general we can conclude that the ice is not in great shape from the picture mentioned above, snippits from Mosaic and the way the impressive extent numbers got wiped out quickly while all the time you could see more action in area then usual during melt season (but this could just be my impression only really started paying detailed attention last few years).

I really think that more mobile ice and drift of whatever is left could become interesting at some point but it very much depends on how things continue. What seas will open early? Will there be unusual storms (mixing up deep warm water etc).

I bet it is going to be an interesting year.
Title: Re: The 2020 melting season
Post by: kassy on April 02, 2020, 01:38:39 AM
#Gerontocrat

I have wondered if you have a file with all the daily changes in Area ever (since current format) and do these show more movement over the years? (same for extent but it should be less?).

Title: Re: The 2020 melting season
Post by: Juan C. García on April 02, 2020, 01:41:49 AM
Now, after watching oren's outstanding 10 yr movie of the Fram area (I dled it and i download little that I come across outside urls)many times, I noted that there appeared to be an export into the Barents Sea of a much more extreme volume of 'old' ice than any that occurred in 2010-11, '13, '14' and '17 (the years in which there was significant export visible).
Sometimes the images can be misleading. We can see that more ice is being export, at the same time that the ice volume export is not that high. Why? Because we are seeing more area moving, but with thinner ice than other years.

P.S. Maybe I saw another movie, what I saw is Uniquorn movie...
Title: Re: The 2020 melting season
Post by: Freegrass on April 02, 2020, 01:54:30 AM
Now, after watching oren's outstanding 10 yr movie of the Fram area (I dled it and i download little that I come across outside urls)many times, I noted that there appeared to be an export into the Barents Sea of a much more extreme volume of 'old' ice than any that occurred in 2010-11, '13, '14' and '17 (the years in which there was significant export visible).
Sometimes the images can be misleading. We can see that more ice is being export, at the same time that the ice volume export is not that high. Why? Because we are seeing more area moving, but with thinner ice than other years.
True, but the little that is left of the MYI is going down the drain together with that thin ice.
Title: Re: The 2020 melting season
Post by: Juan C. García on April 02, 2020, 02:00:48 AM
Sometimes the images can be misleading. We can see that more ice is being export, at the same time that the ice volume export is not that high. Why? Because we are seeing more area moving, but with thinner ice than other years.
True, but the little that is left of the MYI is going down the drain together with that thin ice.
Yes. I think that the first time that we will see a BOE, the ice exported will play an important role. I'm just questioning what is happening now. I am not expecting a big ice export number in March.
Title: Re: The 2020 melting season
Post by: kassy on April 02, 2020, 02:11:28 AM
But now redo that as total vol vs exported.

It has been ages since i watched ice die live but i used to live near a park and watching it in the last day was interesting.

Older ice which runs into more old ice can make really big bumps either up or down. The down bumps are like fins slowing down the movement of the ice (usually). They can be impressively big (there is an example on the mosaic thread but i cannot recall the actual post or page). 

We can only imagine how they would have looked last decade or this decade because no one thought it was worthwhile to fund a proper science project looking at the arctic (relatively cheap compared to whatever we spent on armies and banks).

There is this interplay between Vol Ext and Are. Now area going down with volume basically means a more mobile ice pack.

The data will do what it used to do until some underlying fundamentals change.

Title: Re: The 2020 melting season
Post by: oren on April 02, 2020, 02:18:04 AM
Now, after watching oren's outstanding 10 yr movie of the Fram area (I dled it and i download little that I come across outside urls)many times, I noted that there appeared to be an export into the Barents Sea of a much more extreme volume of 'old' ice than any that occurred in 2010-11, '13, '14' and '17 (the years in which there was significant export visible).
I agree, ice from the direction of the Pole moved farther this year than in other years. However, this was indeed uniquorn's animation, I am just a promoter of these movies.
Title: Re: The 2020 melting season
Post by: binntho on April 02, 2020, 07:27:25 AM
Bashing peoples' pet theories is never going to make one popular, and having a low silliness tolerance threshold can be a curse.

My current tidal rant started when somebody rambled on about visible changes in Fram export being somehow linked to the tides. Total rubbish in my mind, as are similar claims that have been made previously.

Gifs and anectdotes are not evidence in this case. There is absolutely no science to back up the Fram export/tide effect, there are is no data, there are no chains of causality that can be brought to bear to support such claims.

Somebody mentioned the bathymetry thing above. That was another frequently banded-about pet theory that many people referred to but did not really seem to understand. At least, nobody was able to explain what they were talking about when pushed. Eventually a few of the more knowledgable of the members managed to piece together the scientific evidence and the data (and I did a lot of research myself) and the bathymetry thing was resolved - I accepted that it was a real thing in very many areas of the Arctic, and I hope that some others managed to understand why that is the case. Was forcing people to look at the science behind their claims such a bad idea? Perhaps if this was the forum of a religious cult, yes, but not in a forum for scientific discourse.

The same goes for the tidal debacle. My own research into the matter has not turned up the least iota of support for a large scale and fluctuating tidal effect on ice movement in the open ocean. Nobody on this forum has been able to show any supporting evidence. The ongoing Mosaic expedition would be a prime example - have they ever mentioned tidal effects on the movement of ice around their vessel? Not that I've seen.

Pointing out your previous failure to provide evidence, and me still going on about it, does not make me more likely to accept your claims. I'll move my own rants over to the newly created tidal group (https://forum.arctic-sea-ice.net/index.php/topic,3030.msg257361.html#new), and I look forward to the company of anybody who would want to join me there in the sport of exasperating and irritating each other.
Title: Re: The 2020 melting season
Post by: blumenkraft on April 02, 2020, 07:32:03 AM
binntho, there is a thread for that now. You might ignore the science there.
Title: Re: The 2020 melting season
Post by: binntho on April 02, 2020, 07:43:06 AM
binntho, there is a thread for that now. You might ignore the science there.
You might try reading what people post!
Title: Re: The 2020 melting season
Post by: oren on April 02, 2020, 08:56:02 AM
Thank you binntho.
Title: Re: The 2020 melting season
Post by: gandul on April 02, 2020, 01:57:27 PM
Cracks are starting to show along Beaufort coast, may develop further near McKenzie Delta given the forecast. (Yesterday's Worldview Terra visible)
Title: Re: The 2020 melting season
Post by: tybeedave on April 03, 2020, 01:01:43 AM
I hope my contributions help someone.

  Pls, note the activity in the Bering st.  There is another pulse of warm water entering the CAB. I haven't learned how to make a gif, but one of the last week would illustrate my point.

I call it as i see it.  Others may see it differently or question the validity of what I see and communicate.  Oh well...

I do know for a fact that the whole CAB is a relatively thin layer of water in which seiche activity and its attendant force transfer is real.  And if one jams water through the Bering as is happening now, it has to drain.  Unfortunately, it carries lots of sea ice with it as it is forced through the Fram. I see more than normal though I recognize that specifics cannot be easily derived from the movie and it is somewhat subjective for me to speculate.

The charts and graphs available here are great and many people put large efforts into their accuracy.  But, my eyes are not deceiving me.  There are very large forces involved in moving that much water.

If I might ask, when a wave enters through the Bering Strait, how long does the energy of that wave take to reach the Nares?  3,000 km, a few days? attached is an image of such a wave from 2 days ago.

https://worldview.earthdata.nasa.gov/?v=-2691064.456174864,1073468.9659112212,-1572856.456174864,1597756.9659112212&p=arctic&t=2020-03-31-T22%3A32%3A16Z (https://worldview.earthdata.nasa.gov/?v=-2691064.456174864,1073468.9659112212,-1572856.456174864,1597756.9659112212&p=arctic&t=2020-03-31-T22%3A32%3A16Z)



 as the melt event continues in the Greenland sea

(https://forum.arctic-sea-ice.net/proxy.php?request=http%3A%2F%2F&hash=35d7d5d7526c9897dfb55501e320295a)

td

Title: Re: The 2020 melting season
Post by: pearscot on April 03, 2020, 06:28:24 AM
Hi, it's been a bit since I've been here (been just sad af about covid 19).

ANYWAYS, there are a number of items I'm really interesting in seeing this season, or if they remain a carryover from last year. The first, and most prominent, being the massive crack above Greenland (which actually amazed me last year). Second, I will be interested to see if more upwelling from the Bering Sea is exacerbated by the late refreeze. Lastly, I wonder how robust the export in the Fram will be.

Not to mention, to my eye, I think this will either be a neutral, or very, very slight la nina year. And will reduced pollution have an affect on albieto?

I'm going to try to follow this as much as possible amidst everything else going on in the sad state of the world
Title: Re: The 2020 melting season
Post by: interstitial on April 03, 2020, 07:34:41 AM
<snip>
Not to mention, to my eye, I think this will either be a neutral, or very, very slight la nina year.  <snip>

Oni index
https://origin.cpc.ncep.noaa.gov/products/analysis_monitoring/ensostuff/ONI_v5.php
Year   DJF   JFM   FMA   MAM   AMJ   MJJ   JJA   JAS   ASO   SON   OND   NDJ
2019   0.8   0.8   0.8   0.7   0.6   0.5   0.3   0.1   0.1   0.3   0.5   0.5
2020   0.5                                 
The working NOA definition for el nino is +0.5 or greater for five consecutive three month averages so it might develop a very slight el nino but the earliest it could be classified la nina is after August.
Title: Re: The 2020 melting season
Post by: grixm on April 03, 2020, 11:19:22 AM
Extreme Fram export continues: (https://forum.arctic-sea-ice.net/proxy.php?request=http%3A%2F%2Fosisaf.met.no%2Fquicklooks%2Fprod%2Fice%2F2020%2F03%2Fice_drift_nh_polstere-625_multi-oi_202003311200-202004021200_combo.png&hash=3f6e557f32b358ea6020d2238ec1e11d)
Title: Re: The 2020 melting season
Post by: Glen Koehler on April 03, 2020, 12:40:57 PM
     ONI3.4 forecast (sea surface temperature in equatorial region of Pacific Ocean used to estimate ENSO El Nino / La Nina cycle) are updated monthly on 3rd Thursday at
 https://iri.columbia.edu/our-expertise/climate/forecasts/enso/current/?enso_tab=enso-sst_table
 (https://iri.columbia.edu/our-expertise/climate/forecasts/enso/current/?enso_tab=enso-sst_table)
Title: Re: The 2020 melting season
Post by: Niall Dollard on April 03, 2020, 01:46:48 PM
Around this time of year I usually take a screenshot of the ESRL Ice thickness assessment. Here are the years 2018, 2019 compared with forecast thickness 7th April 2020. (not on exact same dates but within +/- 1 week).

It does n't augur well for the coming summer.

The legend is the same for each chart with max pink colour indicating thickness of 1.6m or more. For resistence against the Arctic melt season you would be hoping for pink colour spread across the whole Arctic by now. But we are far from that.

Four areas in particular have thicknesses a lot lower than previous years:

1. Kara

Very thin and expect it will melt out quickly this year. Maybe not as crucial as other areas as it usually melts out every year anyway. Having said that an early melt would not be good for preserving ice in the main basin.

2. Polarstern

(dubbed this area - after where the Polarstern research vessel started out last Autumn). This area is near the heart of the basin and is thin. As much of the good ice heads south into the Fram, outlook for this area is not good at all. Could we see the ice edge retreat back to the pole this year with most of the ice only on the American side and maybe a typical arm heading out towards the ESS ?

3. Western Beaufort/Northern Chukchi

Thinner than usual. Legacy of late freeze ups, Pacific infiltration. This century these areas melt out every year but like the Kara an early melt out would make for an aggressive melt attack on the Basin.

4. Laptev

A lot thinner than usual. Legacy of the record mild winter over Russia. Expect an early appearance of the Laptev polynya and maybe eventually melting back to the pole ?

Title: Re: The 2020 melting season
Post by: Ktb on April 03, 2020, 04:08:58 PM
Wind in excess of 50 kph pushing ice out the Fram. Greater than 55 kph north of Greenland moving ice in that direction as well.
Title: Re: The 2020 melting season
Post by: tybeedave on April 03, 2020, 08:43:22 PM
.

philopek,
ty so much for the dictionary link.  You had a positive effect on my model of reality.  I recognized something new for me.  That is an increased understanding of the importance of context.  The word, 'southerly,' can be the source of confusion, so I will use 'southward' in the future.  I actually enjoy revising my model to better reflect the realities of nature.  Intuitively, I had assumed my knowledge, as a trained linguist, of the word was correct.  My intuition was wrong.

grixm,
 I have been wondering about the remaining fast ice in NE Greenland.  Thanks so much for providing the data that really shows why it persists, ie, it is attached, probably, to the bottom.  This agrees with my intuition.

I was going to list everyone that has impacted my thinking by their posts on this blog in the last few days, but the list is so long, and in some respects, i am so lazy, i will just say thanks to yall and keep the data and analysis coming!  It is appreciated.

While I'm dishing out compliments, let me thank binntho in particular.  I admire his ability to take a stand for veracity as well as his avoidance of direct personal attacks.  The calming and beneficial aspect of bringing other's heads down has a value.  Suggestions that a view may be skewed are beneficial because it creates closer scrutiny of the problem at hand enabling a better overall understanding.  So, binntho, TY for bringing my head down.  May I return the favor.


peace

td


Title: Re: The 2020 melting season
Post by: gerontocrat on April 03, 2020, 09:13:20 PM
hiyas,

this may be OT and my apologies if it so judged.  But, as a  response regarding some FYI messages that I have received, for clarification, is the statement 'a north wind blows in a southerly direction through the Fram' correct? Likewise, doesn't a south wind blow in a northerly direction ?

I am a native English speaker, but i could be wrong.

td

A North Wind is a wind blowing from the North. Of course, anything going from North is going to the opposite direction of North, AKA South.
The convention is the wind direction is named for where the wind is coming from. But in the Arctic I am often confused.

When the wind (as it sometimes does) starts in Siberia, heads across the Arctic Ocean and reaches the North American or Greenland shores, it starts as a South wind, & after crossing the pole becomes a North Wind. Even worse is when the wind and ice shifts from the Pacific side to the Atlantic side very close to 0 / 180 longitude. One moment its on the Russian side heading West, and in the blink of an eye crosses that longitude and is heading East. Polarstern did that.
___________________________________________________
ps: I have posted now & then that there is no correlation between JAXA sea ice extent at maximum and the subsequent minimum. I thought I would have a closer look to see if a link between a high or low maximum and a following high or low minimum exists.

So here are two graphs of deviations in March & September from the linear trend. The first is a column graph by year, the second an XY graph.

EDIT - Graphs not done well. New versions posted.
Title: Re: The 2020 melting season
Post by: oren on April 04, 2020, 01:29:16 AM
Dave, I wish you had posted your long binntho-related missive in the new Tides thread. Here it will only generate more endless discussion, and to no avail.
Title: Re: The 2020 melting season
Post by: El Cid on April 04, 2020, 07:46:05 AM
Around this time of year I usually take a screenshot of the ESRL Ice thickness assessment. Here are the years 2018, 2019 compared with forecast thickness 7th April 2020.
It does n't augur well for the coming summer.
....

Very nice pictures Niall! Confirms what I see on the Bremen maps: unusual weakness from Barents to Kara/Laptev and also on the Alaskan side. It will be very hard to dodge that bullet this year
Title: Re: The 2020 melting season
Post by: HapHazard on April 04, 2020, 08:03:57 AM
Indeed. Thanks for that post, N.D.
Title: Re: The 2020 melting season
Post by: charles_oil on April 04, 2020, 11:39:52 AM

Yes - enjoyed ND post - thanks - once I worked out orientation ;)  - very worrying and worth watching - is this possible as a monthly / bi-monthly analysis (pretty please... ) ?
Title: Re: The 2020 melting season
Post by: Niall Dollard on April 04, 2020, 12:05:52 PM
Thanks for those comments Charles, HapHazard and El Cid.

I don't mind doing more when I can but I'm limited in that I havent taken that many screenshots from other years (unfortuantely).

Next one I have is May 1st 2018. So I could do a comparison this year with that one.

Just looking back at last year and the chart for 13th April 19 still showed a lot of pink - and we all know what happened after that.

This is what makes me all the more concerned this year, that we are only barely starting the melt season and condition is poor in many areas, especially the Russian side.

It will be interesting to see the next PIOMAS volume update to end of March. I imagine there won't be much of an increase on the mid-March and we are very near the volume max for the year,   
Title: Re: The 2020 melting season
Post by: Paul on April 04, 2020, 03:06:18 PM
Thanks for those comments Charles, HapHazard and El Cid.

I don't mind doing more when I can but I'm limited in that I havent taken that many screenshots from other years (unfortuantely).

Next one I have is May 1st 2018. So I could do a comparison this year with that one.

Just looking back at last year and the chart for 13th April 19 still showed a lot of pink - and we all know what happened after that.

This is what makes me all the more concerned this year, that we are only barely starting the melt season and condition is poor in many areas, especially the Russian side.

It will be interesting to see the next PIOMAS volume update to end of March. I imagine there won't be much of an increase on the mid-March and we are very near the volume max for the year,

I do think the ESS and Laptev seas need watching this year, there is not much fast ice this year(because of the positive AO) so all ready we got less protection to the main ice pack itself all ready. Of course if the winds keep blowing off the Russian landmass then we may see early open water appearing like we did in the ESS in 2017 where it was unprecedented just how much open water there was so early in the melt season.

I Also think last year we will have a stall in the volume charts because of export and extent loss, hopefully it won't be a sign of things to come!
Title: Re: The 2020 melting season
Post by: tybeedave on April 04, 2020, 09:17:14 PM
oren, better yet, i deleted most of it, my bad, subject closed

td
Title: Re: The 2020 melting season
Post by: Ktb on April 05, 2020, 12:20:15 PM
Nullschool says there is water in the Beaufort, north of Yukon/Northwest Territories.
Title: Re: The 2020 melting season
Post by: Freegrass on April 05, 2020, 12:53:20 PM
1.7°C reported in the Laptev sea for next week. Long way out, but things are really starting to heat up in Russia in the coming days.

In Belgium, we're already doing summer temperatures for the coming week.  ???

https://earth.nullschool.net/#2020/04/09/0900Z/wind/surface/level/overlay=temp/orthographic=-42.14,101.34,3000/loc=115.536,73.901
Title: Re: The 2020 melting season
Post by: Aluminium on April 05, 2020, 02:26:36 PM
The Ob River wakes up.

https://www.youtube.com/watch?v=pElfjbMM5IQ (https://www.youtube.com/watch?v=pElfjbMM5IQ)
Title: Re: The 2020 melting season
Post by: Davidsf on April 05, 2020, 02:43:41 PM
That's impressive video footage of the Ob River, Aluminum. Thank you for sharing it. Do you know if this is an early melt onset?
Title: Re: The 2020 melting season
Post by: Aluminium on April 05, 2020, 03:06:59 PM
Mid April is more usual for this. Ice is thin and easy to break after warm winter.
Title: Re: The 2020 melting season
Post by: Sublime_Rime on April 05, 2020, 05:23:20 PM
Nullschool says there is water in the Beaufort, north of Yukon/Northwest Territories.

Yep, worldview yesterday and today confirms an early opening in the Beaufort.
Title: Re: The 2020 melting season
Post by: gerontocrat on April 05, 2020, 05:57:30 PM
Bee in My Bonnet - Small rant follows.

As the melting season progresses there will be much talk and comparisons with 2012.  Wrong year!

If you look at the attached first graph you will see that 2016 was the year that mattered most (apart from a brief spurt in 2012 at the end of the melt season).

If you look at the second graph of 365 day trailing averages, you will see that the 2016 continuous long melt and slow freeze resulted (in March 2017) in the record low average. i.e. Looking at the entire year, 2016 had the lowest amount of sea ice by far - an average of 400,000 km2 for every day of the year less than the 2012 record low (in Jan 2013).

2012 was a shooting star - phut, & it was gone. 2016 was the steady burn that really matters.

The same result shows for extent & volume - see graphs 3 & 4.
Title: Re: The 2020 melting season
Post by: blumenkraft on April 05, 2020, 06:19:18 PM
The Sunday movies gave birth to a new type of movie.

The Ozone layer via Copernicus!

The scale is in Dobson Units (DU)
Quote
A dobson unit is the most basic measure used in ozone research.One Dobson Unit (DU) is defined to be 0.01 mm thickness at STP (standard temperature and pressure). Ozone layer thickness is expressed in terms of Dobson units, which measure what its physical thickness would be if compressed in the Earth's atmosphere. In those terms, it's very thin indeed. A normal range is 300 to 500 Dobson units, which translates to an eighth of an inch-basically two stacked pennies.
Title: Re: The 2020 melting season
Post by: blumenkraft on April 05, 2020, 06:20:38 PM
Ice drift map shows the CAA gave up its staticness this week.
Title: Re: The 2020 melting season
Post by: blumenkraft on April 05, 2020, 06:22:12 PM
7-day temperature anomalies. The Arctic runs hot! Canada still very cold.
Title: Re: The 2020 melting season
Post by: blumenkraft on April 05, 2020, 06:23:43 PM
Saturday to Saturday (because Sunday flight paths are bitchy recently) Fram export via SAR.
Title: Re: The 2020 melting season
Post by: Tom_Mazanec on April 05, 2020, 07:38:29 PM
Quote
2012 was a shooting star - phut, & it was gone. 2016 was the steady burn that really matters.
But there could be another shooting star in 202X. This will be at least as likely to be the first BOE as is a gradual drop down year by year.
Title: Re: The 2020 melting season
Post by: Stephan on April 05, 2020, 09:43:19 PM
Quote
2012 was a shooting star - phut, & it was gone. 2016 was the steady burn that really matters.
But there could be another shooting star in 202X. This will be at least as likely to be the first BOE as is a gradual drop down year by year.
There will be another (at least one) shooting star in 202X, including the first BOE year.
Title: Re: The 2020 melting season
Post by: Jim Hunt on April 06, 2020, 12:41:53 PM
Here's the latest update on near real time CryoSat-2/SMOS "measured" Arctic sea ice volume:

http://GreatWhiteCon.info/2020/03/facts-about-the-arctic-in-april-2020/#Apr-06

Quote
I’ve applied a crude correction to the still problematic NRT data so that it at least coincides with the reanalysed data on March 14th. Whilst we await the reanalysed numbers for the rest of March and early April it looks as though Arctic sea ice volume reached at least a temporary peak on March 20th 2020.
Title: Re: The 2020 melting season
Post by: grixm on April 06, 2020, 03:48:50 PM
The difference just one week makes in the Beaufort sea. Click to play
Title: Re: The 2020 melting season
Post by: blumenkraft on April 06, 2020, 06:06:34 PM
Comparison of 2020 vs. 2019
Title: Re: The 2020 melting season
Post by: tybeedave on April 07, 2020, 03:44:08 AM
really great and significant data flower man,

I'm happy to see the visual decrease in export.  i fear that the mass of old ice replaced by new ice, in the hopefully past 45 day export/wind event, is over.  it appears that even a moderately warm spring will cause widespread melt that will be more apparent in gerontocrat's and others' charts and graphs as the weeks pass maybe.

we may have just witnessed a blow to the CAB on par with the late storm of '12.  i hope not, but i fear so, but what i believe means nothing...how much do you think this event, that reached from the Atlantic to the Pacific, inclusive, had on the minimum?    .thoughts?

td
Title: Re: The 2020 melting season
Post by: Niall Dollard on April 07, 2020, 12:14:53 PM
Persistent east winds have caused open water to appear in the eastern Hudson Bay. This is early in the season for break up.

I presume if winds turn west or northwest again this would close in ?
Title: Re: The 2020 melting season
Post by: uniquorn on April 07, 2020, 01:22:18 PM
Wipneus amsr2-uhh regional (https://sites.google.com/site/arcticseaicegraphs/regional) extent(blue) and area(yellow), baffin/st.lawrence/hudson, mar5
Title: Re: The 2020 melting season
Post by: Shared Humanity on April 07, 2020, 02:48:08 PM
it appears that even a moderately warm spring will cause widespread melt that will be more apparent in gerontocrat's and others' charts and graphs as the weeks pass maybe.

With the economy worldwide nearly shutdown and ground and air travel a fraction of what it normally is, emissions are dropping dramatically and, along with this, the effects of global shading or dimming. I expect us to have the hottest summer on record in the NH.
Title: Re: The 2020 melting season
Post by: dnem on April 07, 2020, 03:41:20 PM
We had a crystalline clear day yesterday here in the US mid-Atlantic coastal region. Last night Venus shown as clear and bright as I can remember.
Title: Re: The 2020 melting season
Post by: be cause on April 07, 2020, 05:50:21 PM
A lot of Euro -American air traffic flies over Ireland . Normally there are several planes in the air over us at any one time . The most I have seen is 13 . Today , like most days lately there is 1 nearly every hour . As I keep pointing out to the anti-con trail lobby .. their prayers have been answered by CV19 .. b.c.
 
Title: Re: The 2020 melting season
Post by: charles_oil on April 07, 2020, 05:57:25 PM

Sorry - off-topic quick reply - see https://planefinder.net/ to see the relative plane density over Europe … vs USA where skies look pretty busy!

Title: Re: The 2020 melting season
Post by: PragmaticAntithesis on April 07, 2020, 06:07:58 PM
Methinks the US still isn't taking this seriously...

Anyway, back to ice discussion. I still think we're overestimating the effects of aerosol cooling on polar regions. Increasing the sun's power slightly won't do much where the sun is barely shining anyway, especially compared to the usual effects of heat trapping. That said, we may get a nasty melt season anyway due to the incredible amount of Fram export and thin ice in and around the Chukchi.
Title: Re: The 2020 melting season
Post by: IceConcerned on April 07, 2020, 06:45:31 PM
But even if we get this extra cooling only at mid latitude that extra heat so generated will have to go somewhere, I would expect some movement northwards that would bring this melting force to the Arctic
Title: Re: The 2020 melting season
Post by: PragmaticAntithesis on April 07, 2020, 09:23:38 PM
Is there any explanation why Baffin Sea Ice is so much thicker in average this year and 2019 in comparison with the 2000s or 2010s?

IIRC it's because the thin ice is removed. Let's say you have a set of 7 blocks of ice with thickness 0.3, 0.5, 0.7, 0.9, 1.0, 1.2, 3.1. The average thickness here is 1.1 arbitrary units. Then, you have a nasty melt that takes 1 unit of thickness away from all the blocks. Now you only have 2 blocks (0.2, 2.1) with an average thickness of 1.15, as the other 5 blocks are gone.
Title: Re: The 2020 melting season
Post by: LeftyLarry on April 07, 2020, 09:41:10 PM
Methinks the US still isn't taking this seriously

As a humanitarian gesture the U.S. decided to allow American citizens abroad to return home to be with family and receive medical care if and when needed.
Unfortunately, one of the political parties refuses to allow changes to the chain migration laws under which non- citizen family members can come into the country to be reunited with existing American citizens.
My understanding is that from China alone 40,000 have been “repatriated”  to the U.S. to be with their brothers, cousins, uncles, grandparents etc. since the pandemic began.
The migration continues, even with the virus in the background.
Add that to the movement of consumer goods, food and medical equipment being sent from places with low virus issues to States where help is needed quickly and yes, the planes are still flying, though many less.
Many parts of the States are already beginning to see a flattening of the curve in regards to new cases and yes, it’s being taken very seriously in the U.S.
Back to the ice!
Title: Re: The 2020 melting season
Post by: Freegrass on April 07, 2020, 10:29:48 PM
Comparison of 2020 vs. 2019
There was a lot of ice pushed into the barents sea this winter. That explains the larger extent there. But overall, that's actually a bad thing, because the barents will melt out anyway. The problem is that this is ice that's been taken from the CAP.

Am I getting that right?
Title: Re: The 2020 melting season
Post by: Paul on April 08, 2020, 12:55:21 AM
Persistent east winds have caused open water to appear in the eastern Hudson Bay. This is early in the season for break up.

I presume if winds turn west or northwest again this would close in ?

Winds have been very strong also hence the break up but usually open water starts appearing on the western half of Hudson Bay during Spring. So as you say, once the winds turn, the ice will return and fill those holes back in.

As for the poster mentioning about extensive ice in Barants then that will be right for the most part that some of the ice would of came from the CAB, the only positive I would have with this it could mean Atlantification may not be much of an issue during the melt season. It was similar in 2019 where ice managed to stay around all during the melt season until the very end in September which resulted in  the extent going down below 4 million on JAXA.
Title: Re: The 2020 melting season
Post by: Tom_Mazanec on April 08, 2020, 02:58:27 AM
We won’t likely have a BOE this year but what is the chance of us beating the 2012 record in 2020?
Title: Re: The 2020 melting season
Post by: Rodius on April 08, 2020, 03:04:11 AM
Is there any explanation why Baffin Sea Ice is so much thicker in average this year and 2019 in comparison with the 2000s or 2010s?

IIRC it's because the thin ice is removed. Let's say you have a set of 7 blocks of ice with thickness 0.3, 0.5, 0.7, 0.9, 1.0, 1.2, 3.1. The average thickness here is 1.1 arbitrary units. Then, you have a nasty melt that takes 1 unit of thickness away from all the blocks. Now you only have 2 blocks (0.2, 2.1) with an average thickness of 1.15, as the other 5 blocks are gone.

Good explanation.... I will be using this to explain to my denier brother fairly soon.... not that he will listen lol
Title: Re: The 2020 melting season
Post by: Wherestheice on April 08, 2020, 04:32:23 AM
We won’t likely have a BOE this year but what is the chance of us beating the 2012 record in 2020?

I feel like after every year that passes, the chances of us passing 2012 goes up quite a bit. 2020 could easily be the year
Title: Re: The 2020 melting season
Post by: jdallen on April 08, 2020, 09:12:35 AM
We won’t likely have a BOE this year but what is the chance of us beating the 2012 record in 2020?

*Every* year going forward is a dice roll to beat 2020.  They are slowly but steadily being stacked in favor of beating the record.  As a SWAG, any given year right now I think has about a 1 in 3 chance of blowing by it.  It should be 1 in 2 before we get to 2025, and I expect a BOE around or about 2030.
Title: Re: The 2020 melting season
Post by: Aluminium on April 08, 2020, 11:22:55 AM
March 29 - April 7.

2019 (https://forum.arctic-sea-ice.net/index.php/topic,2591.msg194320.html#msg194320).
Title: Re: The 2020 melting season
Post by: Tom_Mazanec on April 08, 2020, 11:46:16 AM
We won’t likely have a BOE this year but what is the chance of us beating the 2012 record in 2020?

*Every* year going forward is a dice roll to beat 2020.  They are slowly but steadily being stacked in favor of beating the record.  As a SWAG, any given year right now I think has about a 1 in 3 chance of blowing by it.  It should be 1 in 2 before we get to 2025, and I expect a BOE around or about 2030.
Paul Beckwith posted a video a couple days ago where he estimated BOE as 2023.
Title: Re: The 2020 melting season
Post by: Paul on April 08, 2020, 12:48:39 PM
We won’t likely have a BOE this year but what is the chance of us beating the 2012 record in 2020?

*Every* year going forward is a dice roll to beat 2020.  They are slowly but steadily being stacked in favor of beating the record.  As a SWAG, any given year right now I think has about a 1 in 3 chance of blowing by it.  It should be 1 in 2 before we get to 2025, and I expect a BOE around or about 2030.
Paul Beckwith posted a video a couple days ago where he estimated BOE as 2023.

Apparently he thought a BOE could of happened in 2013 after 2012 big melt, certainly did not happen that way, let's see if he's right on this prediction in a few years time!

As for whether this year can beat 2012 then it's a possibility especially if holes start appearing in the middle of the ice pack during June like it did in 2012 and 2016.

I got a feeling the East Siberian Sea ice may melt out quickly like it did in 2017 given how little fast ice there is and the ice does look rather broken up and diffused.
Title: Re: The 2020 melting season
Post by: Jim Hunt on April 08, 2020, 01:03:39 PM
Paul Beckwith posted a video a couple days ago where he estimated BOE as 2023.

However please note that:

Quote
People like Beckwith want to go crazy every melting season

https://forum.arctic-sea-ice.net/index.php/topic,92.msg7451.html#msg7451
Title: Re: The 2020 melting season
Post by: grixm on April 08, 2020, 03:50:55 PM
We're off to a strong start in terms of albedo warming potential.
Title: Re: The 2020 melting season
Post by: The Walrus on April 08, 2020, 04:51:48 PM
We won’t likely have a BOE this year but what is the chance of us beating the 2012 record in 2020?

*Every* year going forward is a dice roll to beat 2020.  They are slowly but steadily being stacked in favor of beating the record.  As a SWAG, any given year right now I think has about a 1 in 3 chance of blowing by it.  It should be 1 in 2 before we get to 2025, and I expect a BOE around or about 2030.
Paul Beckwith posted a video a couple days ago where he estimated BOE as 2023.

Apparently he thought a BOE could of happened in 2013 after 2012 big melt, certainly did not happen that way, let's see if he's right on this prediction in a few years time!

As for whether this year can beat 2012 then it's a possibility especially if holes start appearing in the middle of the ice pack during June like it did in 2012 and 2016.

I got a feeling the East Siberian Sea ice may melt out quickly like it did in 2017 given how little fast ice there is and the ice does look rather broken up and diffused.

I put Paul Beckwith in the same league as Peter Wadhams, Wieslaw Maslowski, and Jay Zwally.
Dana Nuccitelli discusses these types in SKS:

https://skepticalscience.com/alarmists-not-in-deniers-league.html
Title: Re: The 2020 melting season
Post by: Jim Hunt on April 08, 2020, 05:27:26 PM
I put Paul Beckwith in the same league as Peter Wadhams, Wieslaw Maslowski, and Jay Zwally.

I don't!

By way of example, I discuss Wieslaw Maslowski's work here:

http://GreatWhiteCon.info/tag/wieslaw-maslowski/

Quote
Would it surprise you to discover that David Rose has misrepresented the “new study” that Al Gore referred to in 2007 as well, by some strange coincidence at around this time last year? I refer you to our article on that topic from September 15th 2013, and reiterate for the benefit of those who seem unable to understand either English or Mathematics that a “projection” is not the same thing as a “prediction”, and that Professor Wieslaw Maslowski’s statement that “if this trend persists the Arctic Ocean will become ice-free by around 2013” is not at all the same thing as David Rose’s (mis)interpretation that “The Arctic will be ice-free in summer by 2013”.

Title: Re: The 2020 melting season
Post by: kassy on April 08, 2020, 10:39:29 PM
NSIDC Area Graphs.

Attached are the graphs for...
- Total Area
- the 7 High Arctic Seas Area,
- the 7 Peripheral Seas Area.
As one can see in the High Arctic melt has not started.

Also attached is Baffin Bay Sea Ice Area - now 2nd lowest in the satellite record, and currently the Poster Child for the 2020 melt season.

What is the significance of Baffin Bay for the larger picture?

I don´t think much so i am waiting for the other lines to change.
Title: Re: The 2020 melting season
Post by: Paul on April 08, 2020, 11:05:07 PM
The issues I have with Paul Beckwith is that in many of his Arctic videos, its just him going on different websites and highlighting text and reading it out on what other people have said, there does not seem to be much analysis from him or his opinions. The only thing he does come out with he thinks a BOE is imminent and when it occurs, a BOE will occur all year round after 10 years of the first BOE. I think part of his theory is plausible as sea ice will be much slower to grow and thinner as a result going into the next melt season but I be majorly shocked if winter sea ice extent reduces that quickly in time.

The other issue with him, in his videos from a few years ago, he delivered them in an enthusiastic type of way but now it's a slower and dull sounding tone which makes watching his videos a bit tedious unfortunately.
Title: Re: The 2020 melting season
Post by: gandul on April 08, 2020, 11:54:29 PM
Paul Beckwith is a great wishful thinker, and one of these years he’ll be right, and he’ll be the king of ‘I thusly informed you’ for a while. But I think other people like Neven here have a much much better idea of what is going on in the Arctic.
Title: Re: The 2020 melting season
Post by: kassy on April 09, 2020, 12:44:48 AM
He is clutter guy i think?

Basically his presentation is as messy as his videos look and he is catering for a certain audience (for revenue) which does not improve on his messaging.

Title: Re: The 2020 melting season
Post by: oren on April 09, 2020, 04:27:18 AM
NSIDC Area Graphs.

Attached are the graphs for...
- Total Area
- the 7 High Arctic Seas Area,
- the 7 Peripheral Seas Area.
As one can see in the High Arctic melt has not started.

Also attached is Baffin Bay Sea Ice Area - now 2nd lowest in the satellite record, and currently the Poster Child for the 2020 melt season.

What is the significance of Baffin Bay for the larger picture?

I don´t think much so i am waiting for the other lines to change.
In general, the peripheral seas don't matter much, especially those that are remote (Hudson, Okhotsk, St. L) or downstream prevailing currents out of the Arctic (Greenland Sea, Baffin Bay, partially Barents). However it's all a connected system and early disappearance of sea ice can have a cumulative albedo effect on NH weather. Besides, an early breakup and clearance in northern Baffin Bay, as shown in Aluminium's gif, can potentially lead to early damage to the Nares arch, as well as contribute to CAA breakup.
Title: Re: The 2020 melting season
Post by: Jim Hunt on April 09, 2020, 08:21:05 AM
Paul Beckwith is a great wishful thinker.

I'm a wishful thinker too!

Could we possibly take the "alarmist"/"denialist" debate over to one of the Blue Ocean Event (https://forum.arctic-sea-ice.net/index.php/topic,2800.msg244868.html#msg244868) threads, and get back to the 2020 melting season in here?

For the record I agree with Peter Wadhams (https://e360.yale.edu/features/as_arctic_ocean_ice_disappears_global_climate_impacts_intensify_wadhams) that "the planet is swiftly heading toward a largely ice-free Arctic in the warmer months".

A BOE prediction of his will be proved right one melting season in the not too distant future, but probably not this one. IMHO!
Title: Re: The 2020 melting season
Post by: Neven on April 09, 2020, 01:21:31 PM
Announcement: I'm looking for people to take over as administrator of the ASIF. More info here (https://forum.arctic-sea-ice.net/index.php/topic,3033.msg258939.html).
Title: Re: The 2020 melting season
Post by: grixm on April 09, 2020, 02:28:31 PM
NSIDC Area Graphs.

Attached are the graphs for...
- Total Area
- the 7 High Arctic Seas Area,
- the 7 Peripheral Seas Area.
As one can see in the High Arctic melt has not started.

Also attached is Baffin Bay Sea Ice Area - now 2nd lowest in the satellite record, and currently the Poster Child for the 2020 melt season.

What is the significance of Baffin Bay for the larger picture?

I don´t think much so i am waiting for the other lines to change.

If not the arctic sea ice then I'm thinking at least it has an influence on Greenland melt.
Title: Re: The 2020 melting season
Post by: Jim Hunt on April 10, 2020, 01:26:23 PM
Would I be right in thinking that there is plenty of open water visible on the Ny Ålesund webcam?

http://GreatWhiteCon.info/resources/arctic-webcams/
Title: Re: The 2020 melting season
Post by: grixm on April 10, 2020, 01:31:23 PM
Would I be right in thinking that there is plenty of open water visible on the Ny Ålesund webcam?

http://GreatWhiteCon.info/resources/arctic-webcams/

Yes, you can see it from satellite too.

https://apps.sentinel-hub.com/sentinel-playground/?source=S2&lat=78.93059162916504&lng=11.968574523925781&zoom=12&preset=1-NATURAL-COLOR&layers=B01,B02,B03&maxcc=100&gain=0.4&gamma=1.0&time=2019-10-01%7C2020-04-08&atmFilter=&showDates=true
Title: Re: The 2020 melting season
Post by: Niall Dollard on April 10, 2020, 11:01:02 PM
Would I be right in thinking that there is plenty of open water visible on the Ny Ålesund webcam?


But this is the west coast of Spitzbergen which is predominantly ice free.

This year however there has been lots of ice even around the west coast.

The Svalbard sea ice area from the ice chart for 8th Apr 2020 is 493,166 sq km. This is 71,992 sq km above the 1981-2010 average and 8th highest area on record for this day of the year.
Title: Re: The 2020 melting season
Post by: Thomas Barlow on April 10, 2020, 11:10:33 PM
From 10th or 12th lowest extent just a week or so ago, to 3rd or 4th lowest today.

http://nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph
Title: Re: The 2020 melting season
Post by: Thomas Barlow on April 10, 2020, 11:19:20 PM
Paul Beckwith is a great wishful thinker.

I'm a wishful thinker too!

Could we possibly take the "alarmist"/"denialist" debate over to one of the Blue Ocean Event (https://forum.arctic-sea-ice.net/index.php/topic,2800.msg244868.html#msg244868) threads, and get back to the 2020 melting season in here?

For the record I agree with Peter Wadhams (https://e360.yale.edu/features/as_arctic_ocean_ice_disappears_global_climate_impacts_intensify_wadhams) that "the planet is swiftly heading toward a largely ice-free Arctic in the warmer months".

A BOE prediction of his will be proved right one melting season in the not too distant future, but probably not this one. IMHO!

Jumping in for fun.
Wadhams literally will never be right.
We are at least 20 years from a BOE for one week in summer (1/6 sea-ice extent in Arctic Ocean), and humans will either deplete into nothing, or evolve at uprecendented rate by then. Once humans are diminished greatly, Earth's CO2 and pollution control mechanisms will kick in 10-fold, and ice-extent will grow.
We must evolve...in the real sense of the word.

And yea, back to Melting Season now, thanks.
Title: Re: The 2020 melting season
Post by: Freegrass on April 11, 2020, 02:54:57 AM
More than 2°C yesterday in the laptev sea.

https://earth.nullschool.net/#2020/04/09/2100Z/wind/surface/level/overlay=temp/orthographic=-44.76,105.99,3000/loc=130.078,71.852
Title: Re: The 2020 melting season
Post by: interstitial on April 11, 2020, 03:50:09 AM
More than 2°C yesterday in the laptev sea.

https://earth.nullschool.net/#2020/04/09/2100Z/wind/surface/level/overlay=temp/orthographic=-44.76,105.99,3000/loc=130.078,71.852
That is air temperature.
Title: Re: The 2020 melting season
Post by: El Cid on April 11, 2020, 08:51:55 AM
Once humans are diminished greatly, Earth's CO2 and pollution control mechanisms will kick in 10-fold, and ice-extent will grow.
We must evolve...in the real sense of the word.

Now that is a major misunderstanding. Even if we stopped emittin all Co2 today, warming would continue for at least decades as Co2 stays in the atmosphere for quite long:
https://www.yaleclimateconnections.org/2010/12/common-climate-misconceptions-atmospheric-carbon-dioxide/

It turns out that while much of the “pulse” of extra CO2 accumulating in the atmosphere would be absorbed over the next century if emissions miraculously were to end today, about 20 percent of that CO2 would remain for at least tens of thousands of years.

Each year the chance of a BOE is bigger and with no aerosols due to COVID19 and a snowless winter in Europe, and the state of the ice as shown upthread and wintertime export of multiyear ice, this year is a very strong contender I believe
Title: Re: The 2020 melting season
Post by: grixm on April 11, 2020, 01:26:38 PM
I thought this was kind of cool. The low in the Barents sea currently has four mesovortices, creating a kind of fidget-spinner pattern:

(https://i.imgur.com/2iaFX6y.jpg)
Title: Re: The 2020 melting season
Post by: psymmo7 on April 11, 2020, 01:34:50 PM
mesovortex pattern indeed cool! Very fractal!
Title: Re: The 2020 melting season
Post by: Thomas Barlow on April 11, 2020, 01:46:35 PM
Once humans are diminished greatly, Earth's CO2 and pollution control mechanisms will kick in 10-fold, and ice-extent will grow.
We must evolve...in the real sense of the word.

Now that is a major misunderstanding. Even if we stopped emittin all Co2 today, warming would continue for at least decades as Co2 stays in the atmosphere for quite long:
https://www.yaleclimateconnections.org/2010/12/common-climate-misconceptions-atmospheric-carbon-dioxide/

Now that is a major misunderstanding (to quote you). If humans are not polluting for some magical reason, the mechanisms of nature that pull CO2 and pollution from the air, land, and sea, kick-in, and are always 10 times more cleansing and restorative than scientists' expect. These are the scientific facts, but that discussion and scientific references are for another thread, which I have little interest in that discusion.

<You can't state as scientific fact that natural mechanisms are 10 times what scientists expect. This requires major justification, in another thread, should you wish to stick to it.>
Title: Re: The 2020 melting season
Post by: Freegrass on April 11, 2020, 01:58:45 PM
More than 2°C yesterday in the laptev sea.

https://earth.nullschool.net/#2020/04/09/2100Z/wind/surface/level/overlay=temp/orthographic=-44.76,105.99,3000/loc=130.078,71.852
That is air temperature.
Yes I know. Spring in the Laptev.
Title: Re: The 2020 melting season
Post by: Freegrass on April 11, 2020, 02:05:59 PM
...about 20 percent of that CO2 would remain for at least tens of thousands of years.
It will take nature millions of years to store all that carbon back into fossilized or crystalline form.
Title: Re: The 2020 melting season
Post by: Davidsf on April 11, 2020, 04:00:00 PM
I nominate mesovortices for word of the month  :D
Title: Re: The 2020 melting season
Post by: Thomas Barlow on April 11, 2020, 08:22:44 PM
Once humans are diminished greatly, Earth's CO2 and pollution control mechanisms will kick in 10-fold, and ice-extent will grow.
We must evolve...in the real sense of the word.

Now that is a major misunderstanding. Even if we stopped emittin all Co2 today, warming would continue for at least decades as Co2 stays in the atmosphere for quite long:
https://www.yaleclimateconnections.org/2010/12/common-climate-misconceptions-atmospheric-carbon-dioxide/

Now that is a major misunderstanding (to quote you). If humans are not polluting for some magical reason, the mechanisms of nature that pull CO2 and pollution from the air, land, and sea, kick-in, and are always 10 times more cleansing and restorative than scientists' expect. These are the scientific facts, but that discussion and scientific references are for another thread, which I have little interest in that discusion.

<You can't state as scientific fact that natural mechanisms are 10 times what scientists expect. This requires major justification, in another thread, should you wish to stick to it.>

Everyone does that here.
But the new moderators are fake-name lurkers with no real personage. Basically hiding behind their fake names. Angry, cilique-forming, prejudiced trolls at best.

I have the research for what I said. It's like asking for evidence that the Earth is round. But I'm outta here, now that 'seaicesailor' or some other fake guy is moderating with their latest fake-name, after they got banned several times in the past. Not interested.
Title: Re: The 2020 melting season
Post by: Jim Hunt on April 11, 2020, 08:54:35 PM
Thomas - Please take all your non "2020 melting season" comments elsewhere.

TIA
Title: Re: The 2020 melting season
Post by: Wildcatter on April 12, 2020, 03:38:50 AM
Cyclone system going to spawn in the Fram/Greenland Sea in 2 days. Going to be a doozy, gets stuck under a ridge for at least 3 days. Warmth + winds and warm water coming to the Barents and ice pack on that side, starts stretching a good ways into the CAB. Nullschool only goes 5 days, and it's still there.

Here's Day 4, you can change days at the bottom with the << >> arrows.
https://earth.nullschool.net/#2020/04/15/1800Z/wind/surface/level/overlay=temp/orthographic=-77.81,80.15,450/loc=54.814,78.149 (https://earth.nullschool.net/#2020/04/15/1800Z/wind/surface/level/overlay=temp/orthographic=-77.81,80.15,450/loc=54.814,78.149)

Eurasia is also probably going to see a lot of snow melt. Especially the eastern side, warming up quickly. A lot of warmth has been pulsing through Eurasia. I'm not sure what the records are, but snow extent + April warmth will probably be notable. Warm Barents + warm Eurasia behind it.

Extreme cold retreating from the Bering and Western NA. Baffin probably going to get dinged a bit too. 2020 will assuredly be 2nd lowest pretty soon. April is looking like it's going to be very interesting.
Title: Re: The 2020 melting season
Post by: binntho on April 12, 2020, 06:05:30 AM
Good moderating there Oren!
Title: Re: The 2020 melting season
Post by: VaughnAn on April 12, 2020, 07:15:05 AM
Good moderating there Oren!

Oren may have a little more moderating to do.  See comment #269 upthread.  BTW, oren, good to see you as moderator.
Title: Re: The 2020 melting season
Post by: Jim Hunt on April 12, 2020, 08:26:23 AM
Oren may have a little more moderating to do.  See comment #269 upthread.

I thought that as well!

The "Skeptical Science style" of moderation has a lot to recommend it, if you have the time to do it well.

Thanks Oren.
Title: Re: The 2020 melting season
Post by: oren on April 12, 2020, 08:50:55 AM
I've decided to let #269 stand, in all its dubious glory, as I'm more concerned with denialism of science than with silly insults. However TB is on my radar screen, should this continue.
Title: Re: The 2020 melting season
Post by: nanning on April 12, 2020, 09:01:12 AM
Thank you oren for your moderation in moderating. Much appreciated.

"nanning" is my first given name. Is "oren" your first name? Just nice to know.
Title: Re: The 2020 melting season
Post by: oren on April 12, 2020, 09:34:00 AM
 Actually yes, it is.
Title: Re: The 2020 melting season
Post by: psymmo7 on April 12, 2020, 10:14:21 AM
Well moderated Oren
Title: Re: The 2020 melting season
Post by: jdallen on April 12, 2020, 11:44:45 AM
More than 2°C yesterday in the laptev sea.

https://earth.nullschool.net/#2020/04/09/2100Z/wind/surface/level/overlay=temp/orthographic=-44.76,105.99,3000/loc=130.078,71.852
That is air temperature.
Yes, but it means heat is flowing the wrong way, earlier than it should be (no freezing).

It also means top melt of the covering snow pack, potential formation of sub-snow cover melt ponding, and a general reduction in albedo.

It all adds up.
Title: Re: The 2020 melting season
Post by: Pavel on April 12, 2020, 01:38:17 PM
Air temperature in Tiksi (the Laptev coast) was 21.2 C above average that day. Heat waves will continue in Siberian side. Meanwhile almost 500 Gt of snow melted out in Eurasia in just 11 days. It's more than Greenland melt in whole season
Title: Re: The 2020 melting season
Post by: Freegrass on April 12, 2020, 02:06:47 PM
More than 2°C yesterday in the laptev sea.

https://earth.nullschool.net/#2020/04/09/2100Z/wind/surface/level/overlay=temp/orthographic=-44.76,105.99,3000/loc=130.078,71.852
That is air temperature.
Yes, but it means heat is flowing the wrong way, earlier than it should be (no freezing).

It also means top melt of the covering snow pack, potential formation of sub-snow cover melt ponding, and a general reduction in albedo.

It all adds up.
That heat was actually very weirdly narrow and local. I guess that has to do with the mountains there and the Lena river valley that channels the wind?  If you go through the different heights on Nullschool on that day, a lot of that heat comes in on the 850 hPa level, and then weirdly appeared on the Laptev at the surface level.

https://earth.nullschool.net/#2020/04/09/2100Z/wind/isobaric/1000hPa/overlay=temp/orthographic=-44.76,105.99,1500/loc=130.078,71.852
Title: Re: The 2020 melting season
Post by: Shared Humanity on April 12, 2020, 04:12:04 PM
Good moderating there Oren!

Neven has been overworked for years. I have always felt a deep debt of gratitude that he has spent so much of his life on this. There are a lot of people here who I respect a great deal. Oren is one of these people. Moderation can only improve with several persons like him/her here.
Title: Re: The 2020 melting season
Post by: Shared Humanity on April 12, 2020, 04:16:02 PM
I have the research for what I said.

Linked research is one of the biggest reasons I am a regular here. Could you provide the link on the BOE thread?
Title: Re: The 2020 melting season
Post by: Thomas Barlow on April 12, 2020, 04:34:31 PM
Oren may have a little more moderating to do.  See comment #269 upthread.

I thought that as well!

The "Skeptical Science style" of moderation has a lot to recommend it, if you have the time to do it well.

Thanks Oren.

I'm a science-denier now?
I've been at this far longer than most here. Here's my message from 1996 to the Paris Climate Conference, long before most of you jumped on the climate bandwagon, after most of you denyied it for years in the 80s and 90s.
https://postimg.cc/PPLxMBCP
Title: Re: The 2020 melting season
Post by: oren on April 12, 2020, 04:52:47 PM
TB, I hope you can cool down and not take offense. But I also ask you to continue any further discussions of moderation actions to the Forum Decorum thread.
Title: Re: The 2020 melting season
Post by: blumenkraft on April 12, 2020, 07:07:04 PM
Ok, let's do some serious stuff for a change, shall we?

Here is the series of Sunday movies. Starting with the Ozone concentration Sunday to Sunday, 8 frames.
Title: Re: The 2020 melting season
Post by: blumenkraft on April 12, 2020, 07:08:26 PM
The Fram export via SAR. Saturday to Sunday, 9 frames (because last Sunday flight path sucked).
Title: Re: The 2020 melting season
Post by: blumenkraft on April 12, 2020, 07:09:29 PM
Ice drift map, Sunday to Saturday, 7 frames.
Title: Re: The 2020 melting season
Post by: blumenkraft on April 12, 2020, 07:10:46 PM
And the 7-day hindsight mean temperature anomalies, Sunday to Sunday, 8 frames.
Title: Re: The 2020 melting season
Post by: Freegrass on April 12, 2020, 11:06:33 PM
Good moderating there Oren!

Neven has been overworked for years. I have always felt a deep debt of gratitude that he has spent so much of his life on this. There are a lot of people here who I respect a great deal. Oren is one of these people. Moderation can only improve with several persons like him/her here.
I found Neven to be a down to earth, and generous person. I had my bad days here on the forum, and they still count...  But Neven dealt with it respectfully! And I can only bow my head to such grace...

I hope you can keep those people in your dad's business @work Neven! I know it'll be difficult, because you'll have to set aside some of your principles if you want to run a business... But I know you'll make it work after you've finished doing your damage control! Business is all about people knowledge, and you know people!

I wish you all the best! And I mean that! What you did here is awesome! THANK YOU!
Oren and Blum will be good moderators.

Sometimes you have to let things go for them to flourish... But you'll always be the one who provided the seed...

Good Luck!
And many thanks!
Title: Re: The 2020 melting season
Post by: Freegrass on April 12, 2020, 11:24:00 PM
Ice drift map, Sunday to Saturday, 7 frames.
That Ice in the Barents is gonna get a push-back in the coming days.

https://earth.nullschool.net/#2020/04/15/1200Z/wind/surface/level/orthographic=-45.02,91.24,1723/loc=77.846,82.786

And if the predictions hold up again, the CAP will have its first defrosting of the season in 4 or 5 days from now.

https://earth.nullschool.net/#2020/04/16/1200Z/wind/surface/level/overlay=temp/orthographic=-45.02,91.24,2274/loc=77.443,84.616

A lot of energy is entering the arctic...

https://earth.nullschool.net/#2020/04/16/1200Z/wind/surface/level/overlay=total_precipitable_water/orthographic=-45.02,91.24,1723

Title: Re: The 2020 melting season
Post by: Freegrass on April 13, 2020, 01:04:11 AM
I don't get it. How can this scale be in cm? Shouldn't that be decimeter? 72 cm is less than a meter. 70 dm is 7m.

Not much snow in Siberia, is there? But I'm pretty sure that's more than 2 cm...

Edit: 420 messages... Happy 420!  ;D
Title: Re: The 2020 melting season
Post by: Wildcatter on April 13, 2020, 05:54:47 AM
Warmer weather over western NA (including Alaska) looks like it's going to lead to an enormous amount of snow melt this week. Wow.
Title: Re: The 2020 melting season
Post by: binntho on April 13, 2020, 06:10:18 AM
I don't get it. How can this scale be in cm? Shouldn't that be decimeter? 72 cm is less than a meter. 70 dm is 7m.

Snow is rarely very thick in flat areas without tree cover. The wind tends to blow it away, but of course there can be very deep accumulations where an obstruction gives some shelter.

The very deepest even snow layer I ever saw was about 2 m, covering a flat valley floor perhaps 2 or 3 km wide. The surrounding mountains were mostsly windswept and bare, so averaging over the entire area would probably be well under 1m.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on April 13, 2020, 07:05:32 AM
I only glanced at the next 10 days.

Does look like the Canadian basin.

Expecially the CAA should see very good conditions for thickening.
Title: Re: The 2020 melting season
Post by: jdallen on April 13, 2020, 09:27:52 AM
More than 2°C yesterday in the laptev sea.
That is air temperature.
Yes, but it means heat is flowing the wrong way, earlier than it should be (no freezing).
That heat was actually very weirdly narrow and local. I guess that has to do with the mountains there and the Lena river valley that channels the wind?

You may be on to something there.  It might be adiabatic heating due to air compressing from being driven over and then down the opposite side of a mountain range.
Title: Re: The 2020 melting season
Post by: oren on April 13, 2020, 09:59:02 AM
Temps in Tiksi have been experiencing a heatwave in the past 9 days. The two days that were above zero hit record high temperatures for the date.
Title: Re: The 2020 melting season
Post by: Aluminium on April 13, 2020, 10:39:56 AM
April 5-12.

2019 (https://forum.arctic-sea-ice.net/index.php/topic,2591.msg194758.html#msg194758).
Title: Re: The 2020 melting season
Post by: pearscot on April 13, 2020, 06:28:44 PM
I'm hyper interested in witnessing what unfolds on Greenland's northern shoreline this year, but I really think that the crack that formed last year will become a new feature. While still early in the melt season, I looks as though the pack is quite mobile already and once more widespread melt and Atlantification kick in, I think this area will melt somewhat quickly. This is from the April 12th(!)


Title: Re: The 2020 melting season
Post by: Gumbercules on April 13, 2020, 06:41:27 PM
Oren may have a little more moderating to do.  See comment #269 upthread.

I thought that as well!

The "Skeptical Science style" of moderation has a lot to recommend it, if you have the time to do it well.

Thanks Oren.

Wouldn't want any wrongthink now would we?

<No, we wouldn't. O.>
Title: Re: The 2020 melting season
Post by: Freegrass on April 13, 2020, 09:57:09 PM
I don't get it. How can this scale be in cm? Shouldn't that be decimeter? 72 cm is less than a meter. 70 dm is 7m.

Snow is rarely very thick in flat areas without tree cover. The wind tends to blow it away, but of course there can be very deep accumulations where an obstruction gives some shelter.

The very deepest even snow layer I ever saw was about 2 m, covering a flat valley floor perhaps 2 or 3 km wide. The surrounding mountains were mostsly windswept and bare, so averaging over the entire area would probably be well under 1m.
Well that's why I find it weird that the scale only goes to 72 cm, when there are clearly places with a lot more snow than that. I understand that snow can get blown away, but 1 or 2 cm of snow is nothing. That's 1 hour or less of snow. Surely there must be more?

But I guess the people who made that site must know what they are doing. I just find it odd... Can we say that Siberia is like a desert, with very little precipitation? Is that why I'm understanding snow cover in Siberia and the Arctic wrong?
Title: Re: The 2020 melting season
Post by: oren on April 13, 2020, 10:05:46 PM
Freegrass, best continue this dicussion in the NH snow cover thread.
https://forum.arctic-sea-ice.net/index.php/topic,2876.msg259533.html#new (https://forum.arctic-sea-ice.net/index.php/topic,2876.msg259533.html#new)
Title: Re: The 2020 melting season
Post by: Burnrate on April 14, 2020, 05:48:12 AM
I know there have been some posts about the aerosol reduction impacting the arctic ice melt but I wanted to discuss it a bit again with some more background available.

I thought the video linked at the end shared some research papers that had very interesting information about the short term effects of the aerosol reduction and how it might affect this melting season.

Basically it says most of the temperature increase will be over the arctic and other parts of the northern hemisphere.  There will also be a large increase in precipitation and more volatile weather.

Depending on the severity of the aerosol reduction it will be interesting to see if we can tease out the impacts on the melting season.  A lot of rain and storms perhaps?

(https://i.imgur.com/dJ4xYmX.jpg)

This is the video.  The part showing the image from this post starts at 10 minutes.  I think the video does a great job of discussing all the different things that go on and the history of the research into aerosol reduction.
https://youtu.be/emn1hBSHUfQ (https://youtu.be/emn1hBSHUfQ)
Title: Re: The 2020 melting season
Post by: SimonF92 on April 14, 2020, 01:05:57 PM
We wrote a program in the developers-corner that can extract data from the MOSAiC buoys in (essentially) real time.

Ill be posting that data weekly to a dropbox in the format of both raw-numerical and visual data.

It will be interesting to keep an eye on them over the melt-season, it already appears that temps are ramping up over all the active buoys we can monitor.

Uniquorn has been working their magic in making some cartographic visualisations over in the MOSAiC thread.
Title: Re: The 2020 melting season
Post by: Freegrass on April 14, 2020, 02:48:34 PM
It might be adiabatic heating due to air compressing from being driven over and then down the opposite side of a mountain range.
It looks like you can see another good example of adiabatic heating around Novaya Zemlya. That is so cool.

https://earth.nullschool.net/#2020/04/19/0600Z/wind/surface/level/overlay=temp/orthographic=-45.02,91.24,3000/loc=63.371,76.884
Title: Re: The 2020 melting season
Post by: gerontocrat on April 14, 2020, 05:41:22 PM
Early days but here is a look at Nico Sun's Albedo Warming Potential  Graphs.

The first graph shows the Cumulative Total anomaly & 2020 is off to am early start. The second graph shows how this early start is mainly due to just 3 peripheral seas - Okhotsk, Bering & Baffin.

The first graph also is a good demo of how the 2012 melt, being so late was not so effective in raising the AWP as in 2016 and 2019. With less warmth accumulated, 2012 saw a very rapid and early freeze, in contrast with 2016 and 2019. Remember the lack of freeze in October 2019?

Even if confined to the periphery, early melt must surely make a difference, though perhaps more to fall and early winter.
Title: Re: The 2020 melting season
Post by: Aluminium on April 14, 2020, 06:24:53 PM
Warm weather enters into the Arctic.
Title: Re: The 2020 melting season
Post by: Tor Bejnar on April 14, 2020, 06:49:51 PM
Almost warm enough to sunbathe on the Polarstern.
 :D
Title: Re: The 2020 melting season
Post by: jdallen on April 14, 2020, 08:43:14 PM
Warm weather enters into the Arctic.
That's one *helluva* temperature gradient.  I imagine weather's kind of unsettled a few hundred KM N of Svalbard.
Title: Re: The 2020 melting season
Post by: Paul on April 14, 2020, 08:51:50 PM
Warm weather enters into the Arctic.

Yep a pattern change of a spell of southerlies for the fram Stright and the Barants sea, the strongest winds don't look set too last ffor too long but it is bringing well above average temperatures. I guess in one way its not too bad for the ice as it gets pushed back northwards and it compacts but we see if we see much in the way of extent lost in the Barants as a result.
Title: Re: The 2020 melting season
Post by: Freegrass on April 14, 2020, 09:43:52 PM
Five day forecast
Wind + Temp @ Surface
Title: Re: The 2020 melting season
Post by: Niall Dollard on April 15, 2020, 12:29:37 AM
I'm hyper interested in witnessing what unfolds on Greenland's northern shoreline this year, but I really think that the crack that formed last year will become a new feature.

I was wondering if this year the blocked Nares might make the ice more stable directly north of Greenland - compared to last year spring/summer.

The latest PIOMAS chart seemed to indicate thicker ice in this area this year.

Although having said that, this GIF from June 2016 shows that even with a blocked Nares Strait (bottom left) cracks can develop right across the north of Greenland.
Title: Re: The 2020 melting season
Post by: Niall Dollard on April 15, 2020, 01:35:46 AM
Almost warm enough to sunbathe on the Polarstern.

Recent temperature and wind direction plot from Polarstern.

At 14.04.2020 22:00 (local time) it was -14.5 C but rise in temperature is clear.

Wind has backed all the way from northerly around to an easterly direction.

I think I would wait a while before sunbathing.  :)
Title: Re: The 2020 melting season
Post by: Glen Koehler on April 15, 2020, 06:20:27 AM
I don't get it. How can this scale be in cm? Shouldn't that be decimeter? 72 cm is less than a meter. 70 dm is 7m.
Not much snow in Siberia, is there? But I'm pretty sure that's more than 2 cm...

Dr. Sean Birkel (who singlehandedly conceived, built, and runs Climate Reanalyzer) sent me this reply about the legend on the snow depth map:
"The plotted units were inches, while the title showed cm.  Found bug...now the plotted values are in cm set to a cm specific color scale."

   Thus, before the correction the snow depth indicated was only 40% of the actual.  Now corrected.
Title: Re: The 2020 melting season
Post by: nanning on April 15, 2020, 07:43:30 AM
Thanks for that information and your effort Glen.

All hail Sean Birkel!
Let's send him (I think 'Sean' is male) a bunch of flowers or somesuch.
Title: Re: The 2020 melting season
Post by: Freegrass on April 15, 2020, 09:28:22 AM
I don't get it. How can this scale be in cm? Shouldn't that be decimeter? 72 cm is less than a meter. 70 dm is 7m.
Not much snow in Siberia, is there? But I'm pretty sure that's more than 2 cm...

Dr. Sean Birkel (who singlehandedly conceived, built, and runs Climate Reanalyzer) sent me this reply about the legend on the snow depth map:
"The plotted units were inches, while the title showed cm.  Found bug...now the plotted values are in cm set to a cm specific color scale."

   Thus, before the correction the snow depth indicated was only 40% of the actual.  Now corrected.
That's awesome. Thanks Glen! And thank you Dr. Sean Birkel for the work on Climate Reanalyzer. Happy I was able to find this bug. :)
Title: Re: The 2020 melting season
Post by: Pavel on April 15, 2020, 01:52:04 PM
Ice melting in the Barents sea due to the strong cyclone and heat advection. Animation yesterday/today
Title: Re: The 2020 melting season
Post by: Milwen on April 15, 2020, 08:01:39 PM
(https://i.imgur.com/LZcuJMl.png)
Title: Re: The 2020 melting season
Post by: Milwen on April 15, 2020, 08:11:27 PM
Also this doesnt look good https://worldview.earthdata.nasa.gov/?v=-2221358.499810497,1162240.0000000005,-1238318.4998104968,1678848.0000000005&p=arctic&t=2020-04-13-T17%3A58%3A09Z&l=Graticule,Reference_Labels(hidden),Reference_Features(hidden),Coastlines,VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor,MODIS_Terra_CorrectedReflectance_TrueColor (https://worldview.earthdata.nasa.gov/?v=-2221358.499810497,1162240.0000000005,-1238318.4998104968,1678848.0000000005&p=arctic&t=2020-04-13-T17%3A58%3A09Z&l=Graticule,Reference_Labels(hidden),Reference_Features(hidden),Coastlines,VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor,MODIS_Terra_CorrectedReflectance_TrueColor)
Title: Re: The 2020 melting season
Post by: jdallen on April 15, 2020, 10:00:18 PM
Also this doesnt look good https://worldview.earthdata.nasa.gov/?v=-2221358.499810497,1162240.0000000005,-1238318.4998104968,1678848.0000000005&p=arctic&t=2020-04-13-T17%3A58%3A09Z&l=Graticule,Reference_Labels(hidden),Reference_Features(hidden),Coastlines,VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor,MODIS_Terra_CorrectedReflectance_TrueColor (https://worldview.earthdata.nasa.gov/?v=-2221358.499810497,1162240.0000000005,-1238318.4998104968,1678848.0000000005&p=arctic&t=2020-04-13-T17%3A58%3A09Z&l=Graticule,Reference_Labels(hidden),Reference_Features(hidden),Coastlines,VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor,MODIS_Terra_CorrectedReflectance_TrueColor)

Yeah, quickly sifted through images of the same location over the last 10 years.  The ice in the Chukchi is noticeably worse than previous years.  ESS looks about the same over all, somewhat worse than average.  The combination of them may be a portent, but we'll need to watch for more strong weather and/or melt ponds before we get too excited about it.
Title: Re: The 2020 melting season
Post by: Freegrass on April 15, 2020, 10:19:45 PM
The polar vortex is about to split up. 

I've moved this to the proper thread. I'm gonna try to do better with this.

https://forum.arctic-sea-ice.net/index.php/topic,704.msg236659.html#msg236659
Title: Re: The 2020 melting season
Post by: wdmn on April 15, 2020, 11:53:19 PM
Also this doesnt look good https://worldview.earthdata.nasa.gov/?v=-2221358.499810497,1162240.0000000005,-1238318.4998104968,1678848.0000000005&p=arctic&t=2020-04-13-T17%3A58%3A09Z&l=Graticule,Reference_Labels(hidden),Reference_Features(hidden),Coastlines,VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor,MODIS_Terra_CorrectedReflectance_TrueColor (https://worldview.earthdata.nasa.gov/?v=-2221358.499810497,1162240.0000000005,-1238318.4998104968,1678848.0000000005&p=arctic&t=2020-04-13-T17%3A58%3A09Z&l=Graticule,Reference_Labels(hidden),Reference_Features(hidden),Coastlines,VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor,MODIS_Terra_CorrectedReflectance_TrueColor)

Perfect example of why those who think extent is the more important metric than volume are lost in abstract land. As thickness (volume) declines, the structural integrity of the ice declines. Rapid declines in extent occur only after the structural integrity of the ice has already been compromised. Until the structural integrity of ice is compromised declines in extent are minimal. We will see the Chukchi melt out rapidly this year because the ice is already compromised.
Title: Re: The 2020 melting season
Post by: Phoenix on April 16, 2020, 12:11:34 AM

Perfect example of why those who think extent is the more important metric than volume are lost in abstract land. As thickness (volume) declines, the structural integrity of the ice declines. Rapid declines in extent occur only after the structural integrity of the ice has already been compromised. Until the structural integrity of ice is compromised declines in extent are minimal. We will see the Chukchi melt out rapidly this year because the ice is already compromised.

What's the most objective way of comparing the degree of compromise from year to year? In the absence of any other evidence, I would probably look at the Chukchi area figures at equivalent dates in 2019 and 2020 as an indication of the degree of Chukchi decline in structural integrity.
Title: Re: The 2020 melting season
Post by: wdmn on April 16, 2020, 01:31:36 AM
Decline in area won't get you that, because in regional seas that melt out every year it's highly dependent on other factors. But this is a bit of a red herring.

We have volume data for arctic sea ice (imperfect as it may be). So when we're trying to project how sea ice decline will go over time, we're not looking at areas that melt out every year already anyway (by that point those areas are already lacking thick ice). My point was simply that the photo shows (what people frequenting the board already know) how sea ice actually melts out; not from the edges in, but first through the loss of integrity of the ice; i.e. through loss in thickness/volume. Large declines in area/extent only show up afterwards.

Structural integrity can be weakened through other processes than bottom and surface melt, so -- as 2012 demonstrated -- there are ways to speed up the process of getting to lower extent, of course.
Title: Re: The 2020 melting season
Post by: Paul on April 16, 2020, 01:41:31 AM
Also this doesnt look good https://worldview.earthdata.nasa.gov/?v=-2221358.499810497,1162240.0000000005,-1238318.4998104968,1678848.0000000005&p=arctic&t=2020-04-13-T17%3A58%3A09Z&l=Graticule,Reference_Labels(hidden),Reference_Features(hidden),Coastlines,VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor,MODIS_Terra_CorrectedReflectance_TrueColor (https://worldview.earthdata.nasa.gov/?v=-2221358.499810497,1162240.0000000005,-1238318.4998104968,1678848.0000000005&p=arctic&t=2020-04-13-T17%3A58%3A09Z&l=Graticule,Reference_Labels(hidden),Reference_Features(hidden),Coastlines,VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor,MODIS_Terra_CorrectedReflectance_TrueColor)

Yeah, quickly sifted through images of the same location over the last 10 years.  The ice in the Chukchi is noticeably worse than previous years.  ESS looks about the same over all, somewhat worse than average.  The combination of them may be a portent, but we'll need to watch for more strong weather and/or melt ponds before we get too excited about it.

2014 looks similar around that date but as we know, the ice could look different within the next few days and there is no major dramas forecast for the Chukchi for the foreseeable future.

Disagree about the ESS, the lack of fast ice is a real concern, if the weather was as bad as last June we may see a rapid melt out here. I think we may see just how shocking the ESS will be if we keep getting winds blowing in from Siberia and watch the gaps between the fast ice and the sea ice growing. 2017 was quite extreme and I would not be surprised if we see something similar this year.
Title: Re: The 2020 melting season
Post by: oren on April 16, 2020, 08:12:57 AM
The Chukchi continues to follow the custom post-2016 of starting the melting season with a low volume. But 2018 and 2019 were even worse.
Title: Re: The 2020 melting season
Post by: wallen on April 16, 2020, 01:35:45 PM
I know am a novice at this, but cracking in various directions to this extent deep in the CAB, I would think is very concerning, this early in the melting season. See Worldview 16/4 towards the pole from the ESS.  Would ad a pic but not good at this...yet.
Title: Re: The 2020 melting season
Post by: Freegrass on April 16, 2020, 02:17:11 PM
I've made another forecast video with Wind + Temp @ Surface. The heat that's coming into the arctic in the coming days is impressive. The Bering sea will also go through some melting.

I usually put these videos on loop (right click, and select loop), that way you can focus on an area and get the forecast for it, or just watch how the cold gets blown away...
Title: Re: The 2020 melting season
Post by: Pavel on April 16, 2020, 02:44:43 PM
The open water may extend to the Pole in Siberian side in September if such pattern will continue. The Laptev/ESS ice is already thin + early surface melting and quick land snow retreat in Siberia
Title: Re: The 2020 melting season
Post by: PragmaticAntithesis on April 16, 2020, 03:26:51 PM
The open water may extend to the Pole in Siberian side in September if such pattern will continue. The Laptev/ESS ice is already thin + early surface melting and quick land snow retreat in Siberia

If that happens, would it be the first time the pole melts?
Title: Re: The 2020 melting season
Post by: Freegrass on April 16, 2020, 04:08:16 PM
The open water may extend to the Pole in Siberian side in September if such pattern will continue. The Laptev/ESS ice is already thin + early surface melting and quick land snow retreat in Siberia
That we're gonna have another disastrous year for the ice is without question. The only unknown is the weather. If we get a lot of wind stirring up the ocean, mixing layers, coupled with a lot of export through fram and the garlic press, then we could see open water at the pole and more. But like I said, it'll all depend on the weather...

My guess is that it's gonna be bad!
Title: Re: The 2020 melting season
Post by: Phoenix on April 16, 2020, 07:10:02 PM

That we're gonna have another disastrous year for the ice is without question. The only unknown is the weather.....


Help me understand these statements Freegrass. If we are definitely going to have a disastrous year for the ice and the only unknown is weather, what is not unknown? What are the non-weather factors which are important to the outcome for the ice this year?
Title: Re: The 2020 melting season
Post by: RikW on April 16, 2020, 07:21:42 PM
well, the last 10/20 years have been disastrous compared to what was normal and this year won't be different I guess; How disastrous it will be, depends, among other things, on the weather
Title: Re: The 2020 melting season
Post by: Freegrass on April 16, 2020, 08:23:31 PM
well, the last 10/20 years have been disastrous compared to what was normal and this year won't be different I guess; How disastrous it will be, depends, among other things, on the weather
What Rick said Phoenix. We know what the long term trend is, and we can already see the bad shape the ice is in this year. So the only unknown now is the weather.
Title: Re: The 2020 melting season
Post by: Burnrate on April 16, 2020, 10:54:10 PM
This is why I think any aerosol loss will be significant.  It's major effect is increasing the atmospheric heat and precipitation in the arctic.  More storms, more wind, more rain on the ice.  Bad weather from the plague!
Title: Re: The 2020 melting season
Post by: jdallen on April 17, 2020, 05:06:08 AM
The open water may extend to the Pole in Siberian side in September if such pattern will continue. The Laptev/ESS ice is already thin + early surface melting and quick land snow retreat in Siberia

If that happens, would it be the first time the pole melts?
Probably for the first time in about 3 million years, yes.
Title: Re: The 2020 melting season
Post by: tybeedave on April 17, 2020, 05:48:43 AM
hi yall,
it's been a few days since i posted. i've been practicing what i preach, that is, i've watched and listened and kept my mouth shut when i had nothing nice or important to say.  bear with me as i wax poetic.
for some of you, i am ringing a familiar bell or chime.  for others, i am scratching my fingernails on a blackboard.
we don't contribute to this forum because the data and opinions are just interesting (at least i don't).  we're here because we're horrified at the state of the sea ice and the tragedy it portends.
we all are trying to contribute to understanding what's happening now so that it may help us modify our future. 
i've included a pic for reference in my contribution to a possible understanding leading to a solution.
(https://forum.arctic-sea-ice.net/proxy.php?request=http%3A%2F%2F&hash=35d7d5d7526c9897dfb55501e320295a)
pls feel free to suggest additions or omissions

Contributing factors of sea ice decline beyond the sun which ultimately drives all the others
all may be acute or chronic
all should be paid attention to when approaching extreme levels or timeframes.
pray when more than one happens at the same time
i offer no evidence, i cite no data, just a view of what i look at in no particular order of importance after the sun

O.  the sun's heat and the weather it creates.  last year's sunshine seemed extreme in the spring but not so much the rest of the melt season.
1.  the CAB being attacked from underneath. insidious.
2.  the extreme melt event currently occurring in the fram/greenland sea area.
3.  the atlantification by gulf stream heat transfer to the far north
4.  the heat imported from the Pacific in pulses that are much stronger than the occasional wind shift caused export.  warm in, cool out.
5.  the freshness of the top layer of liquid water in the Beaufort Sea and salinity levels elsewhere.
6.  the sometimes export of ice thru the Nares and the continuous flow of cold water yr-round that is replaced in the CAB by warmer waters from the Atlantic and Pacific.
7.  American and Russian exploitation of natural resources and the footprints they leave.
8.  currents spreading the Atlantic warmth around the periphery, ie, as a kid, Novaya Zemlya (new land) was icebound all summer, this year, open water existed all winter on at least one side of the island
9  the melting of Greenland proper, it was extreme last year and may repeat, the cracks visible last year on its northern coast seem about to repeat.
10.  the CAA, the last bastion of multiyear ice.  it was extremely cold this past winter, but it is still fragile.

correct me, i'm sure i missed a few factors in melt analysis (the wind event in 2012), ie, tides as so recently cited by MOSAIC observations of its decaying effect on the sea ice in their location, but my aim is to ring an alarm bell and move us all to action rather than guessing what an out of control future may be.

ps, ty Neven for the years of intelligent guidance, the king is dead, long live the king, oren, who is sure to lead us to greater heights of understanding.  ty in advance.  moderating is not easy, this i know from years of experience as a sysop and moderator for microsoft. my hat is off to you and all the contributors to this forum, even binntho, love ya man.  lol

td

Title: Re: The 2020 melting season
Post by: Phoenix on April 17, 2020, 06:49:34 AM
well, the last 10/20 years have been disastrous compared to what was normal and this year won't be different I guess; How disastrous it will be, depends, among other things, on the weather
What Rick said Phoenix. We know what the long term trend is, and we can already see the bad shape the ice is in this year. So the only unknown now is the weather.

The data thread says extent is 206k greater than last year at this point. There is no objective measure that I'm aware of the ice being in worse shape this year vs. last. The intermediate trend is that we haven't really come close to a new record minima for seven years.

I guess disaster is a subjective term. If 2020 matches 2019, is 2020 considered a disaster in your opinion? What are the criteria for disaster in the context of this season which is ostensibly the  thread topic?
Title: Re: The 2020 melting season
Post by: Aluminium on April 17, 2020, 09:30:24 AM
April 10-16.

2019 (https://forum.arctic-sea-ice.net/index.php/topic,2591.msg195759.html#msg195759).
Title: Re: The 2020 melting season
Post by: oren on April 17, 2020, 10:01:04 AM
April 10-16.
Looking at this animation (thank you as usual Aluminium), I think the recent weather in the Barents is actually good for the ice. The worst that can happen in April, when temps are still far below and the sun mostly nonexistent, is not a couple of days of barely-melting temps, but the continued and sustained movement of ice from the Pole region to the Fram, which reduces the amount of thick 2m+ ice that can resist a whole melting season. Anything that halts or slows down this freight train is welcome news, IMHO.
The longer the movement over time, the thicker the ice that is lost. Random walk does almost nothing in this regard.
Admittedly though, a few days of shakeup can dislodge stubborn ice or compact it and increase mobility of the pack, so it can cut both ways. We shall see.
Title: Re: The 2020 melting season
Post by: Hefaistos on April 17, 2020, 12:44:05 PM
The open water may extend to the Pole in Siberian side in September if such pattern will continue. The Laptev/ESS ice is already thin + early surface melting and quick land snow retreat in Siberia

If that happens, would it be the first time the pole melts?
Probably for the first time in about 3 million years, yes.

The significance of a pole melt would be mainly psychological.
Title: Re: The 2020 melting season
Post by: Pavel on April 17, 2020, 01:04:26 PM
Fram export will reduce but also polynyas are opening up in the CAB because of ice movement. From the weather forecast one can expect the polynyas won't refreeze but rather expand more
Title: Re: The 2020 melting season
Post by: Jim Hunt on April 17, 2020, 01:06:32 PM
Probably for the first time in about 3 million years, yes.

Not exactly JD:

http://GreatWhiteCon.info/2016/09/santa-extends-his-secret-summer-swimming-pool/
Title: Re: The 2020 melting season
Post by: The Walrus on April 17, 2020, 03:28:31 PM
The open water may extend to the Pole in Siberian side in September if such pattern will continue. The Laptev/ESS ice is already thin + early surface melting and quick land snow retreat in Siberia

If that happens, would it be the first time the pole melts?
Probably for the first time in about 3 million years, yes.

Possibly, although some have suggested that it may been as recently as 100,000 years ago.

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2013GL057188
https://www.independent.co.uk/environment/climate-change/arctic-could-become-ice-free-for-first-time-in-more-than-100000-years-claims-leading-scientist-a7065781.html

Others as recently as 6,000 years ago.

https://www.sciencedirect.com/science/article/pii/S0277379113004162?np=y
https://phys.org/news/2008-10-ice-arctic-ocean-years.html

Title: Re: The 2020 melting season
Post by: Niall Dollard on April 17, 2020, 03:46:31 PM
Close up Worldview image of Sept 8th 2016
Title: Re: The 2020 melting season
Post by: oren on April 17, 2020, 03:50:59 PM
Close up Worldview image of Sept 8th 2016
Thank you Niall.
And had that melting season not been cut short a day later due to the vagaries of weather, things might have been even more interesting. 2012 had the extent and area minimum to its name thanks to killing all the other seas within the Arctic Basin and to making a big dent in the CAB, but 2016 came much ahead in the hard-to-melt region around the pole.
Title: Re: The 2020 melting season
Post by: be cause on April 17, 2020, 04:20:13 PM
so that's 3 million years , 100,000 years , 6,000 years or nearly 4 years since the pole was a watery hole . Nice diversity in opinions .
This year the ice looks in better shape than many recently .. last year The Beaufort was a mess by now , Lincoln was heading out through Nares , and there was 200,000 fewer sq kms to melt . Last years movement from the ESS and Laptev toward Fram was more dramatic than this year though it paused in April while the latest forecasts suggest export will return with a vengeance in a few days . As Oren says this export is more damaging than a few hours above freezing .
  ^^ this said I do not doubt that this year will be amongst the worst for Arctic Sea Ice if not the worst in 4 years .. :) .. b.c.
  However the warmth over Siberia may well bring an early melt to it's northern shores in a few weeks ,
Title: Re: The 2020 melting season
Post by: Paul on April 17, 2020, 05:18:31 PM
Fram export will reduce but also polynyas are opening up in the CAB because of ice movement. From the weather forecast one can expect the polynyas won't refreeze but rather expand more

Nothing unusual in that though albeit you are correct that the holes won't refreeze because of the high temperatures. The holes will fill back in when the winds switch again and the models do indicate this will happen by day 4ish.

Suspect we may see holes appearing in the Laptev and ESS regions soon when the winds switch. The ESS a particular concern really but it will be interesting how it develops as nothing is stright forward in the Arctic.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on April 18, 2020, 02:23:15 AM
The ESS melting out before August is unlikely without extraordinary weather.

We have seen the ESS many years get battered and the ice sticks around.

Title: Re: The 2020 melting season
Post by: jdallen on April 18, 2020, 07:45:11 AM
Probably for the first time in about 3 million years, yes.

Not exactly JD:

http://GreatWhiteCon.info/2016/09/santa-extends-his-secret-summer-swimming-pool/
<snerk> 

Well, yes, but I was interpreting the question in context of BoE or near BoE giving us a complete meltout of say, everything within 100KM of the pole.

But, YMMV  ;)
Title: Re: The 2020 melting season
Post by: jdallen on April 18, 2020, 08:06:08 AM
The open water may extend to the Pole in Siberian side in September if such pattern will continue. The Laptev/ESS ice is already thin + early surface melting and quick land snow retreat in Siberia

If that happens, would it be the first time the pole melts?
Probably for the first time in about 3 million years, yes.

Possibly, although some have suggested that it may been as recently as 100,000 years ago.

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2013GL057188
https://www.independent.co.uk/environment/climate-change/arctic-could-become-ice-free-for-first-time-in-more-than-100000-years-claims-leading-scientist-a7065781.html

Others as recently as 6,000 years ago.

https://www.sciencedirect.com/science/article/pii/S0277379113004162?np=y
https://phys.org/news/2008-10-ice-arctic-ocean-years.html

I've been skeptical of assertions there have been more recent melt outs of the Arctic than during the late Pliocene warm period - which coincidentally corresponds to the last time atmospheric CO2 was this high.

I'm open to the possibility it's happened, but I haven't seen enough yet that's sufficiently definitive to convince me.

Others are welcome to post to that effect and I'll be happy to chew through them.
 
Title: Re: The 2020 melting season
Post by: oren on April 18, 2020, 09:59:18 AM
Just a gentle reminder, please continue discussions of the ASI thousands of years ago in a different thread.
Title: Re: The 2020 melting season
Post by: El Cid on April 18, 2020, 05:13:36 PM
I took a look at Bremen ice pictures for this date for many years and I have not seen so much light purple - maybe expect for 2007 April but then the weakness was in other zones. Now the Beaufort , the ESS and the Laptev seem very very weak. 2020, 2016 and 2007 shown.

I know it is totally weather dependent but I think we will see a record this year
Title: Re: The 2020 melting season
Post by: Freegrass on April 18, 2020, 05:48:14 PM
I took a look at Bremen ice pictures for this date for many years and I have not seen so much light purple - maybe expect for 2007 April but then the weakness was in other zones. Now the Beaufort , the ESS and the Laptev seem very very weak. 2020, 2016 and 2007 shown.

I know it is totally weather dependent but I think we will see a record this year (so true)
I don't see people using this website much, but I like it because IMHO the data matters less than the evolution of the data. Same data sets show trends, and this site's volume trend is showing a record minimum in volume.

I also like the animation this site provides.

http://polarportal.dk/en/sea-ice-and-icebergs/sea-ice-thickness-and-volume/ (http://polarportal.dk/en/sea-ice-and-icebergs/sea-ice-thickness-and-volume/)
Title: Re: The 2020 melting season
Post by: Milwen on April 18, 2020, 05:55:47 PM
https://worldview.earthdata.nasa.gov/?v=-171008,-991488,812032,-474880&p=arctic&i=1&l=Graticule,Reference_Labels(hidden),Reference_Features(hidden),Coastlines,VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor,MODIS_Terra_CorrectedReflectance_TrueColor (https://worldview.earthdata.nasa.gov/?v=-171008,-991488,812032,-474880&p=arctic&i=1&l=Graticule,Reference_Labels(hidden),Reference_Features(hidden),Coastlines,VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor,MODIS_Terra_CorrectedReflectance_TrueColor)

Look at this crack  :o
Title: Re: The 2020 melting season
Post by: Pavel on April 18, 2020, 07:14:40 PM
https://worldview.earthdata.nasa.gov/?v=-171008,-991488,812032,-474880&p=arctic&i=1&l=Graticule,Reference_Labels(hidden),Reference_Features(hidden),Coastlines,VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor,MODIS_Terra_CorrectedReflectance_TrueColor (https://worldview.earthdata.nasa.gov/?v=-171008,-991488,812032,-474880&p=arctic&i=1&l=Graticule,Reference_Labels(hidden),Reference_Features(hidden),Coastlines,VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor,MODIS_Terra_CorrectedReflectance_TrueColor)

Look at this crack  :o
Not unusual, in 2018 there was much bigger crack and open water in February. But what is unusual is the gray surface of Greenland this year. I've checked last 10 years, it was always bright white
Title: Re: The 2020 melting season
Post by: jdallen on April 18, 2020, 09:20:24 PM
https://worldview.earthdata.nasa.gov/?v=-171008,-991488,812032,-474880&p=arctic&i=1&l=Graticule,Reference_Labels(hidden),Reference_Features(hidden),Coastlines,VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor,MODIS_Terra_CorrectedReflectance_TrueColor (https://worldview.earthdata.nasa.gov/?v=-171008,-991488,812032,-474880&p=arctic&i=1&l=Graticule,Reference_Labels(hidden),Reference_Features(hidden),Coastlines,VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor,MODIS_Terra_CorrectedReflectance_TrueColor)

Look at this crack  :o

While I understand your alarm, *this* crack in particular isn't especially troublesome.  If you go back through the images, you'll see the ice in a similar state at this time most years over the last 15 or so.

Early on looking at Nares and Fram export I was very concerned about it, but while not trivial (at peak, 10-15,000km2 daily export of older ice will never be trivial...), I've seen over time it isn't as definitive in the way other seasonal dimensions are.

The crack is less important than the over-all integrity and thickness of the ice.  I'm less concerned about this region of the Arctic.  I think what will be happening in the other peripheral seas with early melting and melt ponding will be far more crucial to what outcome we have in September.
Title: Re: The 2020 melting season
Post by: Sublime_Rime on April 18, 2020, 09:21:16 PM
For more senior posters: To what extent to we expect this pulse of anomalies, averaging 4-5 C above normal, across the Eurasian side of the arctic over the next week to impact preconditioning (or pre-preconditioning)? Is it too early to begin melt-pond formation in earnest? If so, would melting snow atop the ice still reduce albedo, even if re-frozen?

I'd also like to begin tracking meltpond formation more closely in the weeks ahead. Does anyone know of a good resource for quantifying this?
Title: Re: The 2020 melting season
Post by: Freegrass on April 18, 2020, 09:51:59 PM
To what extent to we expect this pulse of 4-5C anomalies across the Eurasian side of the arctic over the next week to impact preconditioning (or pre-preconditioning)?
I'm sure more senior posters will correct me if I'm wrong, but I think the higher temperatures will only have an impact on the freezing of the ice. This "heatwave" basically ends the freezing season early.

Is there a mathematical formula that calculates the increase of ice volume with temperature?
How much possible volume do we lose with a 20°C temp anomaly? And how does that compare to fram export?
Title: Re: The 2020 melting season
Post by: Pavel on April 18, 2020, 11:47:03 PM
If the snow on the ice melts because of heat and moisture and refreezes after that, the albedo drops significantly. It may cause early meltponding, futher albedo drop and volume loss much more than Fram export
Title: Re: The 2020 melting season
Post by: Freegrass on April 19, 2020, 01:04:17 AM
If the snow on the ice melts because of heat and moisture and refreezes after that, the albedo drops significantly. It may cause early meltponding, futher albedo drop and volume loss much more than Fram export
That makes sense Pavel, but wouldn't snow blow over it again and cover those albedo weaknesses?
Title: Re: The 2020 melting season
Post by: Phoenix on April 19, 2020, 02:15:38 AM
For more senior posters: To what extent to we expect this pulse of anomalies, averaging 4-5 C above normal, across the Eurasian side of the arctic over the next week to impact preconditioning (or pre-preconditioning)? Is it too early to begin melt-pond formation in earnest? If so, would melting snow atop the ice still reduce albedo, even if re-frozen?

I'd also like to begin tracking meltpond formation more closely in the weeks ahead. Does anyone know of a good resource for quantifying this?

It might be more informative to share the absolute temperature chart along with the anomaly chart.  If we're at a time of year when the norm is -15C and we have a +5C anomaly, then the anomaly probably won't much a huge impact.
Title: Re: The 2020 melting season
Post by: oren on April 19, 2020, 07:58:16 AM
It's certainly too early to begin melt ponding in the Arctic Basin. And I can't recall any source that tracks melt ponding quantitatively, though looking at Worldview shows a telltale bluish color when melt ponding is widespread.
Title: Re: The 2020 melting season
Post by: wallen on April 19, 2020, 08:09:30 AM
It's certainly too early to begin melt ponding in the Arctic Basin. And I can't recall any source that tracks melt ponding quantitatively, though looking at Worldview shows a telltale bluish color when melt ponding is widespread.


With so much multi  directional cracking deep in the CAB, can this impact on the occurrence of melt
ponding ?
Title: Re: The 2020 melting season
Post by: jdallen on April 19, 2020, 09:29:34 AM
If the snow on the ice melts because of heat and moisture and refreezes after that, the albedo drops significantly. It may cause early meltponding, futher albedo drop and volume loss much more than Fram export
That makes sense Pavel, but wouldn't snow blow over it again and cover those albedo weaknesses?
Temperatures are not yet high enough for surface melt.  The primary effect here is to slow thickening of the ice in the region affected.

At this time of year, when there is melt, it tends to form sub surface (of the snow pack) melt ponds.  This does decrease albedo and increases  heat capture.

Looking at current temps under CR, it's still too cold.

Again looking at CR, the real action will be on the Laptev and Kara in a few days, where temperatures will be high enough for surface melt of the snowpack.  That may provide preconditioning for better melt when we get to May.

The real time to start watching these temperatures, albedo and cloud cover is in a couple of weeks.  That's the point at which insolation kicks up seriously and melt ponds will set the stage for what happens during the rest of the melt season.
Title: Re: The 2020 melting season
Post by: interstitial on April 19, 2020, 09:34:51 AM
with so much multi  directional cracking deep in the CAB, can this impact on the occurrence of melt
ponding ?
Mostly its easy to forget the scale. small objects you see may be a kilometer or more across. so not really
Title: Re: The 2020 melting season
Post by: Phoenix on April 19, 2020, 02:54:47 PM
April 10-16.

2019 (https://forum.arctic-sea-ice.net/index.php/topic,2591.msg195759.html#msg195759).

The kind of things one notices while observing their second melt season.

The crack which shows the beginning of the melt in the ESS. It runs from the islands which separate the ESS from the Laptev and meanders through the ESS until it connects with shore.

That initial crack is very similar shape as last year.  I could be wrong, but I'm going to guess it's a similar shape every year.  What is it about that particular piece of real estate that causes that crack to appear there first ?
Title: Re: The 2020 melting season
Post by: Niall Dollard on April 19, 2020, 05:21:27 PM

  What is it about that particular piece of real estate that causes that crack to appear there first ?

The ESS is a shallow sea. The fast ice stretches out several kms from the Russian coast and then separates from the main pack in the spring.

I havent checked back to see if the break off point is exactly same each year but probably something similar. This year it coincides quite close to the 25m depth line (isobath) looking at this bathymetry map. 
Title: Re: The 2020 melting season
Post by: Phoenix on April 19, 2020, 07:11:35 PM

  What is it about that particular piece of real estate that causes that crack to appear there first ?

The ESS is a shallow sea. The fast ice stretches out several kms from the Russian coast and then separates from the main pack in the spring.

I havent checked back to see if the break off point is exactly same each year but probably something similar. This year it coincides quite close to the 25m depth line (isobath) looking at this bathymetry map.

Thanks Niall for the detailed bathymetric chart. I see the correlation of the crack to the bathymetry.

I'm trying to get some sense of the process which creates the crack. In that regard, I'm wondering if the fast ice is frozen all the way down to the sea floor? It's shallow there and a frozen continent in winter might have the means to freeze the water beneath.
Title: Re: The 2020 melting season
Post by: blumenkraft on April 19, 2020, 07:50:36 PM
Without commentary, the Sunday movies.

7-day hindsight mean temperature anomalies
& DMI 80°N 2m Temperature
Title: Re: The 2020 melting season
Post by: blumenkraft on April 19, 2020, 07:51:21 PM
Fram export/import via SAR
Title: Re: The 2020 melting season
Post by: blumenkraft on April 19, 2020, 07:51:57 PM
Ice drift map.
Title: Re: The 2020 melting season
Post by: blumenkraft on April 19, 2020, 07:52:29 PM
Ozone.
Title: Re: The 2020 melting season
Post by: VeliAlbertKallio on April 19, 2020, 07:55:44 PM
This is just so terrible I started to cry, I knew Professor Sir John Houghton. He just passed away due to UK's terrible coronavirus epidemic.

 :'( FAMOUS BRITISH SCIENTIST AND IPCC 2007 NOBEL PRIZE TAKER DIES OF CORONAVIRUS

https://www.bbc.co.uk/news/uk-wales-52325374  :'( :'( :'( :'( :'( :'( :'( :'( :'( :'( :'(

Title: Re: The 2020 melting season
Post by: oren on April 19, 2020, 08:48:31 PM
Ozone.
I prefer that this regular update be posted in a new thread, as it does not affect the current melting season as far as I can tell.
Title: Re: The 2020 melting season
Post by: Niall Dollard on April 19, 2020, 09:34:05 PM


I'm trying to get some sense of the process which creates the crack. In that regard, I'm wondering if the fast ice is frozen all the way down to the sea floor? It's shallow there and a frozen continent in winter might have the means to freeze the water beneath.

It's not the ESS, but there is a nice schematic of the break up process over at Barrow (Utqiagvik) Alaska on this link.

https://seaice.alaska.edu/gi/observatories/barrow_breakup/

The fast ice there is supported by grounded pressure ridges. But some years the pressure ridges can be unreliable. I imagine it is something similar in ESS, only extended out further ?

Title: Re: The 2020 melting season
Post by: Niall Dollard on April 19, 2020, 09:53:36 PM
This is just so terrible I started to cry, I knew Professor Sir John Houghton. He just passed away due to UK's terrible coronavirus epidemic.

 :'( FAMOUS BRITISH SCIENTIST AND IPCC 2007 NOBEL PRIZE TAKER DIES OF CORONAVIRUS

https://www.bbc.co.uk/news/uk-wales-52325374  :'( :'( :'( :'( :'( :'( :'( :'( :'( :'( :'(

Yes. It is sad news.

A wonderful tribute to him from his granddaughter on twitter here:

https://twitter.com/hannahmmalcolm/status/1250778555505655808
Title: Re: The 2020 melting season
Post by: Phoenix on April 19, 2020, 10:13:58 PM


I'm trying to get some sense of the process which creates the crack. In that regard, I'm wondering if the fast ice is frozen all the way down to the sea floor? It's shallow there and a frozen continent in winter might have the means to freeze the water beneath.

It's not the ESS, but there is a nice schematic of the break up process over at Barrow (Utqiagvik) Alaska on this link.

https://seaice.alaska.edu/gi/observatories/barrow_breakup/

The fast ice there is supported by grounded pressure ridges. But some years the pressure ridges can be unreliable. I imagine it is something similar in ESS, only extended out further ?

That's a great link Niall, thank you !!

From the image it appears that the pressure ridge is a barrier to incoming warm current. I confess that I have zero clue as to why an ice ridge would form instead of freezing all the way to the coast. The image shows the ridge extended away from the coast. The area between the ridge and the coast is depicted as surface fast ice over water. Why that section wouldn't freeze all the way to the ocean floor is a mystery.

Anybody? 
Title: Re: The 2020 melting season
Post by: oren on April 19, 2020, 10:42:47 PM
Ice growth rates are not high enough to freeze all the way to the bottom. During a season new ice can reach maybe 2m, the thicker the ice the slower the growth. But ice floes being stood sideways due to pressure from the pack (and counterforce from the shore) can reach the bottom.
Title: Re: The 2020 melting season
Post by: Glen Koehler on April 20, 2020, 12:12:13 AM
And I can't recall any source that tracks melt ponding quantitatively, though looking at Worldview shows a telltale bluish color when melt ponding is widespread.
  Neven discussed visual estimates of melt pond prevalence on the ASI blog a few years ago.  It seems like a tool was being developed but never really arrived.

This from: https://neven1.typepad.com/blog/2014/04/more-on-melt-ponds.html#more (https://neven1.typepad.com/blog/2014/04/more-on-melt-ponds.html#more)
-------------------
Neven asks - "How difficult is it to create near real-time melt pond cover fraction data that can be compared to other melting seasons in the 2007-2013 period?"

We may not be that far away. One of the papers currently in discussion at The Cryosphere Discuss is Sea ice melt pond fraction estimation from dual-polarisation C-band SAR – Part 1: In situ observations (R. K. Scharien, J. Landy, and D. G. Barber).
http://www.the-cryosphere-discuss.net/8/805/2014/tcd-8-805-2014.pdf (http://www.the-cryosphere-discuss.net/8/805/2014/tcd-8-805-2014.pdf)
Posted by: Kevin O'Neill | April 27, 2014 at 01:09
-------------------

And this
https://neven1.typepad.com/blog/2016/07/2016-melting-momentum-part-3.html?cid=6a0133f03a1e37970b01b7c87b7ac1970b#comment-6a0133f03a1e37970b01b7c87b7ac1970b (https://neven1.typepad.com/blog/2016/07/2016-melting-momentum-part-3.html?cid=6a0133f03a1e37970b01b7c87b7ac1970b#comment-6a0133f03a1e37970b01b7c87b7ac1970b)
Title: Re: The 2020 melting season
Post by: Phoenix on April 20, 2020, 12:13:08 AM
Ice growth rates are not high enough to freeze all the way to the bottom. During a season new ice can reach maybe 2m, the thicker the ice the slower the growth. But ice floes being stood sideways due to pressure from the pack (and counterforce from the shore) can reach the bottom.

So, what are those ridges in the image that Niall shared ? It looks like a vertical wall of ice from  sea floor to surface.  Is that image misleading ?

Big picture, I'm still trying to understand why the ice begins to melt in that particular place. Any enlightenment appreciated.
Title: Re: The 2020 melting season
Post by: Niall Dollard on April 20, 2020, 01:22:00 AM
Ice ridges can stick up and down.

Have a look at these recent sonar scans from the MOSAiC expedition.

https://twitter.com/CKatlein/status/1246136156594622465

Re Melt Ponds. NOAA's Physical Science Lab (formerly the ESRL) has a forecast section on melt ponds (under the "Coupled" Menu) As it happens it's showing some activity at present in the northern Kara.

https://psl.noaa.gov/forecasts/seaice/
Title: Re: The 2020 melting season
Post by: oren on April 20, 2020, 02:39:10 AM
It's useful to read the Wikipedia entry on Pressure Ridges, and another entry about Stamukha.
https://en.wikipedia.org/wiki/Pressure_ridge_(ice) (https://en.wikipedia.org/wiki/Pressure_ridge_(ice))
https://en.wikipedia.org/wiki/Stamukha (https://en.wikipedia.org/wiki/Stamukha)

Quote
Pressure ridges are the thickest sea ice features and account for about one-half of the total sea ice volume. Stamukhi are pressure ridges that are grounded and that result from the interaction between fast ice and the drifting pack ice.

Quote
One of the largest pressure ridges on record had a sail extending 12 metres (39 ft) above the water surface, and a keel depth of 45 metres (148 ft). The total thickness for a multiyear ridge was reported to be 40 metres (130 ft). On average, total thickness ranges between 5 metres (16 ft) and 30 metres (98 ft), with a mean sail height that remains below 2 metres (6.6 ft).
Title: Re: The 2020 melting season
Post by: Phoenix on April 20, 2020, 03:09:05 AM
It's useful to read the Wikipedia entry on Pressure Ridges, and another entry about Stamukha.
https://en.wikipedia.org/wiki/Pressure_ridge_(ice) (https://en.wikipedia.org/wiki/Pressure_ridge_(ice))
https://en.wikipedia.org/wiki/Stamukha (https://en.wikipedia.org/wiki/Stamukha)

Quote
Pressure ridges are the thickest sea ice features and account for about one-half of the total sea ice volume. Stamukhi are pressure ridges that are grounded and that result from the interaction between fast ice and the drifting pack ice.

Quote
One of the largest pressure ridges on record had a sail extending 12 metres (39 ft) above the water surface, and a keel depth of 45 metres (148 ft). The total thickness for a multiyear ridge was reported to be 40 metres (130 ft). On average, total thickness ranges between 5 metres (16 ft) and 30 metres (98 ft), with a mean sail height that remains below 2 metres (6.6 ft).

Interesting. stamukha (the grounded version of ridges) are most often found at depth of 20m which corresponds to Niall's depth chart above. Additionally, stamukha is a Russian word and the crack in question is found on the Russian coast.

So far, the shoe fits !!

So, a good working theory is that the repeating initial crack in the ESS is found at the 20m depth stamukha line.

If I were to imagine how the works in total, you have incoming warm Atlantic water entering the Arctic and Coriolis forces have it hugging the Siberian coast until it hits the stamukha wall and is forced toward the surface which is just a few meters above. Sound reasonable ?

Thanks for the wiki link Oren.

Edit: Alternative / complementary view is that the opening of this crack is also influenced heavily by wind. Looking at Aluminum's most recent post (#339) it seems like the crack was pretty wide a few days ago and then shut down with a change in wind direction.
Title: Re: The 2020 melting season
Post by: John_The_Elder on April 20, 2020, 03:10:44 AM
To what extent to we expect this pulse of 4-5C anomalies across the Eurasian side of the arctic over the next week to impact preconditioning (or pre-preconditioning)?
I'm sure more senior posters will correct me if I'm wrong, but I think the higher temperatures will only have an impact on the freezing of the ice. This "heatwave" basically ends the freezing season early.

Is there a mathematical formula that calculates the increase of ice volume with temperature?
How much possible volume do we lose with a 20°C temp anomaly? And how does that compare to fram export?

There is a formula that calculates the increase of thickness with temperature. Found at https://sites.google.com/site/cryospherecomputing/fdd.

Volume should reach its peak any day now if has not already.
Title: Re: The 2020 melting season
Post by: oren on April 20, 2020, 04:39:56 AM
Which reminds me of the very useful graph of FDDs by Nico Sun. This year was much better than the last few years, as the Arctic was colder during the winter, and volume is not running at a near-record level. Hopefully this will pay off with higher resistance to melting.
Title: Re: The 2020 melting season
Post by: guygee on April 20, 2020, 08:23:52 AM
Ozone.
I prefer that this regular update be posted in a new thread, as it does not affect the current melting season as far as I can tell.
Oren - I see you are listed as Moderator and thus you decide "what goes where". However, consider that the ozone level animations are a kind of proxy for the polar stratospheric circulation, also that the stratospheric ozone in the polar vortex will increase rather dramatically at the onset of a Sudden Stratospheric Warming (SSW). Such events do have relevance in the melting season. For a simple example please see:

]https://ozonewatch.gsfc.nasa.gov/facts/warming_NH.html (https://ozonewatch.gsfc.nasa.gov/facts/warming_NH.html)

Actually it is a bit more complicated than the simple view expressed above, see:

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/jgrd.50651 (https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/jgrd.50651)
https://arxiv.org/abs/1807.11750 (https://arxiv.org/abs/1807.11750)

Thus, I think that the ozone measurement animations are relevant to melting, at least in the early part of the melting season.
Title: Re: The 2020 melting season
Post by: Aluminium on April 20, 2020, 10:35:19 AM
April 14-19.

2019 (https://forum.arctic-sea-ice.net/index.php/topic,2591.msg196515.html#msg196515).
Title: Re: The 2020 melting season
Post by: oren on April 20, 2020, 10:53:59 AM
Thanks for the explanation guygee. Let the ozone remain.
Title: Re: The 2020 melting season
Post by: Freegrass on April 20, 2020, 01:48:20 PM
Five day forecast Wind @ Surface not looking good for the Barents sea ice.
Title: Re: The 2020 melting season
Post by: Glen Koehler on April 20, 2020, 02:36:20 PM
There is a formula that calculates the increase of thickness with temperature. Found at https://sites.google.com/site/cryospherecomputing/fdd.
1) I'm surprised that a formula based solely on temperature would be accurate. 
The chart from Thorndike 1975 shows that the thicker the ice the slower it grows. 
See https://forum.arctic-sea-ice.net/index.php/topic,778.msg32166.html#msg32166 (https://forum.arctic-sea-ice.net/index.php/topic,778.msg32166.html#msg32166)

     The Crysopshere Computing background page for the formula does not address the thickness effect specifically, but it does say that the formula is just a rough estimate that ignores other factors:
     "The ice thickness increases at a rate roughly proportional to the square root of the cumulative FDD. Formulas such as this are empirical, meaning they are calculated only with observed data, so they really are simplifications of the ice growth processes. The formulas assume that the ice growth occurs in calm water and is reasonably consistent, and they do not take into account sea ice motion, snow cover, and other surface conditions."

     IMO that explanation also implies that the formula is for the initial phase of ice formation, i.e. starting from no ice (= 0 thickness). 


2) Is there a formula, crude or otherwise, for the decrease in ice thickness according to starting thickness and/or temperature? 

     A while back on the "When will the Arctic Go Ice Free?" thread I proposed reversing the Thorndike "thickness effect on subsequent ice thickening" curve to estimate the rate at which thinner ice melts faster than thicker ice.  But that idea was shot down as incorrect.  Apparently, the effect of thickness on more freezing is not reversible to estimate the effect of thickness on melting rate. 

     A query and a minimal search for such a formula found nothing.  It seems like an easy physical experiment to do, and an important clue to how ASI decline will evolve as the average Thickness continues to decline along with Extent and Volume.  Somebody must have calculated that effect.
Title: Re: The 2020 melting season
Post by: Freegrass on April 20, 2020, 03:39:56 PM
1) I'm surprised that a formula based solely on temperature would be accurate. 
The chart from Thorndike 1975 shows that the thicker the ice the slower it grows. 
See https://forum.arctic-sea-ice.net/index.php/topic,778.msg32166.html#msg32166 (https://forum.arctic-sea-ice.net/index.php/topic,778.msg32166.html#msg32166)
Thank you Glen! This link you posted provided an answer to my question how much possible volume we would lose with a 20°C temp anomaly. Probably not much, except for places with thin ice.

Quote
Say you increased the length of the freeze season, you'd get only small increase in thermodynamic thickening because by 1.5m and above the rate of ice growth is small. This is because as the ice thickens it better insulates ocean (warmer) from the colder atmosphere. So for anything over 1.5m thickness, shorten the freeze season even by as much as a month and you get very little impact on thermodynamic thickness
Title: Re: The 2020 melting season
Post by: paolo on April 20, 2020, 03:53:55 PM
Glen Koehler,
I think that the formula given by John_The_Elder in the previous post: "Thickness (cm) = 1.33 * FDD (°C)0.58", is relative to a starting situation without ice. If at the beginning there is already an ice thickness to use the formula you have to add to the FDD the value that gives the thickness already present (and the influence of the thickness in the formula is given by the exponent 0.58).
Title: Re: The 2020 melting season
Post by: gerontocrat on April 20, 2020, 05:20:46 PM
Glen Koehler,
I think that the formula given by John_The_Elder in the previous post: "Thickness (cm) = 1.33 * FDD (°C)0.58", is relative to a starting situation without ice. If at the beginning there is already an ice thickness to use the formula you have to add to the FDD the value that gives the thickness already present (and the influence of the thickness in the formula is given by the exponent 0.58).
Nico Sun quotes this formula in his webpage for FDD   https://cryospherecomputing.tk/index.html

The source quoted is  "Lebedev - 1938". One wonders what research / testing has been on this formula since 1938.
Title: Re: The 2020 melting season
Post by: oren on April 20, 2020, 05:39:06 PM
Here's a link to a Chris Reynolds discussion on ice growth calculations, and another to a post in his "Slow Transition" thread about Lebedev and Billelo and related issues.
http://dosbat.blogspot.com/2015/01/the-simplest-model-of-sea-ice-growth.html (http://dosbat.blogspot.com/2015/01/the-simplest-model-of-sea-ice-growth.html)
https://forum.arctic-sea-ice.net/index.php/topic,933.msg58049.html#msg58049 (https://forum.arctic-sea-ice.net/index.php/topic,933.msg58049.html#msg58049)

I would ask that further discussion of this very important issue continue in a different existing thread, or start a new one if needed.
Make a search for Lebedev and Billelo to help in locating a suitable venue.
Title: Re: The 2020 melting season
Post by: RoxTheGeologist on April 20, 2020, 09:39:52 PM

Also:

When insolation < emission, snow is bad as it insulates and prevents heat loss.
When insolation > emission, snow is good as it prevents the ice heating up.

Title: Re: The 2020 melting season
Post by: gerontocrat on April 20, 2020, 10:54:16 PM
They tell me that the highly +ve Arctic Oscillation has had much to do with the strong Polar Vortex and the resulting high Arctic Sea Ice maximum this year, especially almost 100% concentration in the central seas..

So I thought I had better have a look at the forecasts on....

https://www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/ao.shtml

There is a GFS and an Ensemble forecast, 7, 10, & 14 day forecasts. Both products suggest the +ve AO isn't over yet. If so, this could imply continuing cold in the central seas and warmth in the periphery?

Also, both sets of forecasts consistently under-estimated the strength of the +ve index from January to date.
Also, the 7 day forecast is close to reality. The 14 day forecast looks pretty useless to me.

ps:- It is a really good website - even a quick wander around in it taught me quite a lot.
Title: Re: The 2020 melting season
Post by: VeliAlbertKallio on April 21, 2020, 12:27:39 AM
I have more satellite data that I have been hoping to present this season but due to my system breakdown and cost of repairs US$1,500, I have not been able to access the images I would have wished to put out this season on some debates. (Difficulty is that the firmware reader of data is incompatible with all PC and MacIntosh so finding people and spares is very hard for me to fix it.)
I can on this debate offer you a few images that I have put on my Curriculum Vitae that can be downloaded from Academia.edu. They are not of best resolutions, nor all of the images available that are highlighting this matter, but every bit will, nevertheless, help.

It is costly to produce images which provide optic side scans and repeat scans (multiplexing) of sea ice as this involves flying satellite constellations repeatedly in different angles and one after another. It is getting ever easier and one day all this is probably routine. Also a Fournier triangulation is avoided to spot visually a target such as a moving warship and to identify which ship or submarine has surfaced from the Arctic sea ice. It is tedious exercise to keep tabs (particularly on nuclear submarines as they are small and can disappear quickly back into ice).

For our discussion here we are interested about the formation of the leads, why and where they form:

Multiplex imaging with satellite cluster produces images of entire Arctic Ocean cloud-free during sunlight season, including the infrared and UV-scanners that identify sources or ships' heat or electric lights, whatever. On CV page 10 you can see how the continuous breakwater pulse propagates within the Arctic Ocean and weakens the sea ice from the estuary onwards. (The large image on the top.) Typically ultimate "C", penultimate "B", and antepenultimate "A" ice floes form from the Russian coast running their weakened seams perpendicularly to Canada where the ultimate "C" typically hits at the Western Last Sea Ice Area (Western - LIA) where the turning process causes opposite stress point, thus segregating the ultimate "C" and penultimate "B". There are two of these, but only one C/B is shown on my CV, both of them would be interest to this discussion.

There are couple other processes on the Arctic Ocean:

Page 8 The antepenultimate "A" facing the Atlantic runs on its own with the alternating zebra patterns of green and white on this image (result of breakwater waves or cells rolling on shallow sea).

The density differentials form the colours here as the river water from Russia moves along and rolls a bit like Swiss roll on its way to deep water near Fram Strait. The high density water is white as sea surface is lower than the ocean median ice surface (the median lines are highlighted on image for clarity), the low density river water is green due to it representing higher than the ocean median ice surface (due to its being less saline, it needs higher water column than saline water to keep ocean surface at equilibrium pressure).

The white colour forms over the dense water where ocean surface is lower than median and fills with drift snow. The green colour forms on the crest that is higher and without the drift snow that accumulates on troughs. The snow accumulation further amplifies the effect anchoring even more snow over the dense, saline rollers.

Because of this constant rolling of Swiss rolls between the ocean floor and its surface (sea ice), there is an overall current which has higher gravity potential and faster forward movement on surface, this then marks the boundary between antepenultimate "A", and penultimate "B" as the B flows slower than A.

These things have also changed over the years as ice in overall has pulverised and not been forming uniform films, but overall show the effect of North Asian rivers discharging onto the Arctic Ocean and forming weak points by supply of warmer water and its mixing and dragging heat out from warmer waters beneath - then maintaining a thinner ice along a narrow channel which presses against Canada (Western Last Sea Ice Area, by splitting the sea ice C/B and B/A, with B/A junction also running at different speed.

The differential movement on p. 8 is shown by 12 perpendicular secondary cracks (highlighted) on the main B/A crossing from Komsomoletski Island to Ellesmere Island.

Page 9 focuses on vortices or breakwater cells that fall into the deep channel, warm up aggressively and surface like cumulus cloud with the centre of pancake elevated with edges bending down and below median and filled by snow. These curving sea ice "spaghetti" edge formations are rare in comparison of the rectangular edge formations caused by breaking ice and re-freezing ice.

The rest of my Curriculum Vitae outside pages 8, 9, 10 are irrelevant to this forum.
https://www.academia.edu/5859691/Curriculum_Vitae_for_Exploration_and_Research

It's useful to read the Wikipedia entry on Pressure Ridges, and another entry about Stamukha.
https://en.wikipedia.org/wiki/Pressure_ridge_(ice) (https://en.wikipedia.org/wiki/Pressure_ridge_(ice))
https://en.wikipedia.org/wiki/Stamukha (https://en.wikipedia.org/wiki/Stamukha)

Quote
Pressure ridges are the thickest sea ice features and account for about one-half of the total sea ice volume. Stamukhi are pressure ridges that are grounded and that result from the interaction between fast ice and the drifting pack ice.

Quote
One of the largest pressure ridges on record had a sail extending 12 metres (39 ft) above the water surface, and a keel depth of 45 metres (148 ft). The total thickness for a multiyear ridge was reported to be 40 metres (130 ft). On average, total thickness ranges between 5 metres (16 ft) and 30 metres (98 ft), with a mean sail height that remains below 2 metres (6.6 ft).

Interesting. stamukha (the grounded version of ridges) are most often found at depth of 20m which corresponds to Niall's depth chart above. Additionally, stamukha is a Russian word and the crack in question is found on the Russian coast.

So far, the shoe fits !!

So, a good working theory is that the repeating initial crack in the ESS is found at the 20m depth stamukha line.

If I were to imagine how the works in total, you have incoming warm Atlantic water entering the Arctic and Coriolis forces have it hugging the Siberian coast until it hits the stamukha wall and is forced toward the surface which is just a few meters above. Sound reasonable ?

Thanks for the wiki link Oren.

Edit: Alternative / complementary view is that the opening of this crack is also influenced heavily by wind. Looking at Aluminum's most recent post (#339) it seems like the crack was pretty wide a few days ago and then shut down with a change in wind direction.
Title: Re: The 2020 melting season
Post by: Jim Hunt on April 21, 2020, 12:44:34 AM
Volume is not running at a near-record level. Hopefully this will pay off with higher resistance to melting.

That rather depends upon which volume metric you choose to look at:

http://GreatWhiteCon.info/2020/03/facts-about-the-arctic-in-april-2020/#Apr-19
Title: Re: The 2020 melting season
Post by: Niall Dollard on April 21, 2020, 12:47:34 AM
Five day forecast Wind @ Surface not looking good for the Barents sea ice.

In what sense ?

Temperatures will be low with strong north and northwest winds. We will likely see the ice edge extending south.

The ice will of course melt as it pushes further south towards Norway. But in the meantime I expect we will see Barents extent and area increase a bit.

Title: Re: The 2020 melting season
Post by: Freegrass on April 21, 2020, 01:56:41 AM
Five day forecast Wind @ Surface not looking good for the Barents sea ice.

In what sense ?

Temperatures will be low with strong north and northwest winds. We will likely see the ice edge extending south.

The ice will of course melt as it pushes further south towards Norway. But in the meantime I expect we will see Barents extent and area increase a bit.
I agree, but it's not really that cold, and as you say, a lot of that ice will be pushed into warm water, where it will melt quickly.

The other problem I see are the large polynyas that have opened up. The wind will be able to create waves there that are destructive for the ice, no?

Has anyone noticed the missing ice on the Greenland coast?
Title: Re: The 2020 melting season
Post by: Niall Dollard on April 21, 2020, 01:42:28 PM
Yes FG, holes in the ice are often formed in the lee of islands of Franz Josef Land and Svalbard.

So when winds were southerly for a time recently holes appeared to the north of the islands as the wind pushed the ice away.

However if the forecasts follow through with north or northwest winds these holes will likely close back in with new ones possible on the lee (southern side) of the islands.
Title: Re: The 2020 melting season
Post by: Aluminium on April 21, 2020, 04:10:43 PM
From last years I have got this recipe for perfect melting.

1. High temperature at 850 hPa. Snow and ice are initially resistant to visible light but vulnerable to infrared radiation. Difference between 280 K and 260 K is 90 W/m2 according to the Stefan–Boltzmann law.
2. High total precipitable water. Greenhouse gases are required for infrared interaction with atmosphere. In addition, water vapor contains a lot of energy. Carbon dioxide takes a part here.
3. High declination of the Sun and clear sky. After some melting, ice is getting darker.

The New Siberian Islands is getting something like it at this moment, though it's a weak version. Dew point reached -3.5°C at 3:00 UTC (74.67 N 138.90 E).
Title: Re: The 2020 melting season
Post by: Freegrass on April 21, 2020, 04:46:03 PM
After some melting, ice is getting darker.
If that melting occurs early in the season, wouldn't snow blowing over it again cover those spots? Or does that lowered albedo last through the season?
Title: Re: The 2020 melting season
Post by: Aluminium on April 21, 2020, 06:14:49 PM
If that melting occurs early in the season, wouldn't snow blowing over it again cover those spots?
I think, yes, easily. However, some effects may last for a long time. Thinner snow cover and early access to warmth are not good for ice. Cold ice have margin of safety. You need to heat up it before melting.
Title: Re: The 2020 melting season
Post by: Freegrass on April 21, 2020, 07:17:04 PM
If that melting occurs early in the season, wouldn't snow blowing over it again cover those spots?
I think, yes, easily. However, some effects may last for a long time. Thinner snow cover and early access to warmth are not good for ice. Cold ice have margin of safety. You need to heat up it before melting.
When snow melts, it becomes more compact, and then refreezes. Air is taken out. So the insulating factor of the snow goes down, right? But you also get a harder icy surface that's more difficult to melt, no?


Edit: If you decrease the insulating factor of snow through short-term melting, wouldn't that help the ice to grow thicker when temperatures drop again?

I guess this is all basic ice physics?
Title: Re: The 2020 melting season
Post by: Aluminium on April 21, 2020, 07:55:54 PM
I agree with all.

My interest is effect of current event. Will it be something notable?
Title: Re: The 2020 melting season
Post by: Paul on April 21, 2020, 09:55:38 PM
I agree with all.

My interest is effect of current event. Will it be something notable?

What current event? If you mean the current above average temps across the basin then I would say it will have little to no affect on what may happen in the future as temperatures won't be constantly at or above zero for any length of time. Also the models are showing the AO turning more positive so the temperatures will head downwards again in anycase.

This April has been totally different to the last few April's in that high pressure has been largely absent across the basin. In all honesty, I think high pressure is probably better for the ice than low pressure as the ice is getting compacted and the heat still escapes at night. We shall see what persistent low pressure will have on weather patterns as we head into May.
Title: Re: The 2020 melting season
Post by: Freegrass on April 21, 2020, 11:17:26 PM
My interest is effect of current event. Will it be something notable?

Current effects will always be balanced by further events...
Although I do think that this will be a "special" year, with extraordinary circumstances...
Title: Re: The 2020 melting season
Post by: Frivolousz21 on April 22, 2020, 12:43:18 PM
Until we see a jump towards record snow cover loss in May on land and in June on the ice we have no chance for a new record low. 

And snow cover loss has stalled out.

Guess what...

Ice loss has stalled out.

I'm starting to think maybe the permafrost helps slow snow melt in high spring sun?

I don't know...

Thoughts???
Title: Re: The 2020 melting season
Post by: Shared Humanity on April 22, 2020, 02:38:53 PM
Until we see a jump towards record snow cover loss in May on land and in June on the ice we have no chance for a new record low. 

And snow cover loss has stalled out.

Guess what...

Ice loss has stalled out.

I'm starting to think maybe the permafrost helps slow snow melt in high spring sun?

I don't know...

Thoughts???

I think that heavy snow in the high latitudes is a developing new normal for the NH and this needs to be watched closely.

https://www.ccin.ca/index.php/ccw/snow/current
Title: Re: The 2020 melting season
Post by: dnem on April 22, 2020, 03:46:05 PM
I think that heavy snow in the high latitudes is a developing new normal for the NH and this needs to be watched closely.

BBR, is that you?!
Title: Re: The 2020 melting season
Post by: Aluminium on April 22, 2020, 03:58:03 PM
Kotelny Island reached +1.2°С today. Previous record of April was +0.3°С in 1967.
Title: Re: The 2020 melting season
Post by: be cause on April 22, 2020, 04:18:00 PM
[quote author=dnem link=topic=3017.msg261090#msg261090 date=1587563165

BBR, is that you?




 sadly not .. SH has been @ for a few years .. bbr , absent for a few months .. :)

 the ongoing assault on Kara is interesting .. very mobile ice and a 960 mb low passing over .. b.c.



Title: Re: The 2020 melting season
Post by: blumenkraft on April 22, 2020, 04:32:39 PM
absent for a few months

Absent due to ban.
Title: Re: The 2020 melting season
Post by: jdallen on April 22, 2020, 06:38:27 PM
Until we see a jump towards record snow cover loss in May on land and in June on the ice we have no chance for a new record low. 

And snow cover loss has stalled out.

Guess what...

Ice loss has stalled out.

I'm starting to think maybe the permafrost helps slow snow melt in high spring sun?

I don't know...

Thoughts???
Less permafrost I think and more a negative feedback from increased moisture being carried to high latitudes in winter.

While we have a lack of coverage in some areas, there are lots of places where the snow pack is 20cm or more thicker than has been typical.

I'm looking to see if this translates into uneven distribution of melt on the ice, theory here being where there is less continental snow pack, peripheral ice gets attacked earlier, and the reverse. 

It also *will* translate into more spring melt, so I'm interested to watch drainage basins where there is a higher snow load to see what happens in the ESS, Laptev & Kara seas.
Title: Re: The 2020 melting season
Post by: El Cid on April 22, 2020, 09:24:45 PM
I think that heavy snow in the high latitudes is a developing new normal for the NH and this needs to be watched closely.

BBR, is that you?!

 :)
I wanted to ask the same!!!
Title: Re: The 2020 melting season
Post by: Shared Humanity on April 22, 2020, 11:55:02 PM
I think that heavy snow in the high latitudes is a developing new normal for the NH and this needs to be watched closely.

BBR, is that you?!

 :)
I wanted to ask the same!!!

I kind of miss his impending ice age comments.  ;)
Title: Re: The 2020 melting season
Post by: be cause on April 23, 2020, 12:52:00 AM
  .. even his absence causes an avalanche ! ^^^  :) .. b.c.
Title: Re: The 2020 melting season
Post by: bbr2315 on April 23, 2020, 02:51:26 AM
I have been summoned!

<Welcome back but note things have changed and moderation will be swift. Impending ice age and racism shenanigans will be summarily removed. O>
Title: Re: The 2020 melting season
Post by: Wildcatter on April 23, 2020, 07:06:52 AM
Hmmmm. I'm seeing a ton of snow melt across Eurasia with that low pressure system advecting a bunch of heat, possibly in the running for near-record low in Eurasia, by the end of April. Maybe I'm looking at the wrong Arctic.  ;D  NA snow has started its melt, enough to advect some heat + winds over the Hudson in about 4 days. It's a hot year.

Baffin volume record low for April 15 (thanks Wipneus and Oren!), will also get additional heat + and some winds soon.

Also, just for reference, it's still April 22. The first screenshot I attached is Bremen for April 15, as a lot of additional volume this year was stored in the Barents, Kara, and Greenland Seas, per Wipneus an Oren's work in the volume thread. The second screenshot, will be Bremen from April 30, 2019, to provide a frame of reference. And the third, is from today's Bremen - April 22, 2020.

As a digestif, over the next 4-5 days, there is a cyclone forming that will move over the Kara tomorrow, progressing over Severnaya the next day, with tail winds from the low pressure system over Laptev coast. More winds pushing into Barents, some CAB, export in some form or another. Pack over there has seen better days.
Low pressure system moving across Eurasia helping snow melt will come to the Laptev and ESS, New Siberian Islands shortly after. If the forecast works out. Mini cyclone system predicted to form, could be interesting with the volume numbers. Wind effect on coasts could be pretty significant for April.

You may be interested in the Nullschool after seeing the attached images, so here you go.
https://earth.nullschool.net/#current/wind/surface/level/overlay=temp/orthographic=-85.68,81.75,450/loc=175.423,74.073 (https://earth.nullschool.net/#current/wind/surface/level/overlay=temp/orthographic=-85.68,81.75,450/loc=175.423,74.073)

Let the games begin.
Title: Re: The 2020 melting season
Post by: Aluminium on April 23, 2020, 09:28:26 AM
April 17-22.

2019 (https://forum.arctic-sea-ice.net/index.php/topic,2591.msg196515.html#msg196515).
Title: Re: The 2020 melting season
Post by: Pavel on April 23, 2020, 10:25:50 AM
Western Siberia today 23.04 and the same day of year in 2019
Title: Re: The 2020 melting season
Post by: El Cid on April 23, 2020, 10:31:37 AM
The way I see it is that a lot of old ice was exported to the Barents last year and that is missing from the "core" of the Arctic. If this ice exported goes poof fast then there will be trouble as these were the "reserves" against General Summer. No more "experienced troops" left in the Arctic
Title: Re: The 2020 melting season
Post by: Freegrass on April 23, 2020, 11:17:11 AM
Western Siberia today 23.04 and the same day of year in 2019
I can also see a lot of smoke already getting caught up in that southerly that's blowing into the arctic.
Title: Re: The 2020 melting season
Post by: interstitial on April 23, 2020, 12:12:38 PM
latest DMI thickness map
Title: Re: The 2020 melting season
Post by: Paul on April 23, 2020, 12:44:23 PM
The comments on the volume thread really does tell its own story regarding the ice on the Russian side of the basin. The ESS ice really does look in trouble and an early melt is highly possible, similar to what we saw in 2017. I notice on today's worldview update another little bit of fast ice is detatching itself and there is hardly any fast ice there at all this year. If we see any heatwaves like June last year then I can't see it lasting.

The better news is the Beaufort sea ice looks more resilient than last year and there is no real signs of the Beaufort high developing so unless that changes during May I'll be surprised if we see the large amount of open water developing as we did last year.
Title: Re: The 2020 melting season
Post by: Freegrass on April 23, 2020, 01:21:43 PM
Five day Forecast Wind + Temp @ Surface
Title: Re: The 2020 melting season
Post by: Freegrass on April 23, 2020, 03:21:28 PM
latest DMI thickness map
Do you see the blue in the Chukchi sea? I think that's hot pacific water that will be penetrating deep into the CAP CAB this year. As I wrote here before, I believe that the slowdown of the AMOC is causing more pacific water to enter the arctic ocean. That water is also hotter now, so you get a double whammy. And strike three is this missing arm of thick ice that should be protecting the CAB. But that arm is also missing this season.

Increases in the Pacific inflow to the Arctic from 1990 to 2015, and insights into seasonal trends and driving mechanisms from year-round Bering Strait mooring data.
http://psc.apl.washington.edu/HLD/Bstrait/BeringStraitSeasonalInterannualChange2017.html (http://psc.apl.washington.edu/HLD/Bstrait/BeringStraitSeasonalInterannualChange2017.html)

I created a new thread for the Bering Strait a while back because I believe that this will become a serious problem for the Arctic. If anyone is interested in discussing this, let's do it there.
https://forum.arctic-sea-ice.net/index.php/topic,2989.0.html (https://forum.arctic-sea-ice.net/index.php/topic,2989.0.html)
Title: Re: The 2020 melting season
Post by: wdmn on April 23, 2020, 04:08:19 PM
Five day Forecast Wind + Temp @ Surface

Between this wind forecast and Aluminium's most recent post, it's clear that the ice around Svalbard is (going to be) moving around more already than it did all last year (if I remember correctly), when it stayed pressed against the Island and never melted. Could be an early indication that the Atlantic side will have a worse melt season than it did last year.
Title: Re: The 2020 melting season
Post by: Phoenix on April 23, 2020, 04:14:12 PM
latest DMI thickness map
Do you see the blue in the Chukchi sea? I think that's hot pacific water that will be penetrating deep into the CAP CAB this year. As I wrote here before, I believe that the slowdown of the AMOC is causing more pacific water to enter the arctic ocean. That water is also hotter now, so you get a double whammy. And strike three is this missing arm of thick ice that should be protecting the CAB. But that arm is also missing this season.


i think it's pretty well established that there is already sufficient heat in the CAB to melt all of the CAB ice. The barrier is that the heat exists below the fresh water lens on the surface where the ice exists.

If one wants to make the case that incremental Pacific intrusion into the CAB will make a big dent in the CAB ice, they should consider how that heat gets to the surface of the CAB.
Title: Re: The 2020 melting season
Post by: Freegrass on April 23, 2020, 04:31:29 PM
latest DMI thickness map
Do you see the blue in the Chukchi sea? I think that's hot pacific water that will be penetrating deep into the CAP CAB this year. As I wrote here before, I believe that the slowdown of the AMOC is causing more pacific water to enter the arctic ocean. That water is also hotter now, so you get a double whammy. And strike three is this missing arm of thick ice that should be protecting the CAB. But that arm is also missing this season.


i think it's pretty well established that there is already sufficient heat in the CAB to melt all of the CAB ice. The barrier is that the heat exists below the fresh water lens on the surface where the ice exists.

If one wants to make the case that incremental Pacific intrusion into the CAB will make a big dent in the CAB ice, they should consider how that heat gets to the surface of the CAB.
As you well know, I'm just an amateur, but I think that the water that is entering from the pacific is mostly fresh melt water from the surrounding mountains. So I think that this water should stay on top of the colder fresh water that's already in the basin, no?

Edit: Uniqorn posted an excellent graphic of the salinity on the Pacific side.
https://forum.arctic-sea-ice.net/index.php/topic,2417.msg260835.html#msg260835 (https://forum.arctic-sea-ice.net/index.php/topic,2417.msg260835.html#msg260835)
Title: Re: The 2020 melting season
Post by: Phoenix on April 23, 2020, 08:42:25 PM
latest DMI thickness map
Do you see the blue in the Chukchi sea? I think that's hot pacific water that will be penetrating deep into the CAP CAB this year. As I wrote here before, I believe that the slowdown of the AMOC is causing more pacific water to enter the arctic ocean. That water is also hotter now, so you get a double whammy. And strike three is this missing arm of thick ice that should be protecting the CAB. But that arm is also missing this season.


i think it's pretty well established that there is already sufficient heat in the CAB to melt all of the CAB ice. The barrier is that the heat exists below the fresh water lens on the surface where the ice exists.

If one wants to make the case that incremental Pacific intrusion into the CAB will make a big dent in the CAB ice, they should consider how that heat gets to the surface of the CAB.
As you well know, I'm just an amateur, but I think that the water that is entering from the pacific is mostly fresh melt water from the surrounding mountains. So I think that this water should stay on top of the colder fresh water that's already in the basin, no?

Edit: Unicorn posted an excellent graphic of the salinity on the Pacific side.
https://forum.arctic-sea-ice.net/index.php/topic,2417.msg260835.html#msg260835

Uniqourn's video is demonstrating the accumulation of fresh water in the Beaufort Gyre. While the destination of that water is adjacent to the Pacific side, the source of that water is the entire Arctic. The gyre is anomalous because local weather conditions induce a prevailing anticyclonic (clockwise) spin. in the N. Hemisphere, Coriolis force causes the surface water to concentrate under an anticyclonic spin.

That's ~ 20% of the entire freshwater supply on earth already sitting on top of the gyre. Any seasonal incremental freshwater intrusion from local mountain runoff is a drop in the bucket. And that incremental drop is likely to be assimilated into the gyre and not headed for the CAB.

At some point, the weather conditions will reverse the gyre spin and cause a lot of fresh water to be released, but Coriolis forces are almost certainly going to push that eventual current toward N. America during periodic release and be directed toward the N. Atlantic via Baffin Bay.

The CAB is well defended. It won't give up easily.
Title: Re: The 2020 melting season
Post by: oren on April 23, 2020, 08:52:53 PM
A request to all, please avoid quoting long nested quotes unless necessary. You need to edit the quoted post and only leave that material which you are referring to.
Title: Re: The 2020 melting season
Post by: Freegrass on April 23, 2020, 09:02:35 PM
Uniqourn's video is demonstrating the accumulation of fresh water in the Beaufort Gyre.
You're going way off topic. I was referring to that video because it shows 2 impulses of salt water entering the gyre from the pacific side, right around the time when freezing starts. So I think that's salt water from the pacific that's entering the Chukchi sea when the melting - and thus the supply of fresh water - ends.
Title: Re: The 2020 melting season
Post by: uniquorn on April 23, 2020, 09:26:11 PM
That animation is a model of salinity (http://bulletin.mercator-ocean.fr/en/permalink/PSY4/animation/3/20190801/20200122/2/4) at 318m depth. A pulse of increased salinity of that size is likely to come from denser, higher salinity water below.
Title: Re: The 2020 melting season
Post by: Freegrass on April 23, 2020, 09:39:28 PM
That animation is a model of salinity (http://bulletin.mercator-ocean.fr/en/permalink/PSY4/animation/3/20191101/20200122/2/1) at 318m depth. A pulse of increased salinity of that size is likely to come from denser, higher salinity water below.
Thanks for Uniquorn. I had noticed the depth, and that's why I wasn't entirely sure if it could come from the Bering strait. But it does seem to come from that side. Especially that first pulse.

Anyway... this is way out of my league...
Thanks for the reply!

Edit: I can see it now that this pulse is coming from the bottom. Got it! Thanks.
Title: Re: The 2020 melting season
Post by: Phoenix on April 23, 2020, 09:52:07 PM
avoid quoting long nested quotes unless absolutely necessary.

"Absolutely necessary" is a tough standard. The quote function is never absolutely necessary. It is however very beneficial in many instances as it enhances efficiency of understanding of simultaneous disparate discussions in a thread.

In the above example (which I assume is the source of your comment), Freegrass has advanced a hypothesis which I felt was flawed and I have liberally cut out extraneous elements along the way. IMO, there is not a lot of "fat' retained from the previous comments.
Title: Re: The 2020 melting season
Post by: oren on April 23, 2020, 10:09:30 PM
Good point Phoenix, "absolutely" removed from my comment. And I was referring to all posters in general, though that particular nested quote (which is ok) was the trigger
Title: Re: The 2020 melting season
Post by: Phoenix on April 23, 2020, 10:15:40 PM
Anyway... this is way out of my league...

The important thing is that you learned something in the process and I'll bet a few lurkers learned something as well. I certainly learned something. It's not a sin to put forth possibilities that are eventually debunked. It's an essential element of the learning process.
Title: Re: The 2020 melting season
Post by: Freegrass on April 23, 2020, 10:51:40 PM
The important thing is that you learned something in the process and I'll bet a few lurkers learned something as well. I certainly learned something. It's not a sin to put forth possibilities that are eventually debunked. It's an essential element of the learning process.

So true. If you're not making mistakes, you're not learning.
Title: Re: The 2020 melting season
Post by: wili on April 24, 2020, 03:10:37 AM
"So true. If you're not making mistakes, you're not learning."

Indeed.

I've always thought that students should get asked 'why do you have this F on your record'

Instead they should be challenged with 'why didn't you ever get an F on your record? Did you never really challenge yourself that much?'
Title: Re: The 2020 melting season
Post by: Freegrass on April 24, 2020, 11:37:11 AM
We're losing a lot of ice in the Bering sea as well it seems...
Title: Re: The 2020 melting season
Post by: Jim Hunt on April 24, 2020, 11:41:39 AM
If one wants to make the case that incremental Pacific intrusion into the CAB will make a big dent in the CAB ice, they should consider how that heat gets to the surface of the CAB.

Back to the science  :)

For starters how about Timmermans et al. (2018)?

https://advances.sciencemag.org/content/4/8/eaat6773

From the abstract:

Quote
The halocline stratification strongly inhibits vertical heat fluxes from these warm layers.

However, the fate of sea ice is acutely sensitive to changes in ocean heat flux of as little as 1 W m−2
Title: Re: The 2020 melting season
Post by: grixm on April 24, 2020, 03:09:40 PM
It looks like the DMI volume may have passed the season maximum.

(https://forum.arctic-sea-ice.net/proxy.php?request=http%3A%2F%2Fpolarportal.dk%2Ffileadmin%2Fpolarportal%2Fsea%2FCICE_curve_thick_LA_EN_20200423.png&hash=fdfcf03dcff8a20f33f4c9ef6fb8b712)
Title: Re: The 2020 melting season
Post by: Freegrass on April 24, 2020, 04:10:52 PM
Back to the science  :)

For starters how about Timmermans et al. (2018)?

https://advances.sciencemag.org/content/4/8/eaat6773 (https://advances.sciencemag.org/content/4/8/eaat6773)


Quote
It remains a possibility that some of the NCS warming could be attributed to increased heat flux through the Bering Strait (18) [warm inflows through the Bering Strait have, at least, been shown to be essential in initiating the positive ice-albedo feedback (19)]. Uncertainties in the past decades’ record of heat influx through the Bering Strait (particularly the lack of measurements in the top 20 m) preclude us from ruling this out.
Quote
In the coming years, however, excess BG halocline heat will give rise to enhanced upward heat fluxes year-round, creating compound effects on the system by slowing winter sea ice growth.
Title: Re: The 2020 melting season
Post by: Davidsf on April 24, 2020, 04:22:49 PM
Thank you for the chart grixm. It's worrying to see this year leading in that metric. Though it does appear that recent years bunch together come summer.
Title: Re: The 2020 melting season
Post by: jdallen on April 24, 2020, 05:30:08 PM
It looks like the DMI volume may have passed the season maximum.
<snip>
Thank you for the chart grixm. It's worrying to see this year leading in that metric. Though it does appear that recent years bunch together come summer.

This is actually the most alarming graph I've seen in a while.

Wipneus's data has us tracking along the 2010's average for most metrics.  I'm wondering why this one is diverging from that?
Title: Re: The 2020 melting season
Post by: jdallen on April 24, 2020, 05:37:34 PM
We're losing a lot of ice in the Bering sea as well it seems...
... and even at that, the Bering is better off at this time than it has been for several years.

It will melt out entirely without question.  (as far as the ice is concerned) It is mostly a side show, except in so far as it can affect the Chukchi.

Where my concern is focused is the Eurasian peripheral seas - Chukchi, ESS, Laptev & Kara.

 Early melt ponds and open water significantly reduce regional albedo and increase heat capture during a time of rising insolation. If they are attacked early in the melt season, that will have serious implications for the CAB, as they buttress the main pack.
Title: Re: The 2020 melting season
Post by: Freegrass on April 24, 2020, 05:48:55 PM
Early melt ponds and open water significantly reduce regional albedo and increase heat capture during a time of rising insolation. If they are attacked early in the melt season, that will have serious implications for the CAB, as they buttress the main pack.
I read on another thread that insolation starts to matter around 7 weeks before the summer solstice? And we're 8 weeks off now if I counted right? So this couldn't come at a worse time. That open water isn't going to refreeze all that much, will it?
Title: Re: The 2020 melting season
Post by: Milwen on April 24, 2020, 05:49:24 PM
Is it just me or there are darker areas in Nares Strait? Looks like we will see opening of Nares really soon.

(https://i.imgur.com/EHbzD6X.png)
Title: Re: The 2020 melting season
Post by: oren on April 24, 2020, 05:53:13 PM
Wipneus's data has us tracking along the 2010's average for most metrics.  I'm wondering DMI is diverging from that?
Every year the question of DMI volume comes up. The short answer is that it's less reliable than PIOMAS and Cryosat/SMOS. Specifically it seems to be missing the large volume buildup next to Svalbard and FJL, but I haven't made a scientific comparison.
There is a thread for comparing PIOMAS to Cryosat, I'm not sure if there one comparing DMI volume to the others.
Title: Re: The 2020 melting season
Post by: blumenkraft on April 24, 2020, 06:20:53 PM
Is it just me or there are darker areas in Nares Strait? Looks like we will see opening of Nares really soon.

It's still way below freezing and there are no strong southward winds forecasted. I think a breakup is rather unlikely just now.
Title: Re: The 2020 melting season
Post by: F.Tnioli on April 24, 2020, 07:36:14 PM
Thank you for the chart grixm. It's worrying to see this year leading in that metric. Though it does appear that recent years bunch together come summer.
I join the tanks to grixm for the graph; much appreciated, and definitely timely per concerns further in this post.

I apologize for somewhat lengthy remainder of this post, but i think this is way too important; like, 2020's "must know" thing for the melting season (and for lots of other things too).

This is in response to the reference of "recent years" by Davidsd. This year is much different from recent years, and much more so than lots of people here could probably imagine.

1. China stopped most of its transport and industries for a fair while, and lots of it - half, give or take - are not back even now. This is now being followed globally: fuel burning by mankind is decreasing by the day, as reflected by oil prices;

2. This means less aerosols in the athmosphere, to say the least. Plenty cities in China were observing the stars clearly for the 1st time in decades, so strong was reduction in air pollution there. The normal effect of global dimming at the surface is quite massive on average over continents, too - over 10%, at places well over 15%, as was discovered by both pan-evaporation measurements, other methods and eventually multi-national 4-year INDOEX measurement effort (some details freely available here: http://www.bbc.co.uk/sn/tvradio/programmes/horizon/dimming_trans.shtml ). In the same piece one can also find summary of findings about direct effect of absense of jet contrails, which was found to be much bigger and more rapid in practice than anticipated.

3. As a result, right now (as well as progressively stronger during last couple months as the situation develops) - significantly less sunlight gets "caught" by aerosols before it reaches surface, which means less of cyclones (direct consequence of comparatively less heat content in the air), so more shiny days on average scale, and faster melt ponding / top melt in the local scale. So far, most of GHG effect - in the Arctic as well as around the globe - was negated by aerosols in this way, and lots of it still is, but the changes are big enough to already be a game-changer as far as ASI melting season is concerned as a whole.

To understand the scale and importance of those effects, it is enough to remind oneself that industrial activities since the industrial revolution have injected nearly 5000 Tg of SO2 into the athmosphere, with recent years being ~7...10 Tg/year - and that famous Pinatubo eruption, responsible for significant cooling of whole Earth's climate, released only ~1 Tg of SO2. Thus, even "modest" 10% cut of aerosol emissions by mankind can produce changes comparable in magnitude to Pinatubo eruption - except not to cooling, but to warming the climate. Further details about how aerosols work and plenty references for great number of good papers - can be seen here: https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2015RG000511 .

That same piece also describes timescales relevant for aerosols' lifetime in the athmosphere, which depending on type, size and source of a particle will vary from some hours to some months - with everything tropospheric leaning towards much shorter lifetimes (days to few weeks at best, usually) as precipitation washes 'em down to surface.

Same piece also mentions the following processes, to give a short quote here (by bold):

"In the stratosphere, strong zonal winds lead to fast homogenization of aerosols and tracers in the zonal direction, while vertical and meridional transport is controlled by the BDC [Holton et al., 1995; Butchart, 2014]. The BDC results from the breaking of upward propagating waves in the stratosphere that lead to a diabatic residual circulation [Holton, 2004]. The residual circulation is characterized by ascent over the tropics, poleward motion in the extratropics, and subsidence over the high latitudes, in particular over the winter polar vortex, ...".

So, with rather big uncertainties about how yet worse microbiological situation will become in the following weeks and months, but with rather big certainty that lots of intercontinental jet flights over the Arctic are not happening and won't be happening any time soon, i can easily conclude that "recent years" are not a predictor of anything, now.
Title: Re: The 2020 melting season
Post by: pearscot on April 25, 2020, 01:09:06 AM
Is it just me, or has it been exceptionally clear above Greenland for a while now (or at least the last week)?? I'm just so interested in that entire region after what happened last year. I have no idea if that crack will appear again, but if it does I think that will signal that some significant changes have occurred between 2012-now.

That said, I also find ocean currents/Atlantification very interesting as well. Most of the Atlantic has been above average in the tropics this year - I realize that's far removed from the arctic, but it appears as though this will be a neutral el nino/la nina year. 
Title: Re: The 2020 melting season
Post by: Niall Dollard on April 25, 2020, 02:48:50 AM
Thank you for the chart grixm. It's worrying to see this year leading in that metric. Though it does appear that recent years bunch together come summer.

3. As a result, right now (as well as progressively stronger during last couple months as the situation develops) - significantly less sunlight gets "caught" by aerosols before it reaches surface, which means less of cyclones (direct consequence of comparatively less heat content in the air), so more shiny days on average scale, and faster

Do you have any stats to back up  this  ? Re cyclones.
Title: Re: The 2020 melting season
Post by: VaughnAn on April 25, 2020, 07:17:58 AM
Thank you for the chart grixm. It's worrying to see this year leading in that metric. Though it does appear that recent years bunch together come summer.

3. As a result, right now (as well as progressively stronger during last couple months as the situation develops) - significantly less sunlight gets "caught" by aerosols before it reaches surface, which means less of cyclones (direct consequence of comparatively less heat content in the air), so more shiny days on average scale, and faster

Do you have any stats to back up  this  ? Re cyclones.

There's a "wannabe tropical storm" in the East Pacific right now.  Maybe the earliest on record for that region if it develops.  The NHC currently gives it an 80% chance to develop.
Title: Re: The 2020 melting season
Post by: Jim Hunt on April 25, 2020, 11:03:43 AM
This is actually the most alarming graph I've seen in a while.

Wipneus's data has us tracking along the 2010's average for most metrics.  I'm wondering why this one is diverging from that?

See: http://GreatWhiteCon.info/2020/03/facts-about-the-arctic-in-april-2020/#Apr-25

Quote
With another week's worth of reanalysed data now processed, it now seems certain that the CryoSat-2/SMOS Arctic sea ice volume maximum was 18469 km³ on April 6th

Title: Re: The 2020 melting season
Post by: Pavel on April 25, 2020, 11:13:46 AM
Considering the last year low September extent, the highest albedo warming potential and late start of refreeze I'm not surprised the current volume is one of the lowest or even the lowest on record. Yes, it was cold north of 80 latitude but much of that ice has been exporeted through the Fram strait.
Good news is the weather forecasts don't promise extreme melting events in the CAB, but the land snow will melt quickly in some places
Title: Re: The 2020 melting season
Post by: gandul on April 25, 2020, 11:59:00 AM
Is it just me or there are darker areas in Nares Strait? Looks like we will see opening of Nares really soon.

(https://i.imgur.com/EHbzD6X.png)

Whether that's snow cover loss, or material deposition, this is very anomalous.
Wasn't there a recent wave above 0C?
Title: Re: The 2020 melting season
Post by: gandul on April 25, 2020, 12:04:49 PM
It looks like the DMI volume may have passed the season maximum.
<snip>
Thank you for the chart grixm. It's worrying to see this year leading in that metric. Though it does appear that recent years bunch together come summer.

This is actually the most alarming graph I've seen in a while.

Wipneus's data has us tracking along the 2010's average for most metrics.  I'm wondering why this one is diverging from that?
Because it's crap, JD, after so many years you should know better.  ;)
Title: Re: The 2020 melting season
Post by: F.Tnioli on April 25, 2020, 01:12:07 PM
...
Do you have any stats to back up  this  ? Re cyclones.
I don't, but i did not look for, either. Was just general consideration, which i think is quite obvious: when it's some 10%...15% of sunlight normally much absorved by aerosols, "normally" means with recent-years-typical amount of fuel burning by mankind, - we'll have that much more heat mostly added to troposphere, and cyclones are driven by athmospheric heat. Substract from it, and less "of" cyclones will be around: less number as well as less intensity.

Important also: "less" means "less than would otherwise happen", and with ever-growing GHGs, the general trend is to _more_ of cyclones as years go by. So less aerosols will make it "less than would happen with both normal aerosol content and with normal GHG growth", which does not nesessarily mean "less than in recent years", since GHG growth is ongoing process.

It would surely be very interesting to see how many and how strong cyclones in the Arctic would end up happening, but obviously we're not yet at the point in time when this could be measured / quantified. This is a talk for the end of this melting season - about estimating cyclones' number, strength and effects on sea ice.

The above point about less aerosols present in the air remains game-changing despite the uncertainty about "absolute" number and strength of cyclones / cloudy days during this season, however, because higher actual insolation at the surface - i.e. few percent more sunlight reaching the ice directly, - will still produce greater melt "per sunny day" than in recent years. Especially with less jet contrails directly over the Arctic as per less jet liners crossing the Arctic back and forth, as was usual in exactly recent years. The effect is relatively small "directly", but multiplicated with further albedo feedback, of course - few percent faster melt produces few percent darker surfaces on average, which then add ever growing further extra melt into the picture.
Title: Re: The 2020 melting season
Post by: The Walrus on April 25, 2020, 03:01:52 PM
Considering the last year low September extent, the highest albedo warming potential and late start of refreeze I'm not surprised the current volume is one of the lowest or even the lowest on record. Yes, it was cold north of 80 latitude but much of that ice has been exporeted through the Fram strait.
Good news is the weather forecasts don't promise extreme melting events in the CAB, but the land snow will melt quickly in some places

Yes, the extent was lowest for two weeks at the end of October.  Since then, the growth in extent has been the highest since 2013, which was the highest in the satellite era.  I albedo would have been lower than recent years for most of the freezing season.  The maximum extent was higher than the average for the past decade.  I would not expect low volume, based on the cold temperatures, you mention.  The extent did drop quickly, as the melting season began, indicating a significant amount of thin ice.  However, even that has slowed.  Of course early melt is not indicative of the season to come.  This year has roughly the same extent as 2004, but I seriously doubt we will end up anywhere close to that year.
Title: Re: The 2020 melting season
Post by: Pavel on April 25, 2020, 03:09:58 PM
Is it just me or there are darker areas in Nares Strait? Looks like we will see opening of Nares really soon.

(https://i.imgur.com/EHbzD6X.png)

Whether that's snow cover loss, or material deposition, this is very anomalous.
Wasn't there a recent wave above 0C?
It had turned gray after a strong cyclone in early April. The north of Greenland is also gray
Title: Re: The 2020 melting season
Post by: gandul on April 25, 2020, 07:22:42 PM
Wow. Blown by the wind.

Perhaps it wasn't only one storm, only that the bare ground has become visible after the last winds. It's been a winter of hellish storms and above average Fram ice export.
Title: Re: The 2020 melting season
Post by: uniquorn on April 25, 2020, 07:56:44 PM
comparison of NE greenland, apr24 or apr25, 2012-2020
https://go.nasa.gov/2S9iTlZ  click to run
Title: Re: The 2020 melting season
Post by: kassy on April 25, 2020, 11:08:42 PM
It is OT.
<Thank you Kassy. O>
Title: Re: The 2020 melting season
Post by: Niall Dollard on April 26, 2020, 02:13:27 AM
Stats from Alert indicate that snow depth is about 3cm. So it is low. Lower than it has been compared to recent years as Uniquorn's vid shows.

Temperatures have not risen above -7 C in the past month. So the bareness is more dryness related rather than melting. Sublimation can continue to reduce snow depth unless there is any new snowfall. But Alert is statistically a very dry spot.

Title: Re: The 2020 melting season
Post by: VeliAlbertKallio on April 26, 2020, 02:22:02 AM
Coronavirus has certainly helped to brighten skies also on Subarctic and Arctic regions. Normally it is difficult to see 80km across the Baltic Sea from Finland to Estonia.  The reduction of nitrous oxides makes it possible now to see much more easily across the Gulf of Finland from Helsinki to Tallinn. Normally such viewings are possible for electric lighting or during sunset or sunrise when contrast is high, but currently it is possible to see continually and even through midday's bright circumstances.  8)

https://www.hs.fi/kotimaa/art-2000006486374.html

Finland is quite high latitude, almost sliced to two halves by the Arctic Circle, or ~1/3 to ~2/3 ratio. If light can travel much further horizontally unhindered by aerosols, it certainly is transparent vertically. Let's see if this removal of global dimming effect lives up to its name or if the scare was exaggerated. Central England Temperature (CET) was since beginning of this year to this week +2.26C above 1960-2000 average.  :-[

...
Do you have any stats to back up  this  ? Re cyclones.
I don't, but i did not look for, either. Was just general consideration, which i think is quite obvious: when it's some 10%...15% of sunlight normally much absorved by aerosols, "normally" means with recent-years-typical amount of fuel burning by mankind, - we'll have that much more heat mostly added to troposphere, and cyclones are driven by athmospheric heat. Substract from it, and less "of" cyclones will be around: less number as well as less intensity.

Important also: "less" means "less than would otherwise happen", and with ever-growing GHGs, the general trend is to _more_ of cyclones as years go by. So less aerosols will make it "less than would happen with both normal aerosol content and with normal GHG growth", which does not nesessarily mean "less than in recent years", since GHG growth is ongoing process.

It would surely be very interesting to see how many and how strong cyclones in the Arctic would end up happening, but obviously we're not yet at the point in time when this could be measured / quantified. This is a talk for the end of this melting season - about estimating cyclones' number, strength and effects on sea ice.

The above point about less aerosols present in the air remains game-changing despite the uncertainty about "absolute" number and strength of cyclones / cloudy days during this season, however, because higher actual insolation at the surface - i.e. few percent more sunlight reaching the ice directly, - will still produce greater melt "per sunny day" than in recent years. Especially with less jet contrails directly over the Arctic as per less jet liners crossing the Arctic back and forth, as was usual in exactly recent years. The effect is relatively small "directly", but multiplicated with further albedo feedback, of course - few percent faster melt produces few percent darker surfaces on average, which then add ever growing further extra melt into the picture.
Title: Re: The 2020 melting season
Post by: Aluminium on April 26, 2020, 09:45:50 AM
April 20-25.

2019 (https://forum.arctic-sea-ice.net/index.php/topic,2591.msg196848.html#msg196848).
Title: Re: The 2020 melting season
Post by: grixm on April 26, 2020, 09:49:52 AM
April 20-25.


Wow, sea ice has hit Bear Island
Title: Re: The 2020 melting season
Post by: oren on April 26, 2020, 10:02:22 AM
April 20-25.
The circular movement pushing the ice away in Kara and Laptev and exporting ice into the Barents and the Fram is like the worst possible scenario for the ice at this time of year, especially as there is a significant volume concentration next to FJL and Svalbard and at the export staging area north of the Fram.
Title: Re: The 2020 melting season
Post by: gandul on April 26, 2020, 11:33:11 AM
However the Beaufort sea remains closed.
Beaufort melt extent in Summer is quite sensitive to the existence of early open water.

Title: Re: The 2020 melting season
Post by: Stephan on April 26, 2020, 12:53:31 PM
April 20-25.

The ice in Kara and Eastern Barents Sea looks very vulnerable to me.

PS Thank you aluminium for your regular updates  :)
Title: Re: The 2020 melting season
Post by: be cause on April 26, 2020, 03:35:41 PM
^^ seconded .. and a great doorway to last years page as a reminder .

  2007 and much more so 2012 and 2016 also had early active melting seasons in Kara . b.c.
Title: Re: The 2020 melting season
Post by: blumenkraft on April 26, 2020, 06:32:00 PM
... consider that the ozone level animations are a kind of proxy for the polar stratospheric circulation, also that the stratospheric ozone in the polar vortex will increase rather dramatically at the onset of a Sudden Stratospheric Warming (SSW). Such events do have relevance in the melting season. For a simple example please see:

]https://ozonewatch.gsfc.nasa.gov/facts/warming_NH.html (https://ozonewatch.gsfc.nasa.gov/facts/warming_NH.html)

Actually it is a bit more complicated than the simple view expressed above, see:

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/jgrd.50651 (https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/jgrd.50651)
https://arxiv.org/abs/1807.11750 (https://arxiv.org/abs/1807.11750)

Thus, I think that the ozone measurement animations are relevant to melting, at least in the early part of the melting season.

QED! :)

The ozone layer, 19.04. to 26.04.
Title: Re: The 2020 melting season
Post by: blumenkraft on April 26, 2020, 06:33:37 PM
7-day hindsight mean temperature & DMI 80°N 2m Temperature
Title: Re: The 2020 melting season
Post by: blumenkraft on April 26, 2020, 06:34:08 PM
Ice drift map.
Title: Re: The 2020 melting season
Post by: blumenkraft on April 26, 2020, 06:34:42 PM
Fram export via SAR.
Title: Re: The 2020 melting season
Post by: johnm33 on April 26, 2020, 09:29:03 PM
Beaufort (https://media.giphy.com/media/TFIdWDeBEFYoSVbk7W/giphy.gif) ice is shattered, won't hold a crack just spreads out, which implies it's very fluid.
Title: Re: The 2020 melting season
Post by: pearscot on April 26, 2020, 10:21:27 PM
comparison of NE greenland, apr24 or apr25, 2012-2020
https://go.nasa.gov/2S9iTlZ  click to run

Wow, thank you for posting that. If you took away the years at the bottom it just looks like you're advancing the days during a normal melt year.

I can't wait to see what unfolds in that region this year.

Title: Re: The 2020 melting season
Post by: uniquorn on April 26, 2020, 10:43:19 PM
Beaufort (https://media.giphy.com/media/TFIdWDeBEFYoSVbk7W/giphy.gif) ice is shattered, won't hold a crack just spreads out, which implies it's very fluid.
I think you look at the Beaufort more often than me so to check here is worldview terra modis ( https://go.nasa.gov/3cNr4MB) mar3-apr25, medium contrast to enhance the fine cracks. Ascat is inset to show overall movement, which isn't much. Obviously visible is a different view to compressive strength
2020 has certainly been a different year for Beaufort drift.
Title: Re: The 2020 melting season
Post by: Glen Koehler on April 27, 2020, 02:50:58 AM
April 20-25.
2019 (https://forum.arctic-sea-ice.net/index.php/topic,2591.msg196848.html#msg196848).
      Thanks as always Aluminium.  One of the best synoptic views.  Is there a scale to interpret what the different levels of gray to black shading tell us about the condition of the ice?
Title: Re: The 2020 melting season
Post by: Niall Dollard on April 27, 2020, 08:34:40 AM
Here is the accompanying legend, Glen.

Link :

https://seaice.uni-bremen.de/sea-ice-concentration/amsre-amsr2/
Title: Re: The 2020 melting season
Post by: F.Tnioli on April 27, 2020, 10:28:15 AM
I took a bit of time to verify if my above concern about jet contrails now mostly missing from Arctic sky is of any practical significance, and what i found - is yet worse than i throught it'd be. Namely, i found that:

- during recent years, there was continuous jet liner air traffic over Arctic on the scope of many hundreds flights per day by only US air lines, and most likely well over a thousand flights total if to include non-US international air lines flying this North Route, as they call over-Arctic airways;

- but now, ICAO says that in April 2020, global international passenger capacity "so far" suffered 91 percent reduction.

And obviously, most of remaining - for now - 9% of international flights are not between usual sides of trans-Arctic flights: Europe and US are most affected by the virus, so quite nobody would be eager to accept lots of flights from those parts - not now, nor for (at least) a few months forward.

So, this is fully comparable to the 9/11 case of almost whole US jet liner fleet grounded for three days after 9/11, described in that BBC transcript i linked in my earlier post: "During the grounding the temperature range jumped by over a degree Celsius. DR DAVID TRAVIS: This was the largest temperature swing of this magnitude in the last thirty years". Except this time, it ain't for three days, it's for months, and apparently well past May. Which means 0/0 night time. No cooling, only heating up the surface whenever not cloudy.

I tend to value practical measurements of this kind higher than modelling, and so it seems to me absense of jet contrails alone will bring in - over weeks of 24/7 sunshine unobstracted by contrails - _several_ degrees C increase to surface temperatures.

Can't see how anything less can be. With recent years at times quite walking the edge, it seems this time BOE is quite at the door, and possibly with a big bang. If i miss something crucial, please tell. I'd want to...
Title: Re: The 2020 melting season
Post by: blumenkraft on April 27, 2020, 10:56:54 AM
However it turns out to be, i bet next year this time we know way better how to quantify the masking effects. This is a science opportunity - the Earth on a petri dish.
Title: Re: The 2020 melting season
Post by: gerontocrat on April 27, 2020, 11:10:43 AM
However it turns out to be, i bet next year this time we know way better how to quantify the masking effects. This is a science opportunity - the Earth on a petri dish.

This is a science opportunity - the Earth humans on a petri dish.
Title: Re: The 2020 melting season
Post by: blumenkraft on April 27, 2020, 11:35:48 AM
Yeah, that too i'm afraid.  :-\
Title: Re: The 2020 melting season
Post by: F.Tnioli on April 27, 2020, 11:52:24 AM
Some opportunities are better not attempted too early, though. Unintended consequences of premature experimentation can be quite upsetting. :·)

<Please avoid posting OT YouTube videos in the main thread, though I appreciate the humor. O>
Title: Re: The 2020 melting season
Post by: Niall Dollard on April 27, 2020, 12:59:39 PM
I took a bit of time to verify if my above concern about jet contrails....

Re Contrails. Rather than clutter up this thread I have posted a reply in this thread:


https://forum.arctic-sea-ice.net/index.php/topic,606.msg261760.html#msg261760
Title: Re: The 2020 melting season
Post by: ajouis on April 27, 2020, 02:36:57 PM
From what I understand, the slowing of the gulf stream had an impact on the sea ice, with atlantic ice retreating less than pacific or landfast ice. How does the increased insolation in this melt season, with the diminution of economic activity linked aerosols, affect that?
Title: Re: The 2020 melting season
Post by: pearscot on April 27, 2020, 05:53:28 PM
This is so wild to me! Granted, I'm not attempting to say that April resembles September of 2019, but I am using this to show how the ice above Greenland continues to surprise me with its mobility. Ice is most certainly still held to the coast an inlets, however with so much sunlight, and lack of clouds, whatever darker areas will most certainly absorbing energy. Nonetheless, there is still much for to follow in such a dynamic system.

Title: Re: The 2020 melting season
Post by: grixm on April 27, 2020, 07:39:25 PM
According to Nico Sun's area calculations, we are back in spot #1 today.

Title: Re: The 2020 melting season
Post by: Freegrass on April 27, 2020, 10:52:53 PM
According to Nico Sun's area calculations, we are back in spot #1 today.
And I think that's where we'll stay all season...
Title: Re: The 2020 melting season
Post by: Phoenix on April 27, 2020, 11:28:23 PM
According to Nico Sun's area calculations, we are back in spot #1 today.
And I think that's where we'll stay all season...

IMO, this is a low effort, no value added post. Someone should open a prediction thread for the non-science of guessing future weather events.
Title: Re: The 2020 melting season
Post by: bbr2315 on April 28, 2020, 01:46:05 AM
According to Nico Sun's area calculations, we are back in spot #1 today.
And I think that's where we'll stay all season...

IMO, this is a low effort, no value added post. Someone should open a prediction thread for the non-science of guessing future weather events.
We have seen a massive drop in aerosols and the conversation preceded this post further discussing the impact of contrails.

I think Freegrass is correct. The aerosol problem this year is unprecedented. A page or two back, or it may have been another thread, someone posted that we contribute roughly 8 Pinatubos of SO2 a year to the atmosphere. What will the impact be of one less Pinatubo a year? Or two? Or three? Or even four? The best case is we have two "reverse Pinatubos" the worst, is probably three or four. That is a recipe for absolute catastrophe in the Arctic, especially when you compound it with the impact of contrails / etc.
Title: Re: The 2020 melting season
Post by: Shared Humanity on April 28, 2020, 02:45:15 AM
According to Nico Sun's area calculations, we are back in spot #1 today.
And I think that's where we'll stay all season...

IMO, this is a low effort, no value added post. Someone should open a prediction thread for the non-science of guessing future weather events.

Only outdone by your response.
Title: Re: The 2020 melting season
Post by: ajouis on April 28, 2020, 03:52:23 AM
According to Nico Sun's area calculations, we are back in spot #1 today.
And I think that's where we'll stay all season...

IMO, this is a low effort, no value added post. Someone should open a prediction thread for the non-science of guessing future weather events.
We have seen a massive drop in aerosols and the conversation preceded this post further discussing the impact of contrails.

I think Freegrass is correct. The aerosol problem this year is unprecedented. A page or two back, or it may have been another thread, someone posted that we contribute roughly 8 Pinatubos of SO2 a year to the atmosphere. What will the impact be of one less Pinatubo a year? Or two? Or three? Or even four? The best case is we have two "reverse Pinatubos" the worst, is probably three or four. That is a recipe for absolute catastrophe in the Arctic, especially when you compound it with the impact of contrails / etc.

It will definitely be bad for global warming, but we should wait and see in the arctic as it also means a strengthened jet stream and less storms
Title: Re: The 2020 melting season
Post by: Paul on April 28, 2020, 03:53:35 AM
According to Nico Sun's area calculations, we are back in spot #1 today.

No doubt an reduction in extent plays a part in the area charts so the really low ice extent of Baffin Bay could be the main cause of this area chart being so low but still, its not a promising sign that is for sure.

It is interesting to note whilst extent is similar to that of 2016 and 2019, there is differences in where the ice is located. So 2016 has less ice than 2020 in the Barants and Beaufort seas whereas 2019 has less ice in the Bering and Chukchi seas than 2020. 2020 currently has less ice in Baffin Bay, the Kara and the Laptev seas than 2016/2019 so it will be interesting if 2020 can keep up with the drops of 2016 and 2019 as we head through May. If another region starts to have rapid melt then 2020 could indeed be lowest on record and by some margin potentially but we could see the early drops in Baffin Bay and the Kara seas slow down so probably a slow down in extent as a result.
Title: Re: The 2020 melting season
Post by: Phoenix on April 28, 2020, 03:55:08 AM

Only outdone by your response.

My post is an investment in the discussion about the desired scope of the thread. As a lurker, my experience has been that people like to tell themselves that this is a "science' thread. 

Guessing the future weather events of the 2020 melt season w/o any scientific rationale doesn't seem to fit the scope of a science thread. Yet there will be hundreds of comments cluttering up the thread to that effect.

For those of us who would easily make an even money bet that 2020 will not retain #1 position for the duration of the season, we can make an equally unscientific response projecting the opposite and then we can have an unscientific pissing contest about who is the better guesser.

I'll stick with 2012 as the likely record holder in volume and extent come September. Does that add anything of value to the readers? No. If I explain why I think that, that seems appropriate.

We have new moderators who have the opportunity to look at this with a fresh perspective and provide guidance.
Title: Re: The 2020 melting season
Post by: oren on April 28, 2020, 04:50:24 AM
The new moderator's long-winded stream-of-consciousness position about this thread is:
* Off-Topic comments, jokes and other "nonsense" are always welcome on the forum in appropriate threads, but not on the melting season thread, one of the highest-rating threads that is home to many lurker readers.
* Personally-charged comments and slights of honor should be avoided (even when justified...), as they necessarily create back and forth posts and increase clutter. And are of course impolite.
* Comments about comments, i.e. meta-discussion, should be minimized. Not necessarily avoided, but reduced and used with care. Use "report to moderator" or PM me about posts that you believe should be dealt with, but be aware that I am monitoring this thread continuously.
* General long term predictions about the season ("I think a BOE is impossible this year") are better off in a separate thread, and I am happy that such a one was recently opened. The exception is extrapolations of current data and situations ("I think the high CAB thickness precludes a meltout, based on average melting patterns").
* Deep discussions about scientific issues, which certainly could impact the melting season, should be held in separate threads. For example, contrails and their effects on sea ice, aerosols or lack thereof, La Nina, the Blob, soot from China or the fires soon to be in Siberia, etc., while a few comments on each such issue are welcome on this thread. Once it becomes heavy and arguments are flying around, or various papers posted, move it elsewhere. Here it will be lost and will disrupt the news flow.
* This thread is mainly about actual developments happening during the melting season, and comparisons with previous melting seasons.
* Comments about the data posted by JCG and Gero in the data thread should be posted in this thread, rather than in the data thread itself.
* Posters wishing to thank others for exceptional contributions (of which we happily have many) should consider using the Like button for most occasions.
* The moderator will use moderation in moderating, so as to avoid creating dissent and hurt feelings, and in consideration of his inexperience in such matters, but will act as necessary to ensure smooth and fruitful discussion.
* Often sporadic or borderline comments will not be dealt with to avoid disruption by the moderator, but similar comments might get the edit later when something becomes a repeated phenomenon.
* Should you undergo a moderation edit, please don't take this as a personal attack or as a hint that your contributions are unwelcome (unless specifically stated.....)
* If you are a lurker and are afraid or hesitant to post because of all these rules, be aware that new posters are treated more gently and are very welcome in their initial posting efforts. Bear in mind there is a "stupid" questions thread where you can ask most anything.
Title: Re: The 2020 melting season
Post by: F.Tnioli on April 28, 2020, 10:25:46 AM
We have seen a massive drop in aerosols and the conversation preceded this post further discussing the impact of contrails.

I think Freegrass is correct. The aerosol problem this year is unprecedented. A page or two back, or it may have been another thread, someone posted that we contribute roughly 8 Pinatubos of SO2 a year to the atmosphere. What will the impact be of one less Pinatubo a year? Or two? Or three? Or even four? The best case is we have two "reverse Pinatubos" the worst, is probably three or four. That is a recipe for absolute catastrophe in the Arctic, especially when you compound it with the impact of contrails / etc.
You probably refer to this post: https://forum.arctic-sea-ice.net/index.php/topic,3017.msg261429.html#msg261429 , in particular its paragraph following "3." one. And while "absolute catastrophe" is not likely to happen - i deem "absolute catastrophe" being the state when Arctic ocean top layers stay much above freezing point 24/365, like it was in the past when crocodiles lived there, - i concur that this melt season is likely to mark the beginning of the shift which will eventually lead to such a state. Huge thermal capacity, you know. Will take more than one or two summers to get there.

Obviously, melt ponding will be our early indicator of how dire a situation this melt season is likely to end up being. Extra attention to melt ponds, with perhaps finding new methods to quantify melt ponding better than we were able before, would very much help.
Title: Re: The 2020 melting season
Post by: F.Tnioli on April 28, 2020, 10:31:38 AM
...
* Personally-charged comments and slights of honor should be avoided (even when justified...), ...
Gentlemen - everyone! I ask us all to note the above bold / large (my enhancement) words and always remember them. At _all_ times.

I thank you, Oren, for putting it this way. This will allow us all to remain professional, here. Please strike down anyone violating this particular part - "even when _justified_" - without mercy. I think this is the greatest part you just did, for this topic!
Title: Re: The 2020 melting season
Post by: blumenkraft on April 28, 2020, 10:48:39 AM
I thank you, Oren

+1

Those are well thought out and reasonable boundaries.

Personally, i want to put emphasis on the

Quote
* Comments about the data posted by JCG and Gero in the data thread should be posted in this thread, rather than in the data thread itself.

point. For the love of God, please let the boys do their thing over there and don't clutter/distract!
Title: Re: The 2020 melting season
Post by: Freegrass on April 28, 2020, 12:33:56 PM
According to Nico Sun's area calculations, we are back in spot #1 today.
And I think that's where we'll stay all season...
Six off topic messages because of this one little sentence I wrote... That's insane! (seven now)
Title: Re: The 2020 melting season
Post by: SimonF92 on April 28, 2020, 12:36:52 PM
According to my mining script regional conditions are poor compared to the last decade.

Would it be more informative if I changed how many years the current year is compared to. Maybe post-2012 instead?

I suggest an automatic ban from this thread after 3-strikes, because its the same every year in the melting/freezing threads. Not going to answer anything re this post that isnt related to the ice.
Title: Re: The 2020 melting season
Post by: F.Tnioli on April 28, 2020, 01:33:01 PM
...
Would it be more informative if I changed how many years the current year is compared to. Maybe post-2012 instead?
...
Yes, it would be. 2013 and onwards is a whole new league of its own.
Title: Re: The 2020 melting season
Post by: nanning on April 28, 2020, 02:49:52 PM
^^
In an acceleratingly changing system, longer term averages may no longer be of significance.
Where to calibrate?
Title: Re: The 2020 melting season
Post by: Freegrass on April 28, 2020, 02:54:22 PM
The five day forecast looks boring. But maybe boring is good for a change?
Title: Re: The 2020 melting season
Post by: Aluminium on April 28, 2020, 03:05:04 PM
2020 tries to self-isolate.
Title: Re: The 2020 melting season
Post by: Stephan on April 28, 2020, 07:24:31 PM
According to my mining script regional conditions are poor compared to the last decade.

Which sea is represented by "dd", the first entry of your chart?
Title: Re: The 2020 melting season
Post by: Pavel on April 28, 2020, 08:35:12 PM
2020 tries to self-isolate.
I expect this year will be worse than 2019 especially if the Siberian side will melt out early, what is very likely. The Beaufort sea and CAA look more safely but everything can happen
Title: Re: The 2020 melting season
Post by: SimonF92 on April 28, 2020, 10:07:38 PM
Thanks for the input everyone, I will think about it. Its possible to make a facet-grid of several different baselines (2010+, 2013+ etc).

Stephan, i noticed that after I posted, its a mathematical-working column i forgot to trim that stands for 'delta-delta', shorthand for differences of differences. Ill fix the code as it shouldnt be there.
Title: Re: The 2020 melting season
Post by: Freegrass on April 28, 2020, 10:19:39 PM
Fast ice breaking off north of Greenland, close to Nares Fram Strait.
Title: Re: The 2020 melting season
Post by: Niall Dollard on April 28, 2020, 10:27:12 PM
Fast ice breaking off north of Greenland, close to Nares Strait.

Fram Strait
Title: Re: The 2020 melting season
Post by: Freegrass on April 28, 2020, 10:33:54 PM
Fast ice breaking off north of Greenland, close to Nares Strait.

Fram Strait
Thanks for the correction Niall! I always mix those two up...

That's early for fast ice break-off, isn't it?
Title: Re: The 2020 melting season
Post by: jdallen on April 28, 2020, 11:06:19 PM
NSIDC Total Area as at 27-Apr-2020 (5 day trailing average) 11,545,487 KM2         
         
Total Area         
 11,545,487    km2      
-490,913    km2   <   2010's average.
-69,638    km2   <   2019
-774,162    km2   <   2000's average.
         
 Total Change    -98    k   loss
Peripheral Seas   -67    k   loss
Central Seas___   -31    k   loss
<snippage>
- 2020 Area is -70 k less than 2019       

- An impressive loss,
<more snippage>
see https://cryospherecomputing.tk/

Area is tracking 2016 pretty closely.  It was saved from beating 2012 only by shifts in the weather in July as I recall.  As it was, ice quality and volume were still butchered.

It will be interesting to see if area drops below 2016 over the next few days, which considering how much vulnerable ice there is in peripheral seas, shouldn't be hard.
Title: Re: The 2020 melting season
Post by: Aluminium on April 29, 2020, 08:03:43 AM
April 23-28.

2019 (https://forum.arctic-sea-ice.net/index.php/topic,2591.msg197146.html#msg197146).
Title: Re: The 2020 melting season
Post by: Niall Dollard on April 29, 2020, 01:10:23 PM
That's early for fast ice break-off, isn't it?

I don't know FG.

Hard to know what is normal or typical anymore !

Early May last year was different because we had an open Nares Strait. Floes were continuously breaking off in the Lincoln Sea.

Then on May 10th, a crack rapidly spread eastwards from there, right along to Cape Morris Jesup . Next day crack rounded the top continued southeast down along north east coast of Greenland and then we had a huge separation all the way from NE Greenland coast all the way to the Nares Strait.
 
Title: Re: The 2020 melting season
Post by: F.Tnioli on April 29, 2020, 02:33:37 PM
...
It will be interesting to see if area drops below 2016 over the next few days, which considering how much vulnerable ice there is in peripheral seas, shouldn't be hard.
Interesting indeed, but needs to be observed in conjunction with data about ongoing cloud cover (or lack of) over said peripheral seas. There are two factors we expect to play a big role in the process - vulnerable state of ice and clean air, and yet they both are minimized when/where there is no sunlight present over any given peripheral sea, roughly speaking. Thus i'd say it's not just "if" area drops or not, - it's "if" area drops in those seas which are any well soaked in direct sunlight.

And to me it's also very interesting to see if we'll have more such areas than usual. Current weather / vortex effects of course overrides, but there is now that general effect of way less nuclei in clouds - so bigger water droplets / snowflakes, means precipitation should deplete clouds faster.
Title: Re: The 2020 melting season
Post by: Phoenix on April 29, 2020, 09:53:08 PM
April 23-28.

These gif's are an awesome contribution to the site and even better now that we can compare to last year. Pacific side was much more advanced in terms of 2D ice loss last year at this point. Atlantic side is further along this year where we see some open water N of 80N. The cliff at 82N which separates the Nansen Basin from the shallow Atlantic will get a good test this season.
Title: Re: The 2020 melting season
Post by: Milwen on April 29, 2020, 11:12:28 PM
We have liftoff north of Greenland, to the left of Nares

(https://i.imgur.com/btYvwpV.png)
Title: Re: The 2020 melting season
Post by: gerontocrat on April 29, 2020, 11:36:27 PM
Russia tells us to expect a warm Siberian late spring & early summer.
Title: Re: The 2020 melting season
Post by: grixm on April 30, 2020, 09:39:28 PM
Hmmm... 🤔

(https://forum.arctic-sea-ice.net/proxy.php?request=http%3A%2F%2Fpolarportal.dk%2Ffileadmin%2Fpolarportal%2Fsea%2FCICE_curve_thick_LA_EN_20200429.png&hash=8a74bfbcd95f79da43e49e65a2d61347)
Title: Re: The 2020 melting season
Post by: blumenkraft on April 30, 2020, 10:04:50 PM
We have liftoff north of Greenland, to the left of Nares

Sorry to nitpick, but north of Greenland is on the right of Nares (in the east). The picture is on the left of the Nares (to the west) and it's the CAA (Canadian Arctic Archipelago).
Title: Re: The 2020 melting season
Post by: F.Tnioli on April 30, 2020, 10:41:41 PM
Hmmm... 🤔
500 km3 of ice gone in last 10 days of April, eh. If this what's going on, then things melt as if it was last 10 days of May, not April. Like lengthening melt season by 1 month, sort of. For BoE, "extra 3 weeks" should suffice if one would do some silly numbers on a napkin based on what we saw in 2019. Could be we're starting to see even more melt power than anticipated per some above concerns, Pinatubo and all. Please keep 'em volume graphics coming if possible once a week. Few more weeks should tell us helluva lot of story already if this pace would continue.
Title: Re: The 2020 melting season
Post by: Phoenix on May 01, 2020, 01:03:33 AM
what's the difference between PIOMAS volume and DMI volume?
Title: Re: The 2020 melting season
Post by: Niall Dollard on May 01, 2020, 01:28:51 AM
what's the difference between PIOMAS volume and DMI volume?

Different models

PIOMAS http://psc.apl.uw.edu/research/projects/arctic-sea-ice-volume-anomaly/

DMI: http://ocean.dmi.dk/arctic/icethickness/icetext.uk.php



That's a big one slowly making its way down the Fram (~110 km wide)
Title: Re: The 2020 melting season
Post by: Freegrass on May 01, 2020, 01:51:58 AM
That's a big one slowly making its way down the Fram (~110 km wide)
That's been sitting there for almost 2 weeks now.
Translation: Fram export has been very slow lately.
Title: Re: The 2020 melting season
Post by: PragmaticAntithesis on May 01, 2020, 02:01:12 AM
<snip>
Fram export has been very slow.

Just about the first time we've heard that all year!
Title: Re: The 2020 melting season
Post by: Paul on May 01, 2020, 02:39:21 AM
what's the difference between PIOMAS volume and DMI volume?

No idea on that one but the theory between the differences between crysosat and PIOMAS is snowcover on the pack. Maybe the DMI model is similar although whenever I look at the DMI thicknesses graph, it does seem to look suspicious to me and other people.
Title: Re: The 2020 melting season
Post by: Wherestheice on May 01, 2020, 05:39:53 AM
If you look at the DMI and PIOMAS graphs for volume side by side, you'll notice that the PIOMAS graph shows volume dipping lower than DMI. I to am wondering why this is
Title: Re: The 2020 melting season
Post by: oren on May 01, 2020, 05:51:42 AM
I would ask that discussion of the DMI volume (based on Hycom-CICE model) and its comparison with PIOMAS and with actual measurement (Cryosat, SMOS) take place in a separate new thread - and not the existing one that compares PIOMAS vs. Cryosat.
The reason for that is I believe the DMI model is of less value than the other volume measures, and I don't want it to bog down this thread. Every year the same issues arise, and it would be good to have a separate thread discussing it. And who knows, we might suddenly discover that the DMI volume is of high value.
Until such comparison take place and some proof of value is found (or maybe there is an existing thread proving it? I can't recall), I ask that people don't make too many posts in this thread based on the DMI volume. It is okay to mention it and post charts from time to time but don't let it become the focus or cause too much clutter.
Title: Re: The 2020 melting season
Post by: bbr2315 on May 01, 2020, 09:25:30 AM
The 00z EURO would be catastrophic re: melt ponding.

This is the D5-10 anomaly average, but by D10 -- far out, I know -- the HP is pushing 1060MB. The 500MB blocking is insane.
<Please avoid posting forecasts more than 5 days out. O>
Title: Re: The 2020 melting season
Post by: Stephan on May 01, 2020, 10:26:13 AM
That's a big one slowly making its way down the Fram (~110 km wide)
This big floe consists of probably two-year or even multi-year sea ice?
Title: Re: The 2020 melting season
Post by: uniquorn on May 01, 2020, 12:18:09 PM
This is the D5-10 anomaly average, but by D10 -- far out, I know
<Please avoid posting forecasts more than 5 days out. O>
I'd be interested to see your longer term forecasts on Atmospheric connections, structure, and long range weather forecasting (https://forum.arctic-sea-ice.net/index.php/topic,2692.0.html)
Title: Re: The 2020 melting season
Post by: Freegrass on May 01, 2020, 02:03:18 PM
I can't remember seeing ice temperature being posted here before. It's amazing how much the ice has warmed up in the last month.


Click on the animation button below the image.
http://polarportal.dk/en/sea-ice-and-icebergs/sea-ice-temperature/ (http://polarportal.dk/en/sea-ice-and-icebergs/sea-ice-temperature/)
Title: Re: The 2020 melting season
Post by: Jim Hunt on May 01, 2020, 02:10:14 PM
what's the difference between PIOMAS volume and DMI volume?

Please see: https://forum.arctic-sea-ice.net/index.php/topic,3076.0.html
Title: Re: The 2020 melting season
Post by: Stephan on May 01, 2020, 02:12:36 PM
The ice temperatures in 2020 do not differ fundamentally from what has been observed the last years. I had a look athe DMI website (thank you for the link) and found that on May 1, 2019 the temperatures were even higher than this year. 2018 (and also 2014) was cooler, and for 2017 to 2015 I do not see a significant change from today's values. But this comparison is made by eye-balling. There are of course quantitative evaluations available.
Title: Re: The 2020 melting season
Post by: Freegrass on May 01, 2020, 03:03:49 PM
I don't think there's much to learn from ice temperatures, right? I was just amazed to see how much the temperature had changed during this last month. I don't think it'll matter much for the rest of the season.
Title: Re: The 2020 melting season
Post by: Richard Rathbone on May 01, 2020, 03:16:13 PM
what's the difference between PIOMAS volume and DMI volume?

DMI is an operational forecast model.
PIOMAS is a total volume measurement model.

They both model the same physics in much the same way, but they make different compromises because they are built to answer different questions.

Because the physics is the same they are each capable of doing the job the other one does, but they are likely to be worse at it.

If you want an operational forecast (what will the ice conditions be where I want to travel in the next couple of days) use DMI. If you want to know what the volume was in the past, use PIOMAS.

Some features of the physics (in particular the way the melting point changes with salinity) make the equations tricky to solve without numerical instabilities, and this particularly plagues the operational forecast models. Consequently they make rather more severe compromises with the physics than PIOMAS does and are fairly hopeless compared to PIOMAS when they step outside the narrow range of questions they are built to answer. PIOMAS crushes them in seasonal forecasting even though they are forecast models and PIOMAS is a measurement model.

Title: Re: The 2020 melting season
Post by: oren on May 01, 2020, 03:24:50 PM
RR, from now on please discuss DMI volume at the new thread linked by JH above, to which I copied your post.
Title: Re: The 2020 melting season
Post by: blumenkraft on May 01, 2020, 07:04:35 PM
Look at all that blue at the Atlantic side, right up to the north pole.

Could indicate wet snow/ice for how i understand it.
Title: Re: The 2020 melting season
Post by: blumenkraft on May 01, 2020, 07:15:38 PM
Also rather dark in M10 band, indicating wetness.
Title: Re: The 2020 melting season
Post by: Niall Dollard on May 01, 2020, 07:43:43 PM
We do have a research vessel located in that supposed "melt" area (The Polarstern).

Here is another image view from Univ Bremen and where Polarstern is currently located. Acoording to that Polarstern is in the yellow/green area which is much reduced concentration.

But unless we hear reports soon from Polarstern that they are sloshing about in melt ponds, I very much doubt that Bremen colorations are accurate.

As I type current temperature at Polarstern is -13 C. So I doubt there is much melting there yet. 
Title: Re: The 2020 melting season
Post by: blumenkraft on May 01, 2020, 08:00:01 PM
sloshing about in melt ponds.

I think (i hope) it's not that bad.

This 'wetness' could also mean that it's just very humid there at the ice surface. There are a lot of cracks, releasing heat from the seawater into the (still) cold air.
Title: Re: The 2020 melting season
Post by: Niall Dollard on May 01, 2020, 08:07:39 PM
There have been cracks in the area. But I cant see them releasing that much heat to affect the Bremen chart so much. Besides much of the leads will freeze over quite quickly.

The legend for the Bremen chart refers to ice concentration and yellow/green descends to 50% concentration.

This is clearly not true.
Title: Re: The 2020 melting season
Post by: blumenkraft on May 01, 2020, 08:10:08 PM
Niall, of course, it's not true.

But the sensors see something there. What is it in your opinion?
Title: Re: The 2020 melting season
Post by: bluice on May 01, 2020, 08:16:00 PM
Slater is predicting the ESS to melt out before the Laptev it seems. That would be interesting...

This is from Slater thread. Pls take a look at the picture.  Something odd seems to be going on there. The North Hole or just a sensor artifact?

Edit: couldn’t post the picture with phone. The pic on Freegrass’s post shows the ”Hole” between Svalbard and the Pole
Title: Re: The 2020 melting season
Post by: gerontocrat on May 01, 2020, 08:38:35 PM
Slater is predicting the ESS to melt out before the Laptev it seems. That would be interesting...

This is from Slater thread. Pls take a look at the picture.  Something odd seems to be going on there. The North Hole or just a sensor artifact?

Edit: couldn’t post the picture with phone. The pic on Freegrass’s post shows the ”Hole” between Svalbard and the Pole
The images from Bremen & NSIDC for 30 April show an awful lot of not-a-lot-of-ice from the pole to FJL / Svalbard
Title: Re: The 2020 melting season
Post by: HapHazard on May 01, 2020, 08:46:25 PM
So what is that, really? Cloud/storm tracks throwing off the data or something?

Are different data collectors getting this same result?

Don't we see this same sort of thing all the time in different areas, so this is unremarkable?

Title: Re: The 2020 melting season
Post by: gerontocrat on May 01, 2020, 09:01:24 PM
So what is that, really? Cloud/storm tracks throwing off the data or something?

Are different data collectors getting this same result?

Don't we see this same sort of thing all the time in different areas, so this is unremarkable?
If memory serves me right, melt ponds are the usual culprit for the sensors seeing open water where there is actually ice, but it is too early for melt ponding at such high latitudes.

It is also unusual for such a strong signal over such a wide area.

Scientists are always there when you don't want them, and when you do.......

& yes, Bremen uses data from the high res sensor with the big radar dish, NSIDC is using 1970/1980's technology.

& the JAXa thckness image shows dark green (= 1 metre thick ice which is thin) twixt the pole & FJL
Title: Re: The 2020 melting season
Post by: Freegrass on May 01, 2020, 09:10:12 PM
So what is that, really?
I think the ice got "stretched out" there last week. That created a lot of open water between the flows.
Title: Re: The 2020 melting season
Post by: blumenkraft on May 01, 2020, 09:12:14 PM
Re: Graying

Click to play. All years are first of May.
Title: Re: The 2020 melting season
Post by: oren on May 01, 2020, 09:17:30 PM
Niall, of course, it's not true.

But the sensors see something there. What is it in your opinion?
I expect these are transient weather artifacts. Animate it to get a better sense of it.
Title: Re: The 2020 melting season
Post by: blumenkraft on May 01, 2020, 09:25:22 PM
... Animate it ...

Here you go! :)
Title: Re: The 2020 melting season
Post by: Niall Dollard on May 01, 2020, 09:51:33 PM
Niall, of course, it's not true.

But the sensors see something there. What is it in your opinion?

I wonder is it cloud related ?

Just looking at the timing of the Terra Modis image for the 30th shows a band of cloud immediately to the north of Svalbard. In this area Bremen has a dark purple area. Further north of Svalbard Terra is clear and Bremen has much lower concentration.

But of course this happens often on any given day (the interplay of cloud and clear area).

Earlier in April we were questioning something similar over the Beaufort and general conclusion was that it was an artefact because of the sudden day to day movement.

I really don't know why.   
Title: Re: The 2020 melting season
Post by: blumenkraft on May 01, 2020, 09:57:46 PM
Me neither, Neill. ;) Perhaps it rained, perhaps moisture, perhaps clouds. Let's see if we hear something from the Polarstern.

Thanks for your answer.
Title: Re: The 2020 melting season
Post by: Freegrass on May 01, 2020, 10:23:37 PM
The five day forecast looks boring. But maybe boring is good for a change?
It looks like boring was good indeed. The temperature is back to normal, and the forecast stays "boring" for a few more days.
Title: Re: The 2020 melting season
Post by: grixm on May 01, 2020, 10:34:44 PM
JAXA thckness

Haven't seen this before, what can we find historical data and how is it calculated?
Title: Re: The 2020 melting season
Post by: F.Tnioli on May 01, 2020, 11:06:36 PM
Me neither, Neill. ;) Perhaps it rained, perhaps moisture, perhaps clouds. Let's see if we hear something from the Polarstern.
...
This photograph, i believe, was created from Polarstern's bridge ~3 days ago, 28th April:

(https://earthobservatory.nasa.gov/blogs/fromthefield/wp-content/uploads/sites/2/2020/04/photo3_sfons_20200423_small_web.jpg)

Can you see the bear? Anyhow, from the accompanying note posted at nasa.gov (https://earthobservatory.nasa.gov/blogs/fromthefield/2020/04/28/polar-bear-visits-polarstern/), we can read that the bear is, quote, "standing behind Met City near a small lead, likely waiting for a seal". Earlier in the note, we also read that bear, quote, "... sat near a small crack in the ice for almost two hours, likely waiting for a seal to surface".  Seals, i understand, would need open water to come onto the ice, where polar bears could hunt them. So, it seems there are some areas of open water per the above - and it looks like at least some of such openings do not freeze up any much for ~2 hours. I don't think bears are that stupid to spend some hour+ hunting a piece of any significantly thick ice, are they?

Much more importantly, however, is shape of sea ice which above picture presents. As one can see, ice in this particular area is abundantly uneven. With Sun being low over horizon for the time being, this creates really long shadows, clearly visible on the picture. Yet surfaces which are _creating_ those shadows - are often nearly vertical, and thus they absorb lots of sunlight. I think those surfaces are wet, - now that air is much cleaner than in previous melt season, very long path it takes sun rays to go through the athmosphere (because Sun is so low yet) does not deplete energy of sunlight anywhere close as it did previous seasons. Like was mentioned couple pages ago, one can easily see from Finland shore all the way to Estonia now - visibility is _times_ better. Same story would mean times higher W/m2 hitting those "bumps" on sea ice, per above picture - and wet them up good deal even while overall 2m tempeatures may be at -10C or even lower.

And we clearly see the area was quite well lit as of 3 days ago, too.

If someone has any better explanation than above, then please share.
Title: Re: The 2020 melting season
Post by: gerontocrat on May 01, 2020, 11:21:45 PM
JAXA thckness

Haven't seen this before, what can we find historical data and how is it calculated?
Standard JAXA provision @ https://ads.nipr.ac.jp/vishop.ver1/vishop-monitor.html?N
Several image choices.

Data goes back to 2002?

How calculated ? Beyond my pay grade. Ask Japan.
Title: Re: The 2020 melting season
Post by: Tigertown on May 02, 2020, 12:01:32 AM
So what is that, really?
I think the ice got "stretched out" there last week. That created a lot of open water between the flows.
The ice definetly got stretched out and not only allowed for open water but probably with this same movement caused upwelling. Anyone know the temperature in this area? Not the surface but just below it.
Title: Re: The 2020 melting season
Post by: johnm33 on May 02, 2020, 12:30:01 AM
'stretched' I agree the low though not powerful was huge and slowed the movement of water towards Fram if it was far enough away. If the water flowed back we should see an opening forming in Laptev soon, otherwise the stretching should continue for a couple of days. 
Local buoy https://www.whoi.edu/page.do?pid=165636
Title: Re: The 2020 melting season
Post by: S.Pansa on May 02, 2020, 07:16:10 AM
JAXA thckness

Haven't seen this before, what can we find historical data and how is it calculated?
I have no clue how he's doing it, but Wipneus has crunched the numbers.
Below the JAXA AMSR2 volume graph from 2012 onward (seems to be discontinued since 08-19), he has also thickness graphs on his site:
https://sites.google.com/site/arctischepinguin/home/sea-ice-extent-area/grf
Title: Re: The 2020 melting season
Post by: blumenkraft on May 02, 2020, 08:01:43 AM

Good read! Thanks, F.Tnioli.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 02, 2020, 08:13:54 AM
Those Bremen images are because of water vapor.  Frozen or not it messes with the scan of the ice.

It's why jaxa uses a lower scanning resolution

It's also why some big time scientists at Bremen or Hamburg(can't remember) have designed algorithms for a theoretical ice imaging satellite that incorporates all of the different channel frequencies in real time to offer a look at the sea ice that is no more than 95% Percent perfectly accurate with 5km resolution any time of the year.

As someone also said melt ponds cause that look as well but that's not happening this early.  Would need a miraculous warm air feed/ridge to get any of that.

But we're close.

The major global models all forecast the first ARCTIC DIPOLE ANOMALY OF THE SEASON.

We'll see it comes to fruition.  But this would bring warming sunshine into the 60-75N range of the Arctic.  Enough to start surface melting of some degree.

But even so it will be very weak and entirely preconditional in nature.

Does anyone have a reliable snow depth map of the Arctic basin?


Title: Re: The 2020 melting season
Post by: Aluminium on May 02, 2020, 09:37:33 AM
April 26 - May 1.

2019 (https://forum.arctic-sea-ice.net/index.php/topic,2591.msg197582.html#msg197582).
Title: Re: The 2020 melting season
Post by: Niall Dollard on May 02, 2020, 10:35:37 AM
Thanks for that F.Tnioli and Friv.

Later on in the season the Bremen images will become more trustworthy/useful as ice conc diminishes and especially useful at the edges.
Title: Re: The 2020 melting season
Post by: binntho on May 02, 2020, 12:44:08 PM
Can you see the bear? Anyhow, from the accompanying note posted at nasa.gov (https://earthobservatory.nasa.gov/blogs/fromthefield/2020/04/28/polar-bear-visits-polarstern/), we can read that the bear is, quote, "standing behind Met City near a small lead, likely waiting for a seal". Earlier in the note, we also read that bear, quote, "... sat near a small crack in the ice for almost two hours, likely waiting for a seal to surface".  Seals, i understand, would need open water to come onto the ice, where polar bears could hunt them.

Sometimes when you think something is general knowledge ... but apparently not. Seals nead to breathe. They maintain breathing holes in the ice. Polar bears seek out these breathing holes and wait patiently, up to several hours (often hiding their black snout with a small clump of ice). If the seal does take the change to stick it's nose up for a quick gulp of breath, the waiting polar bear clobbers it and draws it up onto the ice. Seals do NOT crawl onto the ice where polar bears "can hunt them"!

The seal creates breathing holes in the ice as it is forming in the fall, and can maintain them all winter with their paws, sometimes through as much as 2m of ice. But of course, once the ice starts moving and shifting, the seals probably get tempted to use the leads that open op in this way as well, maintaining a short-term breathing hole in a rapidly refreezing lead.

The polarstern people probably were seeing the latter, since they most certainly would have noticed the "aglus" or proper breathing holes if they had been in their vicinity.
Title: Re: The 2020 melting season
Post by: Freegrass on May 02, 2020, 01:11:30 PM
Five Day Forecast
Wind + Temp @ Surface
Title: Re: The 2020 melting season
Post by: F.Tnioli on May 02, 2020, 02:50:42 PM
... Seals do NOT crawl onto the ice where polar bears "can hunt them"!
...
They do, see v=zNO0kxTClYo on YT. However, i'm much more interested to know what you think about my above hypothesis of sunlight actually adding some melt water whenever irregular ice/snow surfaces are present. I agree with others when they say it'd be highly unusual to see melt ponds forming now, but then i also see highly (pun intended) unusual temperatures in March on Atlantic and Siberian sides, too:

(https://1.bp.blogspot.com/-7cc5WQWvTkI/XpwkOIWD9GI/AAAAAAAAbwo/-Sa5ubuggso8_Yd6kIfuhdpJgNAgEZRBgCLcBGAsYHQ/s1600/NASA.png)

I wish we could just ask good gents on Polarstern to go out and check if snow/ice is any wet when it's sunny around the ship. I know satellite sensors can pick up liquid water even when it's not in distinct ponds, but mixed with snow on top of ice. Could be one big part of those "strangely little ice" images posted above, me thinks.
Title: Re: The 2020 melting season
Post by: be cause on May 02, 2020, 07:28:44 PM
Hi F. Tnioli .. I have been raising a similar hypothesis here for some years .. low angle sun melting near vertical ice faces .. my thoughts were mostly relating to the exposed fracture surfaces as they seemed to increase in number over the years , Last year I was remarking on the obvious 360' melt and run-off on the steep slopes around an mini island ice sheet N of russia while the horizontal surface was unaffected . b.c.
Title: Re: The 2020 melting season
Post by: uniquorn on May 02, 2020, 10:17:11 PM
Here are the Meereisportal pre-packed charts from their (hopefully) currently active Mosaic snowbuoys (https://data.meereisportal.de/gallery/index_new.php?active-tab1=method&buoytype=SB&region=all&buoystate=active&expedition=MOSAiC&buoynode=all&submit3=display&lang=en_US&active-tab2=buoy) click to run

Also an ascat animation for this freezing/melting season so far. I dug out this quote from A-team explaining some of the reasons for light and dark colouration (which has been considerably enhanced. ImageJ, contrast minimum=41, clahe=127,256,5.3)
Quote
Ascat grays show near-surface ice salinity, ie upward brine extrusion. Ice Ih crystals (https://en.wikipedia.org/wiki/Ice_Ih) cannot accommodate any guest atoms, not even fluoride. The radar penetrates dry snow but beam reflection back to the satellite is diminished (darkening) by its surface dielectric constant (polarity of Na+ Cl- salts) escaping above and below through brine channels. In MYI, the brine exclusion process is near completion. MYI can be melted and drunk, unlike FYI or SYI (Borneo experience).

Thus whiteness on Ascat is closely correlated with increasing ice age which in turn is strongly correlated with ice thickness. That’s the reason cryo2smos (as panoply grayscale) looks so much like Ascat. There’s little value to summer Ascat because of airborne spray in liquid cloud aerosols and brine reforming in meltwater.
I would add that the whiteness in new ice seen along the ESS and Laptev coasts, and that appearing in new leads, is due to some reason other than old age. The mp4 is 5.5MB with no additional -crf compression
Title: Re: The 2020 melting season
Post by: oren on May 03, 2020, 09:31:58 AM
Also an ascat animation for this freezing/melting season so far.
I think I've replayed this more than 30 times. I am deeply concerned with the sustained ~month of west-to-east movement and export into the Fram. The movement pulls back the ice from almost as far as the Beaufort. This kind of movement could gut the Arctic of its most important ice, if it happens again and is sustained for longer. Not sure what kind of weather pattern can cause this and what the probability is for it to remain sustained for a long period.
The animation clearly shows that while Fram export continues throughout the freezing season, not all export is equal. Most of it comes from newish and thinninsh ice to the "left" of Svalbard and FJL. But during the said movement, the exported ice comes from thick ice between the Pole and Greenland. At the same time, a lot of thick ice also moves from this area to the region between the Pole and Svalbard, ready to be exported later. (This is shown in PIOMAS now as a region with very high volume). I tried to measure this movement. There is a small blackish circle halfway between the Nares entrance and the North Pole on day 68, having been there for a few weeks. Then suddenly it starts moving to the right, and ends close to the northeast tip of Greenland on day 105. I estimate the distance moved at 400-500 km. With the width of the moving front at around 400 km, and a thickness of around 3m, this would be ~200k km2 of area and 600 km3 of volume that were lost or are surely doomed, all of which is hard-to-melt ice that could resist and persist beyond September. All the above numbers are rough guesses.
I repeat an earlier post on the same subject, that air temps up or down a few degrees at this stage of the season are much less important than the movement of the ice, if sustained, and I will keep on hoping that the lull in export in recent weeks is continued.
Title: Re: The 2020 melting season
Post by: gandul on May 03, 2020, 03:08:19 PM
Current NH albedo is about normal overall. Spring is coming late over Canada.
Title: Re: The 2020 melting season
Post by: F.Tnioli on May 03, 2020, 03:14:55 PM
... Not sure what kind of weather pattern can cause this and what the probability is for it to remain sustained for a long period. ...
Why, we can see it alright. Quite a pattern indeed.

Day 68 is early March, and we had "positively persistent, persistently positive" AO at the time, as conviniently reported exactly in early March on this page (http://nsidc.org/arcticseaicenews/2020/03/a-positively-persistent-persistently-positive-arctic-oscillation/).

So i took a quick look and it seems we had up to some 25 km/h winds exactly "between Pole and Greenland" at day ~68, surface level:

(https://i.postimg.cc/j2SP5Lvm/25kmh.jpg)

Importantly, this was very wide wind field, as you can see. Looks like ~25% of CAB ice was pushed sough and then south-east by those winds, which push mounts to huge pressure, i'd imagine, given how large area this wind was working against. Which usually doesn't do much in winter because ice holds structurally. But i think this time, it snapped under the pressure near that day 68. It'd probably still remain mostly stuck, but ~4 days later, this started (and lasted for a few days):

(https://i.postimg.cc/XYzcVQnw/71kmh.jpg)

Given your numbers, which mean some ~0,5 km/h drift speed average for those 37 days, and given this wind speed - that drift does not surprise me the least.

I also checked same (or very close if no data for exactly March 8th is available) all the way back to 2014, and not a single year had anything similar even to 1st picture, normally it's smaller much more wavy winds much within CAB itself; and especially nothing even remotely close to the 2nd picture.

P.S. It was also then and there we had that massive ozone hole present. I read most stratospheric ozone was gone. The gas absorbs / traps IR really well, so when there is little of it and no sunlight to speak of, big temperature gradients form up. Ergo, stronger winds. Which we exactly see per above.
Title: Re: The 2020 melting season
Post by: oren on May 03, 2020, 06:06:50 PM
I want to correct my estimates above. The black circle moved 600km from day 68 to day 105 (red arrow to blue arrow). The width of the ice movement was about 650km-700km. Lacking geographical tools, I base this on eyeballing Ascat and using the known distance of 712km between the North Pole and Cape Morris Jesup (blue line).
So using my crude math, ice area in question was ~400,000km2, and volume was ~1000km3-1200km3, using average thickness of 2.5m-3m.
Notes:
* Not all of this area and volume was lost, some of it is now hanging off Svalbard, and with some very good luck could avoid its export fate.
* As the Arctic Ocean was still very cold during this time, I expect some of the lost volume and a lot of the lost area was recreated by freezing of opened leads during the "stretching" process.

So in essence thick ice was replace with thin ice, and other thick ice was relocated to a more vulnerable region. As the melting season should be enough to do away with thin ice, I see this as a potential for a lower September area result by 200k-300k km2, all other things being equal. Of course, such things happened in other years as well, it is well beyond my pay grade to try and quantify just the anomaly. But it's certainly not good, and bears watching should it recur.
Title: Re: The 2020 melting season
Post by: Freegrass on May 03, 2020, 07:37:08 PM
I will keep on hoping that the lull in export in recent weeks is continued.
Sad to inform you that Fram export will begin again in two days from now. I already planned to post a wind forecast about that, but I'll do it tomorrow, because I already posted a temp forecast just yesterday.
Title: Re: The 2020 melting season
Post by: blumenkraft on May 03, 2020, 07:42:53 PM
Meanwhile, let's look into what happened last week.

First, the ozone hole closed. Hence i didn't make a GIF. If someone wants it, let me know, i do have the pictures.

Here is the Fram export via SAR.
Title: Re: The 2020 melting season
Post by: blumenkraft on May 03, 2020, 07:43:40 PM
7-day hindsight mean temperature anomalies.
Title: Re: The 2020 melting season
Post by: blumenkraft on May 03, 2020, 07:44:10 PM
Ice drift map.
Title: Re: The 2020 melting season
Post by: uniquorn on May 03, 2020, 08:48:23 PM
The black circle moved 600km from day 68 to day 105
whoi itp116 (https://www.whoi.edu/page.do?pid=164836) tends to confirm your observations, though drifting from further north it possibly covered a larger distance of 691.2km from the beginning of day68 to end of day105
2020   68.00019   -54.9353  87.0807
2020  105.97934    -8.6480  83.0588
movable type haversine distance calculator (https://www.movable-type.co.uk/scripts/latlong.html)
Full drift path is inset.
Title: Re: The 2020 melting season
Post by: blumenkraft on May 03, 2020, 08:56:44 PM
Good ol' ITP116! Had a purpose after all!
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 04, 2020, 07:07:08 AM
Current NH albedo is about normal overall. Spring is coming late over Canada.

That's a pretty crude way of making a determination on albedo.

Things are about to rapidly change in the NW 1/3td of North America
Title: Re: The 2020 melting season
Post by: Phoenix on May 04, 2020, 07:10:11 AM
On the whole, the 2020 melt season has been pretty uneventful.

The latest JAXA extent #'s have 2020 in 5th place, closer to 14th place than 1st. The latest 5 day NSIDC area average is a slight net gain.

Fram / Barents export should be perking up again this week with a high pressure of ~ 1050 heading for Greenland and a low in the Kara, but the early season has been much cooler thus far than last year. 
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 04, 2020, 07:15:22 AM
The euro is going ham on the dipole but more importantly major ridging over the NW 1/3rd of NA bringing a huge influx of sunshine and huge WAA.

Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 04, 2020, 07:17:59 AM
On the whole, the 2020 melt season has been pretty uneventful.

The latest JAXA extent #'s have 2020 in 5th place, closer to 14th place than 1st. The latest 5 day NSIDC area average is a slight net gain.

Fram / Barents export should be perking up again this week with a high pressure of ~ 1050 heading for Greenland and a low in the Kara, but the early season has been much cooler thus far than last year.

It's pretty irrelevant.

We are a month away before any mass  melt ponding in the Arctic basin will even take place.

Title: Re: The 2020 melting season
Post by: F.Tnioli on May 04, 2020, 07:47:55 AM
2-3 weeks is what i expect, Friv. Not 1 month. Cleaner air, you know. Instruments confirm, overall Arctic.
Title: Re: The 2020 melting season
Post by: Phoenix on May 04, 2020, 08:01:26 AM

It's pretty irrelevant.

We are a month away before any mass  melt ponding in the Arctic basin will even take place.

2D ice measures in May are clearly relevant. They impact albedo and are providing a buffer against intrusion of warm Pacific water. We're 7 weeks from solstice. At this time last year we had substantial open water in the Beaufort Sea.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 04, 2020, 08:07:13 AM
2-3 weeks is what i expect, Friv. Not 1 month. Cleaner air, you know. Instruments confirm, overall Arctic.

I'm just going by the historic modis 3-6-7 images.

Not one year sees surface darkening over the Arctic basin until the first week of June at the earliest.

And most of the major melt season's don't see that until the 10th-20th.

The models are showing some favorable patterns going into mid May but we have seen that many times and the issue is while the mid levels 500-900MB scream warm sunshine the bad angled sun even with it shining all day takes so much time to start denting and lowering that silly high .75-.85 albedo.

We really need to see snow cover start to vanish earlier than it ever has on the modern records.

And we have seen the last decade see a wall being hit in spring snow melt which delays the advance of warm surface air and warm melted river water flooding parts of the basin.

The forecast is looking like 3-4 days or more soon of major sunshine with 3-6C 850mb temps taking over all of Northwest NA and a Southerly to SSW wind blowing over the Yukon and over Alaska downsloping into the Arctic.

And this is with major incoming insolation.

Insolation by the 10th will be blowing well over 400w/m2 really about 425w/m2 between 60-70N and yet it sure takes a while to melt that snow and warm up the ground and local lakes and rivers.


Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 04, 2020, 08:11:06 AM

It's pretty irrelevant.

We are a month away before any mass  melt ponding in the Arctic basin will even take place.

2D ice measures in May are clearly relevant. They impact albedo and are providing a buffer against intrusion of warm Pacific water. We're 7 weeks from solstice. At this time last year we had substantial open water in the Beaufort Sea.

Saying there was substantial open water in the Beaufort sea last year at this time is severely disingenuous.


Title: Re: The 2020 melting season
Post by: Jim Hunt on May 04, 2020, 08:31:38 AM
In case it's of interest to anybody else in here, I'm currently remotely attending an EGU session on "Citizen Science":

https://meetingorganizer.copernicus.org/EGU2020/displays/35918
Title: Re: The 2020 melting season
Post by: Phoenix on May 04, 2020, 08:40:48 AM

Saying there was substantial open water in the Beaufort sea last year at this time is severely disingenuous.

Maybe you should grab a dictionary and look up the definition of disingenuous.

I see a lot of open water near Utqiagvik in the image from last year and a significant amount of open water near between Banks Island and the Alaska coast that isn't present at this time this year.

We interpret the term "substantial" differently.

Title: Re: The 2020 melting season
Post by: Jim Hunt on May 04, 2020, 09:05:07 AM
I see a lot of open water near Utqiagvik in the image from last year and a significant amount of open water near between Banks Island and the Alaska coast that isn't present at this time this year.


The "open water near Utqiagvik" you refer to was in the Chukchi Sea using the usual definitions. Below is an "objective" view on historical Beaufort Sea ice area.

2016 was the year for early open water in the Beaufort Sea:

http://GreatWhiteCon.info/2016/04/the-beaufort-gyre-goes-into-overdrive/
Title: Re: The 2020 melting season
Post by: Phoenix on May 04, 2020, 09:20:52 AM
I see a lot of open water near Utqiagvik in the image from last year and a significant amount of open water near between Banks Island and the Alaska coast that isn't present at this time this year.


The "open water near Utqiagvik" you refer to was in the Chukchi Sea using the usual definitions. Below is an "objective" view on historical Beaufort Sea ice area.


Fair enough. I'll stand corrected. The point remains that there was a lot more open water on the Pacific side last year at this point.
Title: Re: The 2020 melting season
Post by: oren on May 04, 2020, 10:05:12 AM
And there was even more open water on thr Pacific side in 2016. But it's not the only thing that matters. The melting season in the High Arctic hasn't really begun yet, we will wait and see.
Title: Re: The 2020 melting season
Post by: gandul on May 04, 2020, 10:29:18 AM
Current NH albedo is about normal overall. Spring is coming late over Canada.

That's a pretty crude way of making a determination on albedo.

Things are about to rapidly change in the NW 1/3td of North America
It's a first order component of albedo, it's capable to self preserve, or self-accelerate its own reduction, and this Spring evolution matters in the Arctic Summer
Title: Re: The 2020 melting season
Post by: Paul on May 04, 2020, 01:24:35 PM
There was some open water on between the ice floes in the Beaufort sea this time last year and the ice did not look all that strong but even then, who would of thought we would see the large amount of true open water by the end of the month. If you go like for like then this year's ice there does look a little more robust but let's see what it looks like by May 11th after it experience a few days of warm off shore winds and the Beaufort Gyre kicked into gear.

One thing for sure, it does look like it's a dipole that could last a good while and perhaps the only saving grace is that it's not a further 3 to 4 weeks down the line but even so, at least at upper levels, the air could be quite warm.

Also note the strong low forecast for the Kara Sea again, be interesting how the ice responds to this storm, so plenty to look at that's for sure.
Title: Re: The 2020 melting season
Post by: Freegrass on May 04, 2020, 03:36:49 PM
Five Day Forecast
Wind @ Surface
Title: Re: The 2020 melting season
Post by: VeliAlbertKallio on May 04, 2020, 04:09:22 PM
Hi, I do not want to give wrong advise to government, what is the best estimate of sea ice situation looking now. Someone was citing very worrying JAXA numbers. Could someone clarify as I do not want to be alarmist. How much there will be ice left exactly. (Of course, we never know what is the exact.) Give me some suggestion what is the best to be expected from this summer how much ice is left?
Title: Re: The 2020 melting season
Post by: blumenkraft on May 04, 2020, 04:26:51 PM
How much there will be ice left exactly.

If you referring to the future, no one can possibly know.

Quote
I do not want to be alarmist.

I would go with historical volume charts [1]. If this is not alarming anyone, they are tone deaf anyway.

[1] https://sites.google.com/site/arctischepinguin/home/piomas
Title: Re: The 2020 melting season
Post by: oren on May 04, 2020, 05:35:51 PM
V.A.K, please refer such questions and discussions to the season predictions thread:
https://forum.arctic-sea-ice.net/index.php/topic,3072.0.html (https://forum.arctic-sea-ice.net/index.php/topic,3072.0.html)
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 04, 2020, 08:14:24 PM
 The 00z euro and 12z gem are straight filthy with the ridge they are showing coming to the NA side.

This will definitely decimate snow cover and really kick start thawing rivers that feed into the Arctic from the Yukon West

I don't know if it will have an impact on the surface of the ice in the Beaufort.

If it lasts as long with the Southerly warm sunny flow that the models show then yeah after a week of that we will see some albedo change.

But in the decade that I have followed this closely.

We have seen this time and time again before May 20th and Everytime no matter how vigorous the sun and WAA is the process is remarkably slow.

Until the land on the way to the arctic is cleared of snow warm surface advection is hard to come by.

Either through the air being modified towards freezing or there being a surface inversion.

I will say on the backside of a top down ridge from 300mb to the surface culminating in a sprawling 1035-1048MB HP won't be featuring a surface inversion with that kind of deep layer mixing and long fetch Southerly wind.

I attached the euro and gem at the peak of the ridge.

Obviously the gem and it's 1060+ mb hp is a joke.

But the euro does peak over 1050mb.

Title: Re: The 2020 melting season
Post by: Paul on May 04, 2020, 08:49:58 PM
Yep it's not really the temperature that causes the damage at this time of year, it's the winds and how persistent they are blowing in more or less the same direction, coupled with the Beaufort Gyre and I would bet heavily the Beaufort sea will look somewhat different by around the 11th.

It will be interesting too see the Chukchi sea ice also by then, suspect we may see more open water on the Alaskan side in particular by then also.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 04, 2020, 08:55:18 PM
Quote
Also it's currently 2F(-17C) at Barrow, Alaska(Utqiagvik)
The forecast calls for:

Today: Flurries before 2pm. Areas of freezing fog before 2pm. Cloudy, then gradually becoming mostly sunny, with a high near 16. East wind around 15 mph.

Tonight: Flurries after 2am. Areas of freezing fog after 2am. Mostly clear, then becoming mostly cloudy toward daybreak, with a low around 6. East wind 10 to 15 mph.

Tuesday: Flurries before 2pm. Areas of freezing fog before 2pm. Mostly cloudy, then gradually becoming sunny, with a high near 16. East wind around 10 mph.

Tuesday Night: Flurries after 2am. Areas of freezing fog after 2am. Mostly clear, then becoming mostly cloudy toward daybreak, with a low around 6. Northeast wind around 10 mph.

Wednesday: Flurries before 2pm. Areas of freezing fog before 2pm. Partly sunny, with a high near 15. East wind 10 to 15 mph.

Wednesday Night: Mostly clear, with a low around 6.

Thursday: Mostly sunny, with a high near 20.

Thursday Night: Partly cloudy, with a low around 10.

Friday: Mostly sunny, with a high near 26.

Friday Night: Partly cloudy, with a low around 14.

Saturday: Mostly sunny, with a high near 29.

Saturday Night: Partly cloudy, with a low around 16.

Sunday: Mostly sunny, with a high near 31.


Utqiagvik AK
 71.3°N 156.81°W (Elev. 0 ft)

Granted that might change later on to something a little warmer. The NWS is typically slow to modify forecasts after 96 hours towards more extremes until the models have a solid consensus under 5 days.


Anyways that's really freaking cold and I know that doesn't speak for the entire NA arctic ocean coast.

My point is wind fracturing of the ice hasn't really taken place in these areas yet.

Open water will appear within the next 7 days.  But it's not like it really matters at this point. 

By now we have learned that snow depth on the ice is everything then overall weather between the end of May and July 15th.

If we see the first two weeks of June start out with a sprawling text book DIPOLE ANOMALY centered on the Southern Canadian Basin, Beaufort sea, and Canadian archipelago 2020 will be right on par with the biggest melt years.

Although it's been what 8 years since we had a dominant June DIPOLE.

So boring...
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 04, 2020, 08:59:31 PM
Yep it's not really the temperature that causes the damage at this time of year, it's the winds and how persistent they are blowing in more or less the same direction, coupled with the Beaufort Gyre and I would bet heavily the Beaufort sea will look somewhat different by around the 11th.

It will be interesting too see the Chukchi sea ice also by then, suspect we may see more open water on the Alaskan side in particular by then also.

Exactly, especially if new ice production is over where the open water grows. 

Even tho the SSTs in that growing area of open water won't start to really warm up until we cross into June.

However the larger the open water area is the more quickly heat can gather to warm local atmosphere and hit the ice the side.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 04, 2020, 09:21:33 PM
Does anyone have any links to real time and historical data of the ice breakup on the Mackenzie river.

Looking back at last year things really took off after May 18th.

But that was quickly squandered in June on.

2007 and 2012 just had insane weather for ice melt.

Expecially 2007.

2007 was amazing.

Ice thickness/snow depth is the only reason 2007 isn't still the record.


Title: Re: The 2020 melting season
Post by: F.Tnioli on May 04, 2020, 09:23:26 PM
As if 1050+ is not enough to be one helluva big story, though. Especially for May. Lots of places would see it as highest-ever in well over a century of observations, like, for example, Iceland (https://en.wikipedia.org/wiki/List_of_atmospheric_pressure_records_in_Europe#Iceland_monthly_maximum_figures_for_atmospheric_pressure).
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 04, 2020, 09:34:00 PM
As if 1050+ is not enough to be one helluva big story, though. Especially for May. Lots of places would see it as highest-ever in well over a century of observations, like, for example, Iceland (https://en.wikipedia.org/wiki/List_of_atmospheric_pressure_records_in_Europe#Iceland_monthly_maximum_figures_for_atmospheric_pressure).

Even the euro is now predicting a peak over 1055mb.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 05, 2020, 07:05:39 AM
The models are now in very good agreement all the way out to day 7-10.

They are brutal for the ice. 

A straight SUPERLONG WIND FIELD running from Alaska/nw Canada to the North Atlantic.

Conditions will dramatically deteriorate by the 14-15th is this happens.

WILD
Title: Re: The 2020 melting season
Post by: jdallen on May 05, 2020, 07:15:52 AM
 
The 00z euro and 12z gem are straight filthy with the ridge they are showing coming to the NA side.

This will definitely decimate snow cover and really kick start thawing rivers that feed into the Arctic from the Yukon West
<snippage>
But the euro does peak over 1050mb.

How fast snow cover disappears is pretty crucial for both the change in albedo and the warm water it dumps into Arctic watersheds.  NA has been lagging behind.  This will catch it up a bit.

This is also going to pull a lot of cold air out of the CAB, to be replaced with warmth and moisture from the south, looks like.

But Day-yum!
Title: Re: The 2020 melting season
Post by: Jim Hunt on May 05, 2020, 08:58:29 AM
A straight SUPERLONG WIND FIELD running from Alaska/nw Canada to the North Atlantic.

WILD

Welcome back Friv!
Title: Re: The 2020 melting season
Post by: Aluminium on May 05, 2020, 11:11:20 AM
April 29 - May 4.

2019 (https://forum.arctic-sea-ice.net/index.php/topic,2591.msg197936.html#msg197936).
Title: Re: The 2020 melting season
Post by: ajouis on May 05, 2020, 12:21:44 PM
does anyone think the increasing open water lead in the bering strait is the incursion of a warm current? It looks that way, especially given the shape and speed, but it could just have been a weak area given it's almost dead centre.
Title: Re: The 2020 melting season
Post by: Freegrass on May 05, 2020, 03:19:14 PM
does anyone think the increasing open water lead in the bering strait is the incursion of a warm current? It looks that way, especially given the shape and speed, but it could just have been a weak area given it's almost dead centre.
That open water was created by wind and movement of the ice.
If the forecast holds, the Chukchi and Bering Seas will start to see positive temperatures at the end of the week.
Title: Re: The 2020 melting season
Post by: Aluminium on May 05, 2020, 03:42:03 PM
Forecasts constantly show a lot of heat from the Pacific side. It will begin in 4 days. In 2019, similar forecasts (https://forum.arctic-sea-ice.net/index.php/topic,2591.msg199598.html#msg199598) appeared 10-14 days later.
Title: Re: The 2020 melting season
Post by: The Walrus on May 05, 2020, 04:21:20 PM
The 00z euro and 12z gem are straight filthy with the ridge they are showing coming to the NA side.
This will definitely decimate snow cover and really kick start thawing rivers that feed into the Arctic from the Yukon West
<snippage>
But the euro does peak over 1050mb.

It does not appear so.  The jet stream is dipping very far south just east of the Rocky Mountains.  Consequently, the entire eastern half of North America will experience record-breaking cold this week, and snow is forecast for much of the northeast over the weekend.
Quote
How fast snow cover disappears is pretty crucial for both the change in albedo and the warm water it dumps into Arctic watersheds.  NA has been lagging behind.  This will catch it up a bit.

This is also going to pull a lot of cold air out of the CAB, to be replaced with warmth and moisture from the south, looks like.

But Day-yum!
Title: Re: The 2020 melting season
Post by: Phoenix on May 05, 2020, 07:03:23 PM
Forecasts constantly show a lot of heat from the Pacific side. It will begin in 4 days. In 2019, similar forecasts (https://forum.arctic-sea-ice.net/index.php/topic,2591.msg199598.html#msg199598) appeared 10-14 days later.

Fairbanks,AK has a forecast high in the mid 70's on Sunday. That's about 15F above average. Winds are forecast to push some of that heat across the Bering Strait into the Chukchi and ESS.

That's a top ice killer. Heat up the giant rocks (North America, Siberia) and blow the heat over the adjacent ice. Very reliable on the periphery, not so much on the CAB which is far away from the big rocks.

Title: Re: The 2020 melting season
Post by: jdallen on May 05, 2020, 09:48:16 PM
The 00z euro and 12z gem are straight filthy with the ridge they are showing coming to the NA side.
<snippage>

It does not appear so.  The jet stream is dipping very far south just east of the Rocky Mountains.  Consequently, the entire eastern half of North America will experience record-breaking cold this week, and snow is forecast for much of the northeast over the weekend.
Quote
<snippage>
That snow forecast is going to be highly transient and not material to what's happening north, except in so far as the cold air exiting the Arctic has made room for warmer air to invade it.

Deep cold breakouts this time of year, especially far south does no good for the Arctic.

I will agree that snow cover in NE Canada & the CAA won't be particularly hurt by this event.  However peripheral regions from the Yukon west to Eastern Siberia *will* be.
Title: Re: The 2020 melting season
Post by: Stephan on May 05, 2020, 09:53:56 PM
I was fascinated by the warm (almost hot) spell that is going to move to the Yamal Peninsula, Western Siberia, on the Kara Sea coast next week in Aluminium's gif.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 05, 2020, 11:04:05 PM
The 00z euro and 12z gem are straight filthy with the ridge they are showing coming to the NA side.
This will definitely decimate snow cover and really kick start thawing rivers that feed into the Arctic from the Yukon West
<snippage>
But the euro does peak over 1050mb.

It does not appear so.  The jet stream is dipping very far south just east of the Rocky Mountains.  Consequently, the entire eastern half of North America will experience record-breaking cold this week, and snow is forecast for much of the northeast over the weekend.
Quote
How fast snow cover disappears is pretty crucial for both the change in albedo and the warm water it dumps into Arctic watersheds.  NA has been lagging behind.  This will catch it up a bit.

This is also going to pull a lot of cold air out of the CAB, to be replaced with warmth and moisture from the south, looks like.

But Day-yum!

What does that have to do with the Arctic basin
Title: Re: The 2020 melting season
Post by: Niall Dollard on May 05, 2020, 11:49:57 PM
I hope the upcoming pre-conditioning is more like what this 12Z ECMWF run is suggesting (than the GFS). GFS has 2m temperatures going positive across a wide area of the Arctic Basin at the end of the run Aluminium posted.

ECMWF still delivers +ve values for the ESS and into the Laptev and slides the big high over to Russian side at the end of the run. See also the very warm surface temps (+20C) in western Siberia moving right up to the snowline.

Of course these forecasts are in the medium range, still over a week away. And may change yet good or bad. 
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 06, 2020, 12:14:20 AM
I hope the upcoming pre-conditioning is more like what this 12Z ECMWF run is suggesting (than the GFS). GFS has 2m temperatures going positive across a wide area of the Arctic Basin at the end of the run Aluminium posted.

ECMWF still delivers +ve values for the ESS and into the Laptev and slides the big high over to Russian side at the end of the run. See also the very warm surface temps (+20C) in western Siberia moving right up to the snowline.

Of course these forecasts are in the medium range, still over a week away. And may change yet good or bad.

Its really hard to say.

Also don't forget that this time of year there is large duirnal swings in temperature.

So 21z-03z will be the warmest of the NA side from East to West.

Like max temps around 21z closer to GIS and NW Alaska a little after 00z

And 6z-12z on the Russia side.

The GFS is probably overdone
Title: Re: The 2020 melting season
Post by: Paul on May 06, 2020, 12:34:12 AM
Whichever model you look at, a dipole pattern WILL occur and the ice in the Beaufort sea is going to move with help of the Beaufort Gyre. That is not in doubt.

The usual caveats will apply on just how strong the dipole will be and its duraction. There is more than good enough trends of perhaps a strong blocking high developing over the Arctic with winds being in a dipole position. It will be very interesting how the ice reacts to this type of pattern.
Title: Re: The 2020 melting season
Post by: Freegrass on May 06, 2020, 01:31:04 AM
It looks like last week has been good for the ice. Volume has increased again.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 06, 2020, 02:58:38 AM
Whichever model you look at, a dipole pattern WILL occur and the ice in the Beaufort sea is going to move with help of the Beaufort Gyre. That is not in doubt.

The usual caveats will apply on just how strong the dipole will be and its duraction. There is more than good enough trends of perhaps a strong blocking high developing over the Arctic with winds being in a dipole position. It will be very interesting how the ice reacts to this type of pattern.

Its definitely going to open up water somewhere on the Pacific side.

Probably around the Mackenzie Delta and Chuckchi.

It will also kick start some surface melt on the Pacific side and decimate snow cover over NA NW side
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 06, 2020, 07:22:16 AM
The 00Z gem and GFS are ridiculous with the WAA and ridging.

The 00z euro isn't out yet.
Title: Re: The 2020 melting season
Post by: F.Tnioli on May 06, 2020, 10:00:04 AM
It looks like last week has been good for the ice. Volume has increased again.
Great news! I think, next week won't have unusually rapid total volume drop yet, too. But after ~15th, can be another unprecedented drop, it seems. Aluminium says about those 10...14 days, few posts above. And of course this whole deal about high pressure, too. I checked some air temps and winds couple days ago over ice in southern Greenland, a bit above surface, and it was up to 10C moist air going over rather big area there, which while not extremely abnormal then and there in the past - is still significantly higher than in previous seasons. Etc.

One usual feature of most kinds of collapsing systems - is increased volatility. This rapid drop last week is unusual, and now this rebound is also unusual. Thus, i think maybe we'll get another unusual drop by the end of May, possibly ending the month below 20k km3 in DMI numbers. I wonder how much, exactly, this "collapsing system is more volatile than usual" could apply to sea ice / melting season, though.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 06, 2020, 10:02:30 AM
 00Z euro is pretty bad for the ice.

The warm air advection and sunny skies really gets going along the North American coast on the 8th/9th through at least the 15th.

I animated the 00z euro h5 heights/surface pressure graphic and the 850mb temp anomaly graphic.

The animations start at 48 hours to 240 hours in 24 hour increments.

On the temp graphic the red color indicates 10-12C+ anomalies.  The more neon bright reddish color is 12C+
The deep orange 8-10C+
The orange 6C+

A side note right now very strong WAA is pressing almost to the coast of the Kara.  So we will see river ice and snow cover quickly perish all the way to the coast in this area over the next 10 days as well.

The models are consistently showing a 3rd push of very warm air straight into the Arctic basin through the Kara in mid May.

2012 was a year that warmth hit the Kara region and Pacific/NA side in May.

Hmm..



Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 06, 2020, 10:31:24 AM
2007 might be a once a century or even lovey
Longer occurrence.

It was amazing

If we had that today we would have barely above 1 million in area/extent by the min
Title: Re: The 2020 melting season
Post by: Niall Dollard on May 06, 2020, 01:14:15 PM
Yeah, Summer 2007 had such a prolonged dipole.

We lost so much 2 year old ice and older that we never recovered.

It would be disastrous if that synoptic pattern was to be repeated.
Title: Re: The 2020 melting season
Post by: Freegrass on May 06, 2020, 01:26:05 PM
Five Day Forecast
Wind + Temp @ Surface
Title: Re: The 2020 melting season
Post by: be cause on May 06, 2020, 05:13:37 PM
funny .. all these free compulsory downloads just helped me run out of data again .. b.c.
Title: Re: The 2020 melting season
Post by: Richard Rathbone on May 06, 2020, 09:49:13 PM
It looks like last week has been good for the ice. Volume has increased again.

DMI volume is essentially useless for this sort of purpose. See the DMI thread for details of why it shouldn't be used in this way.
Title: Re: The 2020 melting season
Post by: Freegrass on May 06, 2020, 09:56:05 PM
It looks like last week has been good for the ice. Volume has increased again.

DMI volume is essentially useless for this sort of purpose. See the DMI thread for details of why it shouldn't be used in this way.
Maybe the data is useless, but is the trend as well? When DMI says the volume increased, shouldn't we take that as a fact?
Title: Re: The 2020 melting season
Post by: grixm on May 06, 2020, 10:09:24 PM
It looks like last week has been good for the ice. Volume has increased again.

DMI volume is essentially useless for this sort of purpose. See the DMI thread for details of why it shouldn't be used in this way.

I've read that thread but my takeaway is not that it's "useless" for this. If it shows the volume going down or up, there are good reasons for that. The input data for the model isn't just random noise, it's actual weather, meaning that if conditions for the ice is bad, it will show the volume going down, and if conditions are good, it will show the volume going up. The absolute historical values may not be as accurate as f.ex. PIOMAS due to different design goals, but it's still a working volume model and the trend should not be neglected.
Title: Re: The 2020 melting season
Post by: Phoenix on May 06, 2020, 10:38:02 PM
It looks like last week has been good for the ice. Volume has increased again.

DMI volume is essentially useless for this sort of purpose. See the DMI thread for details of why it shouldn't be used in this way.

I've read that thread but my takeaway is not that it's "useless" for this. If it shows the volume going down or up, there are good reasons for that. The input data for the model isn't just random noise, it's actual weather, meaning that if conditions for the ice is bad, it will show the volume going down, and if conditions are good, it will show the volume going down. The absolute historical values may not be as accurate as f.ex. PIOMAS due to different design goals, but it's still a working volume model and the trend should not be neglected.

If a sensor misreads water vapor in a low cloud as open water, it produces a faulty low reading of ice volume. A subsequent reading w/o the cloud might yield a correct measurement. If your trend has bad data to begin with and concludes with good data, you have a bad trend.

To get a good trend from bad data, you need the data to be equally bad at point A and point B.
Title: Re: The 2020 melting season
Post by: oren on May 06, 2020, 10:50:07 PM
I ask again: Please don't over-discuss the DMI volume here. It's not reliable enough, neither for past comparisons nor for trend detection. I don't mind the chart posted from time to time. If you have good evidence for its reliability, please post it in the DMI volume thread.
Title: Re: The 2020 melting season
Post by: Phoenix on May 06, 2020, 11:36:16 PM
I ask again: Please don't over-discuss the DMI volume here. It's not reliable enough, neither for past comparisons nor for trend detection. I don't mind the chart posted from time to time. If you have good evidence for its reliability, please post it in the DMI volume thread.

I disagree. If you are going to allow data to be posted which is well understood (by regs) to be unreliable, then it's important to allow it to be debunked so that less informed readers are not misled by assertions of its reliability. An uneducated lurker coming to this thread mid-stream would get the misleading impression that sea ice volume is currently at an all-time low for the date from the DMI chart.

The most elegant solution seems to involve not posting DMI volume charts in this thread.

Title: Re: The 2020 melting season
Post by: Freegrass on May 07, 2020, 02:20:41 AM
I though it was interesting, and probably rare, that the temperature these days would still follow the long term average for a while... And then I looked at 2016...

Graphs are 2016, 2020, and 2019
Title: Re: The 2020 melting season
Post by: oren on May 07, 2020, 03:12:02 AM
I ask again: Please don't over-discuss the DMI volume here. It's not reliable enough, neither for past comparisons nor for trend detection. I don't mind the chart posted from time to time. If you have good evidence for its reliability, please post it in the DMI volume thread.

I disagree. If you are going to allow data to be posted which is well understood (by regs) to be unreliable, then it's important to allow it to be debunked so that less informed readers are not misled by assertions of its reliability. An uneducated lurker coming to this thread mid-stream would get the misleading impression that sea ice volume is currently at an all-time low for the date from the DMI chart.

The most elegant solution seems to involve not posting DMI volume charts in this thread.
And yet, this is my policy: posting the chart is allowed, over-discussing it is discouraged, debunking it (using detailed arguments) is encouraged - in the appropriate thread, which I hope to do myself when I find the time and ability. Yes it is unreliable, no, it is not totally devoid of value, until someone can prove that - in the appropriate thread. Policy disagreements are allowed - in the appropriate thread.
Title: Re: The 2020 melting season
Post by: Phoenix on May 07, 2020, 05:20:36 AM
For the benefit of any lurkers, here's a link to the UW PIOMAS volume thread. Per Gerontocrat's calculations, current sea ice thickness is greater than it has been since 2003 at this point in the UW indicates volume as being in 6th place all time,with 8.9% more ice than at this time in 2017.

https://forum.arctic-sea-ice.net/index.php/topic,119.3250.html
Title: Re: The 2020 melting season
Post by: El Cid on May 07, 2020, 07:58:37 AM
I though it was interesting, and probably rare, that the temperature these days would still follow the long term average for a while... And then I looked at 2016...

Summer temps are ALWAYS on the long term average (kept there by melting ice which pegs them to zero C despite heavy sun). Some even say that the definition of a BOE should/will be when summer temps go above the averages (basically around 273 K)
Title: Re: The 2020 melting season
Post by: Niall Dollard on May 07, 2020, 01:12:16 PM
Melt Pond Fraction of sea ice for next Monday 11th. Some ponding begins in the Chukchi.

Plot provided by the NOAA/ESRL Physical Sciences Laboratory, Boulder, CO from their Web site at https://psl.noaa.gov/

This is taken from the last image (+168hrs) from an old run (initial date 4th May). But I have n't seen a later run, yet.
Title: Re: The 2020 melting season
Post by: grixm on May 07, 2020, 09:48:05 PM
12z Euro
Title: Re: The 2020 melting season
Post by: FishOutofWater on May 07, 2020, 10:04:50 PM
There's a large heat anomaly building over the Pacific side of the Arctic ocean starting now. It may be linked to the pretty strong end warming in the stratosphere. The Arctic oscillation is reversing from cyclonic to anticyclonic as a large scale pattern of subsidence develops on the Pacific side of the Arctic ocean.

Meanwhile very cold air for this time of year is being driven out of the Arctic in my direction on the east coast of the U.S. This warm Arctic cold eastern North America pattern has happened in recent years with relatively strong end warmings.
Title: Re: The 2020 melting season
Post by: Phoenix on May 08, 2020, 02:38:45 AM
Truly some exceptional regional melting conditions in the coming days.

The forecast for the massive high pressure system is holding up and the Euro model has it peaking at 1055+ over Victoria Island in the Western CAA. At the same time, there is a low bottoming out at 965 in the Bering Sea adjacent to Siberia. That's an exceptional pressure differential. In between, there are temperatures well above average in Alaska.

That pressure differential and the migration of the low into Siberia is going to facilitate the transport of that Alaskan heat across the Chukchi and well into the ESS. The caveat is that this looks like a short duration event lasting a few days.

The Bering Sea will see sustained heat influx and we should see a rapid decline there in the data thread in the coming weeks.

In the big picture of the Arctic melting season, this is a high intensity, short duration event aimed at the periphery (south of 80N) of the Arctic. The CAB is in much better shape than most recent years as you can see from Oren's recent PIOMAS posting. It's going to take sustained intense melting / transports conditions to make a serious dent in the CAB this year.

Title: Re: The 2020 melting season
Post by: Bruce Steele on May 08, 2020, 02:46:45 AM
Fish out of water, Good to see you back for the melt season.
Title: Re: The 2020 melting season
Post by: Aluminium on May 08, 2020, 09:07:05 AM
May 2-7.

2019 (https://forum.arctic-sea-ice.net/index.php/topic,2591.msg198338.html#msg198338).
Title: Re: The 2020 melting season
Post by: Jim Hunt on May 08, 2020, 11:41:33 AM
For the benefit of any lurkers....

here's the latest CryoSat-2/SMOS "measured" volume:

http://GreatWhiteCon.info/2020/05/facts-about-the-arctic-in-may-2020/

The graph stops in mid April, since melt ponds confuse the sensors
Title: Re: The 2020 melting season
Post by: Jim Hunt on May 08, 2020, 11:44:20 AM
Fish out of water, Good to see you back for the melt season.

Hear, hear!
Title: Re: The 2020 melting season
Post by: Freegrass on May 08, 2020, 01:48:33 PM
Five Day Forecast
Wind + Temp @ Surface

My apologies to the people with low bandwidth, but this weather event is too big to ignore. There's a lot of ice that's gonna go down the drain in the coming week...
Title: Re: The 2020 melting season
Post by: Burnrate on May 08, 2020, 04:33:57 PM
Five Day Forecast
Wind + Temp @ Surface

My apologies to the people with low bandwidth, but this weather event is too big to ignore. There's a lot of ice that's gonna go down the drain in the coming week...

Are you talking about the big warm cyclone coming off of Norway on the 12th?  The strong consistent southerly wind in the Fram Strait?  Or am I totally missing the point?
Title: Re: The 2020 melting season
Post by: Freegrass on May 08, 2020, 04:45:56 PM
Five Day Forecast
Wind + Temp @ Surface

My apologies to the people with low bandwidth, but this weather event is too big to ignore. There's a lot of ice that's gonna go down the drain in the coming week...

Are you talking about the big warm cyclone coming off of Norway on the 12th?  The strong consistent southerly wind in the Fram Strait?  Or am I totally missing the point?
There's a lot going on in the Arctic right now. You have the high pressure system bringing in heat on the pacific side that will spread over the CAB, and you've got strong winds blowing ice out of the Fram and towards the Barents sea.

I'll post another wind update on the Nullschool Forecast thread later. It's really crazy the winds that are predicted.
Title: Re: The 2020 melting season
Post by: Burnrate on May 08, 2020, 04:54:05 PM
....

It's really crazy the winds that are predicted.

It does seem pretty volatile.  Can anyone comment on how this compares to previous years?  I'm no expert and don't post much but have been reading the blog for almost ten years :).

I've read about how the reduction in aerosols is supposed to create much more dynamic weather in the arctic in the short term.  It will be interesting to see how well we can link that reduction to increased temps/precipitation/storms this season.

This season is going to be a nail biter.
Title: Re: The 2020 melting season
Post by: F.Tnioli on May 08, 2020, 04:54:31 PM
here's the latest CryoSat-2/SMOS "measured" volume:

http://GreatWhiteCon.info/2020/05/facts-about-the-arctic-in-may-2020/

The graph stops in mid April, since melt ponds confuse the sensors
The figure's interesting to see alright, thanks for sharing! But here's one side note about it.

What melt ponds? Like was said above in the topic, there are no significant melt ponds in April in Arctic. Or were there? So, it sure looks like someone's lying: either those who said "no meltponds there", or whomever said "after mid-April melt ponds confused the sensors". Simple, right?

My guts say, it ain't melt ponds. DMI shows major volume drop in volume exactly in 2nd half of April. "Coincedence"? Hardly. And may i remind us all that DMI volume is "based on calculations using DMI's operational ocean and sea ice model HYCOM-CICE". Models don't get confused by melt ponds, eh. But people who see sensors showing volume going down when it shouldn't be going down even half as much - they have a reason to worry whether sensors are malfunctioning (or something gone wrong between sensors and actual collected data), and thus just make up an excuse and stop sharing data. Since they could be affraid at the time that collected data could be significantly wrong due to some technical malfunction or somesuch.

P.S. By the way, as of today DMI volume starts to dip down again. Already. Maybe CryoSat-2 now sees things which are way too wild to publish and the actual reason is not mainly about "melt ponds confuses sensors"? Confusions like this can sure happen aplenty when unexpected occurs. Please, let us try to find even more ways to estimate what's going on, gentlemen. It'd help.
Title: Re: The 2020 melting season
Post by: oren on May 08, 2020, 05:08:43 PM
F. Tnioli, a gentle warning: I will not tolerate hints of lies, conspiracies and the like on this thread. There is a perfectly good explanation, and lying by ice scientists is not it.
In addition, I've requested that DMI volume discussions take place in the appropriate thread.
Title: Re: The 2020 melting season
Post by: F.Tnioli on May 08, 2020, 05:53:27 PM
F. Tnioli, a gentle warning: I will not tolerate hints of lies, conspiracies and the like on this thread. There is a perfectly good explanation, and lying by ice scientists is not it.
In addition, I've requested that DMI volume discussions take place in the appropriate thread.
Will you tolerate this thread saying "there are no melt ponds in April" and also saying "no data from CryoSat-2 for 2nd half of April because meltponds confuse sensors"?

If the answer is "yes", i'll see myself to the door voluntarily. If the answer is "no", then i ask to forgive me for probably inappropriate way used to describe the problem.

DMI's realiability or lack of - was not discussed. I merely mentioned couple things about it as relevant to discussing "melt ponds in late April confused CryoSat-2 sensors" line, which line is the thing i discussed. DMI graphs are welcomed here for what - to ignore them? I am confused. For now i'll simply avoid doing _any_ mention of DMI results / data, then.

In any case, please feel free to snip this and/or previous post of mine any way you deem good for this topic, up to and including complete removal. I will never hold any grudge towards you, Oren, no matter how much my opinion may differ from yours at times.
Title: Re: The 2020 melting season
Post by: Wildcatter on May 08, 2020, 06:47:33 PM
Looking at the nasa over the last few days, aluminums gif, and the forecast. ESS might look pretty interesting in a week, might get punished for not eating its vegetables this winter (volume), more cracking with wind and ice movement.

could have cracking all around the "shell" (coasts), like the beaufort ones with continued southerlies. kara. the anti-cyclonic winds also seem to help spur ice retreat in the bering. FJL ice on the Atlantic side too, that one will probably close up but there's a lot of wind forcing and it's moved quite a bit just the last few days, then the big ol' cyclone comes in over the barents, good chunk of volume sitting next to it and svalbard

east eurasia heat might be worth watching, looks like its tired of being cold. and then all the fram/atlantic export, will be an interesting week
Title: Re: The 2020 melting season
Post by: shendric on May 08, 2020, 08:24:06 PM
Will you tolerate this thread saying "there are no melt ponds in April" and also saying "no data from CryoSat-2 for 2nd half of April because meltponds confuse sensors"?

There are two separate issues here as the CryoSat-2/SMOS thickness/volume is based on two different sensor types.

CryoSat-2 (radar altimetry): It is common practice to not compute thickness in the Arctic beyond April, since the snow will get wet in May which causes extinction of the radar waves. Open melt ponds that form later are a different issue.

SMOS (L-Band radiometry): Here, the method of thin-ice thickness estimation is based (in essence) on the temperatur difference between the sea water and the ice surface. And this difference can get too small at already in the end of April for reliable ice thickness estimates.

Thus, CryoSat-2 thicknesses stop at April 30 and SMOS (respectively CryoSat-2/SMOS) thicknesses stop at April 15.

Cheers, Stefan
Title: Re: The 2020 melting season
Post by: Phoenix on May 08, 2020, 08:51:03 PM
You have the high pressure system bringing in heat on the pacific side that will spread over the CAB, and you've got strong winds blowing ice out of the Fram and towards the Barents sea.

 It's really crazy the winds that are predicted.

Heat from the Pacific spreading over the CAB in early May would be a rare observation. What's your source for this and how are you defining the CAB?

Instead of using adjectives like "crazy" to describe the winds, maybe you can try objective descriptions like location, duration and wind speed so people have a better idea what you are referring to?
Title: Re: The 2020 melting season
Post by: Freegrass on May 08, 2020, 09:16:44 PM
You have the high pressure system bringing in heat on the pacific side that will spread over the CAB, and you've got strong winds blowing ice out of the Fram and towards the Barents sea.

 It's really crazy the winds that are predicted.

Heat from the Pacific spreading over the CAB in early May would be a rare observation. What's your source for this and how are you defining the CAB?

Instead of using adjectives like "crazy" to describe the winds, maybe you can try objective descriptions like location, duration and wind speed so people have a better idea what you are referring to?
I think the video is self-explanatory. If you want more details, you can always look those up on Nullschool.

https://earth.nullschool.net/#2020/05/12/1800Z/wind/surface/level/orthographic=-45.02,91.24,2304/loc=34.948,80.486 (https://earth.nullschool.net/#2020/05/12/1800Z/wind/surface/level/orthographic=-45.02,91.24,2304/loc=34.948,80.486)
Title: Re: The 2020 melting season
Post by: grixm on May 08, 2020, 09:41:59 PM
Strong Fram export in the last few days. Meanwhile the ice n the other side of Svalbard is retreating back towards the north.
Title: Re: The 2020 melting season
Post by: F.Tnioli on May 08, 2020, 09:42:54 PM
...
Thus, CryoSat-2 thicknesses stop at April 30 and SMOS (respectively CryoSat-2/SMOS) thicknesses stop at April 15.

No.

(https://i.postimg.cc/W4pnwrSk/SMOS.jpg)

Title: Re: The 2020 melting season
Post by: Phoenix on May 08, 2020, 10:17:03 PM
You have the high pressure system bringing in heat on the pacific side that will spread over the CAB, and you've got strong winds blowing ice out of the Fram and towards the Barents sea.

 It's really crazy the winds that are predicted.

Heat from the Pacific spreading over the CAB in early May would be a rare observation. What's your source for this and how are you defining the CAB?

Instead of using adjectives like "crazy" to describe the winds, maybe you can try objective descriptions like location, duration and wind speed so people have a better idea what you are referring to?
I think the video is self-explanatory. If you want more details, you can always look those up on Nullschool.

https://earth.nullschool.net/#2020/05/12/1800Z/wind/surface/level/orthographic=-45.02,91.24,2304/loc=34.948,80.486 (https://earth.nullschool.net/#2020/05/12/1800Z/wind/surface/level/orthographic=-45.02,91.24,2304/loc=34.948,80.486)

That link is a good example of data that helps people understand what you are referring to regarding "crazy" wind.

The link doesn't support your assertion that heat from the Pacific is going to spread over the CAB. What's the source for that?
Title: Re: The 2020 melting season
Post by: uniquorn on May 08, 2020, 10:30:07 PM
...
Thus, CryoSat-2 thicknesses stop at April 30 and SMOS (respectively CryoSat-2/SMOS) thicknesses stop at April 15.
No.
Please read....https://seaice.uni-bremen.de/thin-ice-thickness/
Quote
Thin sea ice occurs during the freezing season. In the melting season, the thickness of sea ice is highly variable and the emission properties in the microwave change due to the wetness of the surface and occurrence of melt ponds in the Arctic. Therefore, thickness data are calculated only during the freezing season, that is from October to April in the Arctic and from March to September in the Antarctic. During the melting season, the procedure does not yield meaningful results.
uni-bremen are kind enough to continue to provide the service as other information may be inferred from the data...at the user's discretion
Title: Re: The 2020 melting season
Post by: shendric on May 08, 2020, 10:38:20 PM
...
Thus, CryoSat-2 thicknesses stop at April 30 and SMOS (respectively CryoSat-2/SMOS) thicknesses stop at April 15.

No.

(https://i.postimg.cc/W4pnwrSk/SMOS.jpg)

The SMOS product (ex University Hamburg, now AWI) that goes into CryoSat-2/SMOS stops at April 15.
Title: Re: The 2020 melting season
Post by: Neven on May 08, 2020, 11:31:12 PM
Quote
Instead of using adjectives like "crazy" to describe the winds

By all means, use adjectives like "crazy" to describe winds and other phenomena. In fact, be as creative as you can (friv is a good teacher  ;) ). However, make sure that the forecasted winds truly are crazy, and a bit of comparative context is always nice.
Title: Re: The 2020 melting season
Post by: Freegrass on May 08, 2020, 11:56:53 PM
Quote
Instead of using adjectives like "crazy" to describe the winds

By all means, use adjectives like "crazy" to describe winds and other phenomena. In fact, be as creative as you can (friv is a good teacher  ;) ). However, make sure that the forecasted winds truly are crazy, and a bit of comparative context is always nice.
Thanks Neven.  :)  I'll keep doing my best to be better. But still so much to learn...  :-[

I'll be posting a new video with those "crazy winds" in an hour or so on the Nullschool thread, after Nullschool gets updated with the new GFS data. Then people will be able to see what I meant with crazy. What's coming is going to be so bad for the ice... But I like to let my video's speak for themselves... What is it they say about a picture and a thousand words?  ;)
Title: Re: The 2020 melting season
Post by: gerontocrat on May 09, 2020, 12:26:18 AM
winds & WARMTH
Title: Re: The 2020 melting season
Post by: F.Tnioli on May 09, 2020, 12:28:07 AM
...
uni-bremen are kind enough to continue to provide the service as other information may be inferred from the data...at the user's discretion
"Service" from "stopped" SMOS?

This is a recurring problem of this page: terms. "SMOS stopped" does not equal "does not produce meaningful results". "Other information may be inferred" does not equal "does not produce meaningful information". "Melt ponds confuse sensors" does not equal "wetness of the surface confuses sensors".

Since we're talking about, i'll note that from what i know, SMOS growing error in April has little to nothing to do with "melt ponds" nor with "wetness" of ice surface itself. Instead, the main problem is increasing presense of fog and thin clouds [Yu and Rothrock 1996]. This does not mean April and May SMOS data is "meaningless", however. It means different, more complex approaches are needed in treating raw data to have still useful and precise enough results. Specific data products having a cut at April 15 do not nesessarily mean all data products are stopped. The picture i gave as an example - is a kind of a data product itself, and is indeed useful for easy eye-balling of thin ice right now, in May.

Please note, i am not asking to explain every little detail in this topic. I ask to use non-contradicting terms. Like, instead of "melt ponds confuse sensors" - say, for example, "technology limitations disallow reliable total Arctic ice volume measurement after mid-April based on those sensors". Like, instead of "SMOS stopped" say "SMOS measurements stop being used for calculating total ice volume mid-spring due to growing measurement errors which currently we're unable to remove". Etc.

If we'd be failing to avoid "contradicting per common sense of a non-scientist" statements here - even when such contradictions are in error de-facto - then what exactly this topic is for?
Title: Re: The 2020 melting season
Post by: be cause on May 09, 2020, 12:54:01 AM
Really unusual is the near permanent ridge from Ireland to Alaska/Bering/Siberia .. ECM and GFS have it forecast to last the next 10 days .

  Oh .. And the wind , and the heat , the highs and the lows , the ejection of cold and it's consequences further south ...

 Welcome to the new May .. b.c.
Title: Re: The 2020 melting season
Post by: uniquorn on May 09, 2020, 01:07:57 AM
...
uni-bremen are kind enough to continue to provide the service as other information may be inferred from the data...at the user's discretion
"Service" from "stopped" SMOS?
>>>>>
If we'd be failing to avoid "contradicting per common sense of a non-scientist" statements here - even when such contradictions are in error de-facto - then what exactly this topic is for?
Hamburg, Bremen and AWI are different institutions. We are fortunate that we can share some of their data. We are unfortunate in that some of it disappears quite suddenly. I recommend using what you can while it is available. There is also this thread (https://forum.arctic-sea-ice.net/index.php/topic,2341.0.html)
edit:time for hyperion2??
Title: Re: The 2020 melting season
Post by: oren on May 09, 2020, 01:13:18 AM
Quote
Please note, i am not asking to explain every little detail in this topic. I ask to use non-contradicting terms. Like, instead of "melt ponds confuse sensors" - say, for example, "technology limitations disallow reliable total Arctic ice volume measurement after mid-April based on those sensors". Like, instead of "SMOS stopped" say "SMOS measurements stop being used for calculating total ice volume mid-spring due to growing measurement errors which currently we're unable to remove". Etc.

If we'd be failing to avoid "contradicting per common sense of a non-scientist" statements here - even when such contradictions are in error de-facto - then what exactly this topic is for?
Thank you for the better description of SMOS cutoff for Cryosat, and other SMOS limitations. This is what should have been posted in the first place if you find the original poster was not accurate enough. Clarify, explain, bring more info, make better wording. And do not hint the cutoff is to hide something or that somebody was lying because they used inaccurate terminology.

Back to what this topic is for - bringing information, data, analysis and commentary about the Arctic sea ice melting season that is just beginning in earnest.
Title: Re: The 2020 melting season
Post by: Phoenix on May 09, 2020, 03:30:41 AM
Siberia is heating up. Temps (C)in the mid twenties in the region just S of the Kara Sea.. This is your likely source of the heat coming through the Kara/Laptev into the Arctic in the coming days. Aided and abetted by the massive high pressure system over the Arctic and a couple of cyclones.

https://weather.com/en-TT/weather/tenday/l/ae0195f293190f0a3c83e846a147a91ec8935cd4be8021cb5e46b71ea2c6c5f3



Title: Re: The 2020 melting season
Post by: Phoenix on May 09, 2020, 04:55:01 AM
For those marveling at the intense high pressure system evolving in the Arctic at 1055+, there was a more intense high just last month in Nunavut that approached 1070.

https://www.theweathernetwork.com/ca/news/article/staggeringly-strong-high-pressure-in-nunavut-flaunts-record-values
Title: Re: The 2020 melting season
Post by: F.Tnioli on May 09, 2020, 05:03:41 AM
Thank you for the better description of SMOS cutoff for Cryosat, and other SMOS limitations. This is what should have been posted in the first place if you find the original poster was not accurate enough. Clarify, explain, bring more info, make better wording. And do not hint the cutoff is to hide something or that somebody was lying because they used inaccurate terminology.

Back to what this topic is for - bringing information, data, analysis and commentary about the Arctic sea ice melting season that is just beginning in earnest.
When it seems someone is not accurate enough, i exactly offer a description which i deem better one. Like i just did above, - and there is no need to thank me for it really, such a small thing. "Not accurate enough" at some point gets "so off the target it doesn't look they are even trying" though.

I see it's time i walk outta that door - stay silent at least for fairly long while. Especially seeing you saying i anyhow stated that "someone's lying because they used inaccurate terminology". Which, i never did. Nothing even remotely close. I take this as a gentle hint that it's time i say good bye - what else can it be, seeing it's from you, not some stranger.

I'll keep reading now and then and of course, i wish you best of luck keeping things orderly and neat. Cheers!
Title: Re: The 2020 melting season
Post by: oren on May 09, 2020, 08:23:15 AM
F. Tnioli, I hope you continue posting (staying within the guidelines of course) as you are a longtime contributor with often unique perspective.
Title: Re: The 2020 melting season
Post by: blumenkraft on May 09, 2020, 09:49:02 AM
I take this as a gentle hint that it's time i say good bye

I don't read that anywhere, FT.

I too hope you stay with us.
Title: Re: The 2020 melting season
Post by: gerontocrat on May 09, 2020, 11:26:22 AM
The first significant warming event in this melting season unfolds?
Title: Re: The 2020 melting season
Post by: Jim Hunt on May 09, 2020, 11:32:10 AM
Please note, i am not asking to explain every little detail in this topic. I ask to use non-contradicting terms. Like, instead of "melt ponds confuse sensors" - say, for example, "technology limitations disallow reliable total Arctic ice volume measurement after mid-April based on those sensors".

More haste less speed! Thanks for the clarification Stefan.

In case nobody's noticed I'm spending far more time on Covid-19 issues rather than sea ice at the moment.

I first typed "surface melt", then I thought I'd change it to "melt ponds" because that would convey the basic concept more easily in here. My bad!

Please bear in mind the current CS2/PIOMAS "anomaly" when discussing volume/thickness. As the latest PSC update (http://psc.apl.uw.edu/research/projects/arctic-sea-ice-volume-anomaly/) puts it:

Quote
April  ice thickness anomalies from PIOMAS agree well with the multi-sensor CryoSat/SMOS thickness analysis from the Alfred Wegener Institute/ESA with the strongest positive and negative anomalies in the right places. An area of thicker than normal ice  north of Greenland that was present in PIOMAS but missing from CryoSat/SMOS in March is now is now showing up in Cryosat/SMOS though considerably smoothed out.   The time series for CryoSat/SMOS  total volume shows  April 2020 as lower relative to the  2011-2020 period while PIOMAS shows a bit of an uptick. Neither time series indicates a trend over the past 10 years contrasting the drastic thinning over the last 40-years.  Note that Cryosat/SMOS retrievals only go through April 15 as the microwave based retrieval of both system forces a summer hiatus.

TTFN: http://CoV-eHealth.org/2020/04/30/covid-19-testing-in-the-uk/

This has been a public service announcement.
Title: Re: The 2020 melting season
Post by: Aluminium on May 09, 2020, 11:47:34 AM
The forecast from 18.05.2019 is added for comparison. The melting season is going to lift off. The next stop is hell.

(https://forum.arctic-sea-ice.net/index.php?action=dlattach;topic=2591.0;attach=120497;image)
Title: Re: The 2020 melting season
Post by: Freegrass on May 09, 2020, 01:12:19 PM
41 images of Arctic mayhem cramped into a 1,94 MB video.
Title: Re: The 2020 melting season
Post by: El Cid on May 09, 2020, 04:00:25 PM
I am not an experienced meteorologist (by far), and I do not recall having seen this before, a "bridge" of high pressure/warm air cutting the Arctic so neatly into two:


Title: Re: The 2020 melting season
Post by: romett1 on May 09, 2020, 04:28:54 PM
Fram export May 04 - May 09. There is this relatively big block interesting to follow. Images: Worldview.
Title: Re: The 2020 melting season
Post by: Glen Koehler on May 09, 2020, 07:14:24 PM
So, it sure looks like someone's lying: either those who said "no meltponds there", or whomever said "after mid-April melt ponds confused the sensors".
Ditto I hope you keep participating, but Oren was correctly moderating.  Now let's get back to the weather and ice...
Title: Re: The 2020 melting season
Post by: gerontocrat on May 09, 2020, 07:47:07 PM
NSIDC monthly update for April out now. Always an interesting read.
This month a lot about the March storms and the Chukchi.

http://nsidc.org/arcticseaicenews/
Title: Re: The 2020 melting season
Post by: uniquorn on May 09, 2020, 10:24:19 PM
Welcome back Romett1. There was a second big block following but it didn't have the same resilience. Heavy contrast on this animation to highlight the many small fractures. There will probably be surface refreeze, but very little, if any, thickening from this point.
https://go.nasa.gov/3cjvdrZ, apr12-may6 with cloudiest days removed. The animation pauses to show the clearest day, apr22.
click to run, 9MB
Title: Re: The 2020 melting season
Post by: oren on May 09, 2020, 11:45:11 PM
NSIDC monthly update for April out now. Always an interesting read.
This month a lot about the March storms and the Chukchi.

http://nsidc.org/arcticseaicenews/
Thanks for this, puts things in perspective.
I was interested in the ice drift image from the end of March, at the height of the west to east transport event.
(https://forum.arctic-sea-ice.net/proxy.php?request=http%3A%2F%2Fnsidc.org%2Farcticseaicenews%2Ffiles%2F2020%2F05%2FFigure7.png&hash=1344126b28c194324865c6560d38d473)
Title: Re: The 2020 melting season
Post by: Aluminium on May 10, 2020, 07:25:53 AM
May 5-9.

2019 (https://forum.arctic-sea-ice.net/index.php/topic,2591.msg198612.html#msg198612).
Title: Re: The 2020 melting season
Post by: oren on May 10, 2020, 08:00:33 AM
Thanks Aluminium. Interesting movements all around the Arctic. The Beaufort started its typical sweeping away to the north and west, rather late this year compared to 2012, 2017, 2019 and especially 2016. The Chukchi is also moving, though quite late. The ESS, Laptev and Kara are all showing increased open water in the last couple of days, all within the envelope of past years. The Barents ice has been quite extensive, but seems vulnerable at the end of the animation, and as expected Fram export is picking up. The only region that is rather static (beyond the CAA) is Baffin, leading the race early but stalling recently.
Title: Re: The 2020 melting season
Post by: uniquorn on May 10, 2020, 02:31:34 PM
Attempting to trace the origins of romett1's big block using edge detect on ascat. It looks like it has followed a similar drift path to whoi itp116 (https://www.whoi.edu/page.do?pid=164836) Probably MYI from near the pole.
the dots are somewhat erratic, please check by another method
Title: Re: The 2020 melting season
Post by: Jim Hunt on May 10, 2020, 02:54:37 PM
Some open water is now visible in the Beaufort Sea:

https://go.nasa.gov/3bnOffs
Title: Re: The 2020 melting season
Post by: pearscot on May 10, 2020, 06:13:23 PM
I was just looking at that exact same thing on Worldview. After reviewing that region for a while, I was surprised to see how much more ice there is north of Alaska/Bering Sea. I'm not sure how much of a difference that will make...I think bottom melt is going to affect that region once it gets a bit warmer and open water exacerbates everything.

It was also posted above, but the export out of the Fram Strait has been really impressive. I also noticed a sizable chug being ripped off the most northeast coastline. Judging by the ice mobility, I still think the Greenland megacrack will reappear. As always, there is a whole lot of interesting stuff occurring
Title: Re: The 2020 melting season
Post by: Phoenix on May 10, 2020, 08:38:41 PM
Some open water is now visible in the Beaufort Sea:

https://go.nasa.gov/3bnOffs

The wind (shifting toward Alaska / Canada coast) and sub freezing temperature forecast for the Beaufort suggest that most of it might close again in a few days.

The forecast wind direction will favor open water adjacent to Banks Island.
Title: Re: The 2020 melting season
Post by: blumenkraft on May 10, 2020, 08:57:49 PM
Apropos wind.

Here is last week's ice drift map.
Title: Re: The 2020 melting season
Post by: blumenkraft on May 10, 2020, 08:58:56 PM
Fram export via SAR. Click to play.
Title: Re: The 2020 melting season
Post by: blumenkraft on May 10, 2020, 09:00:39 PM
7-day hindsight mean temperature anomalies.
Title: Re: The 2020 melting season
Post by: pearscot on May 10, 2020, 09:24:32 PM
Has transport out of the Fram been higher than normal this year or lately? That's one part of the arctic I know little about.
Title: Re: The 2020 melting season
Post by: Phoenix on May 10, 2020, 09:52:03 PM
Has transport out of the Fram been higher than normal this year or lately? That's one part of the arctic I know little about.

It has had both fast and slow phases. Wipneus has an excellent chart for that in the PIOMAS thread.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 11, 2020, 12:23:11 AM
Been busy.

Just saw the 12Z euro.

Holy mother f***ing s**t!!!

Title: Re: The 2020 melting season
Post by: Glen Koehler on May 11, 2020, 01:14:23 AM
    Climate Reanalyzer GFS
https://climatereanalyzer.org/wx/fcst/#gfs.arc-lea.t2anom (https://climatereanalyzer.org/wx/fcst/#gfs.arc-lea.t2anom)
and Earth Nullschool https://earth.nullschool.net/#2020/05/14/0600Z/wind/surface/level/orthographic=-59.54,45.21,332 (https://earth.nullschool.net/#2020/05/14/0600Z/wind/surface/level/orthographic=-59.54,45.21,332)
show
   a) Strong positive temperature anomalies for next week over most of the Arctic Ocean (ArcOc)

   b) Surface temperatures warm enough to advance ice melt over large areas of ArcOc

   c) A persistent high-pressure system over the ArcOc for the next week or more, resulting in what I interpret to be large areas of clear sky -- during mid-May with solar shortwave radiation within 6 weeks of annual max, thus beginning of the 3-month period of highest solar gain.  (The color scheme is subtle but if I remember correctly, the CR creator told me the light blue indicates clear skies over ice.)

   d) A persistent low-pressure system east of NE Greenland that creates a strong windfield on May 10-13 for increased Fram export.

     Any one of these four would be noteworthy on their own.  The combination seems remarkable.   
Title: Re: The 2020 melting season
Post by: Glen Koehler on May 11, 2020, 01:29:27 AM
... and add this to the pile
    Check out the forecast change in snow depth at https://climatereanalyzer.org/wx/fcst/#gfs.arc-lea.snowd-mslp (https://climatereanalyzer.org/wx/fcst/#gfs.arc-lea.snowd-mslp)
    I suppose that happens every May and I don't have the experience to say how the current forecast compares to the normal rate of snow depth decline, but it looks like a big drop over a 10 day period.

    It will be interesting to how this multifaceted weather assault will affect the Extent and Area stats over the coming week.  It also looks like conditions that promote melt pond development which Neven and others have pointed to as a factor that influences that the longer-term melt season.  And it makes me wonder whether the MOSAIC experiments that were left in place will still be there when the Polarstern gets back.

    PS The cumulative precip forecast supports the "clear sky under the high-pressure system" interpretation mentioned previously.
https://climatereanalyzer.org/wx/fcst/#gfs.arc-lea.aprcp (https://climatereanalyzer.org/wx/fcst/#gfs.arc-lea.aprcp)
Title: Re: The 2020 melting season
Post by: Phoenix on May 11, 2020, 02:43:32 AM
    Climate Reanalyzer GFS

   a) Strong positive temperature anomalies for next week over most of the Arctic Ocean (ArcOc)

   b) Surface temperatures warm enough to advance ice melt over large areas of ArcOc

   c) A persistent high-pressure system over the ArcOc for the next week or more, resulting in what I interpret to be large areas of clear sky -- during mid-May with solar shortwave radiation within 6 weeks of annual max, thus beginning of the 3-month period of highest solar gain.  (The color scheme is subtle but if I remember correctly, the CR creator told me the light blue indicates clear skies over ice.)

   d) A persistent low-pressure system east of NE Greenland that creates a strong windfield on May 10-13 for increased Fram export.

     Any one of these four would be noteworthy on their own.  The combination seems remarkable.   

Certainly some impressive weather conditions. But I'll share the more conservative view.

The euro forecast for >= 0C temps in the Arctic is not as ambitious as the GFS you're sharing. We'll get the facts in a few days.

The extra solar radiation due to clear skies is probably not a game changer with the Arctic Basin still covered in ice and having a high albedo.

The winds set to push ice through the Fram are truly impressive. Forecast peak  is 55 kts. We'll be in turbo mode for some days. Looks like a high intensity, short-medium duration event.

The areas where ice is most likely to remain at the minimum are the deep CAB and the regions of the Beaufort and CAA which are adjacent to the CAB. Those areas are looking better protected than at a similar point in 2019 and shouldn't be substantially impacted by this week's conditions.

So far 2020 is reminding me of the parable about the tortoise and the hare. Some definite sprinting at the moment, but also some extended periods of napping.
Title: Re: The 2020 melting season
Post by: oren on May 11, 2020, 05:51:07 AM
Snow cover in Alaska has been decimated in the past few days.
https://forum.arctic-sea-ice.net/index.php/topic,2876.msg263656.html#msg263656 (https://forum.arctic-sea-ice.net/index.php/topic,2876.msg263656.html#msg263656)
Title: Re: The 2020 melting season
Post by: Pavel on May 11, 2020, 07:47:29 AM
The Chukchi sea ice is starting to turning blue, the image of yesterday
Title: Re: The 2020 melting season
Post by: Phoenix on May 11, 2020, 07:49:17 AM
   

It just maybe that over the next week or more we will see Arctic sea ice (and snow cover) under attack on all  fronts at various times - i.e. a major warming event


How will we know if said warming event materializes and the extent of it? Something like DMI 80 ?
Title: Re: The 2020 melting season
Post by: bbr2315 on May 11, 2020, 07:52:39 AM
This impending dipole may not impact extent and area outright but it could make quite a dent on volume / export....

(https://www.tropicaltidbits.com/analysis/models/gfs/2020051100/gfs_mslpaNorm_nhem_8.png)
Title: Re: The 2020 melting season
Post by: Phoenix on May 11, 2020, 08:35:24 AM
windy.com has a nice feature that allows a user to toggle back and forth between GFS and ECMWF forecast models.

They feature is revealing a substantial difference between the models as it pertains to current warmth penetration into higher latitudes. GFS is showing >0 all the way to the north pole while ECMWF is not showing anything remotely close to that.

Please remember to incorporate an appreciation for a level of uncertainty in the forecasts being presented, particularly when there is strong model disagreement. Those Climate Reanalyzer images are based upon the projections of the GFS model. They are not facts.

Title: Re: The 2020 melting season
Post by: grixm on May 11, 2020, 11:04:32 AM
windy.com has a nice feature that allows a user to toggle back and forth between GFS and ECMWF forecast models.

They feature is revealing a substantial difference between the models as it pertains to current warmth penetration into higher latitudes. GFS is showing >0 all the way to the north pole while ECMWF is not showing anything remotely close to that.

Please remember to incorporate an appreciation for a level of uncertainty in the forecasts being presented, particularly when there is strong model disagreement. Those Climate Reanalyzer images are based upon the projections of the GFS model. They are not facts.

I suspect this is mostly due to differences in how the models simulate the air very close to the ground, where temperatures will be mostly capped to max near 0 degrees due to interactions with the ice. The 850 hPa temperature anomaly is a pretty good indication of where the ground temperature anomaly wants to be had it not been for the ice, and if you look at that, the GFS and Euro are very similar in intensity. In fact at some frames the Euro looks even warmer over the pole than the GFS does. Below is the GFS and Euro respectively at +48h.



Title: Re: The 2020 melting season
Post by: Phoenix on May 11, 2020, 11:33:36 AM

The 850 hPa temperature anomaly is a pretty good indication of where the ground temperature anomaly wants to be had it not been for the ice, and if you look at that, the GFS and Euro are very similar in intensity. In fact at some frames the Euro looks even warmer over the pole than the GFS does. Below is the GFS and Euro respectively at +48h.

The 850 hPa temperature is somewhere away from the ice. I'm not sure of the altitude, maybe someone with more knowledge than me can provide that.

But it is the temperature adjacent to the ice that is going to impact the ice, not the temperature 1,000 feet above sea level. For the benefit of the lurkers who are reading the thread, I think it's useful to kick the tires and questions some assumptions about the magnitude of the current events.

The heat coming into the Chukchi and ESS and the high winds pushing ice through Fram is quite significant and easily understandable and acceptable. No problem.

Maintaining heat over ice for a very long distance over ice and delivering it to the surface of much of the CAB where it can impact the ice in May is a completely differently animal. Skepticism of this is healthy from a scientific perspective.

 
Title: Re: The 2020 melting season
Post by: gerontocrat on May 11, 2020, 11:33:52 AM
   

It just maybe that over the next week or more we will see Arctic sea ice (and snow cover) under attack on all  fronts at various times - i.e. a major warming event


How will we know if said warming event materializes and the extent of it? Something like DMI 80 ?
Being mid-May, a significant & sustained warming event should show up in extent, area & volume losses greater than average. and in accelerated snow cover extent & snow water equivalent reductions.

Temps North of 80 from DMI is just one of those measures, but this event looks like causing happenings at various times at all points North of 50 as weather systems traverse the Arctic & beyond..

It is 1030 am. & still no JAXA data - patience is a virtue?
Title: Re: The 2020 melting season
Post by: BornFromTheVoid on May 11, 2020, 11:53:30 AM
The 850 hPa temperature is somewhere away from the ice. I'm not sure of the altitude, maybe someone with more knowledge than me can provide that.

But it is the temperature adjacent to the ice that is going to impact the ice, not the temperature 1,000 feet above sea level. For the benefit of the lurkers who are reading the thread, I think it's useful to kick the tires and questions some assumptions about the magnitude of the current events.

The heat coming into the Chukchi and ESS and the high winds pushing ice through Fram is quite significant and easily understandable and acceptable. No problem.

Maintaining heat over ice for a very long distance over ice and delivering it to the surface of much of the CAB where it can impact the ice in May is a completely differently animal. Skepticism of this is healthy from a scientific perspective.

Surface air temperatures over the ice are held close to a 0C maximum due to the latent heat of fusion of ice. This is quite apparent each year on the DMI 80N temperatures. For that reason, using something like the 850hPa temperature (or the less common, 925hPa value) is useful for assessing the relative heat mass over the ice. It's far from perfect, and temperature inversions, fog and such will add more complications, but much of the time in summer, 850hPa temperatures are more useful than surface temperatures.
Title: Re: The 2020 melting season
Post by: Aluminium on May 11, 2020, 11:58:36 AM
High air affects ice via infrared radiation from thick layer. This power is comparable with sunlight.
Title: Re: The 2020 melting season
Post by: be cause on May 11, 2020, 12:06:05 PM
... and after gfs's improvements last year they are no longer an outlier ( or out'n'out liar :) ) with regard to forecast heat in the Arctic basin .

.. and last year Neven was saying anticyclonic weather in May was no bad thing when it came to ice survival . Good to have another chance to observe .. b.c.
 
Title: Re: The 2020 melting season
Post by: Niall Dollard on May 11, 2020, 12:32:55 PM
For temperatures at 2 metres, I have not found the GFS to be particularly accurate across the Arctic basin. These are modelled temperatures and it tends sometimes to err on the positive side. (sometimes too it can go the other way).

Real data is sparse. We do have the Polarstern reporting currently at 83.5 N 13.1 E

Its temperature at 9UTC today was -13.4 C. Using Nullschool, the GFS model is showing a temperature of -9.3 C for same time/location. 

850hPa temps are useful to help show the expected air mass moving in. But it should always be remembered that these are temps at circa 1500 metres, way above the ice.

The Arctic is well known for temperature inversions (as mentioned already by BFTV). Fog/mist and stratus can often form over the surface of the ice keeping temps there cool when the sun is shining only a short distance higher up.



I think this low pressure in the Fram Strait on Wednesday will be very significant for ice export. NE coast of Greenland is expected to be battered by north winds gusting to 120 km/hr, extending well down the Fram.   
Title: Re: The 2020 melting season
Post by: bluice on May 11, 2020, 12:46:29 PM
.. and last year Neven was saying anticyclonic weather in May was no bad thing when it came to ice survival . Good to have another chance to observe .. b.c.
 
2019 season thread has plenty of discussion about that.

But if my memory serves me right, the conclusion was that sunshine per se is not necessarily that bad for ice in the early season. Albedo is high and surface temperature stays low. This time, however, we are getting a "hot high" with warm air mass that could initiate surface melt thus lowering albedo.
Title: Re: The 2020 melting season
Post by: Phoenix on May 11, 2020, 01:08:18 PM

Surface air temperatures over the ice are held close to a 0C maximum due to the latent heat of fusion of ice. This is quite apparent each year on the DMI 80N temperatures. For that reason, using something like the 850hPa temperature (or the less common, 925hPa value) is useful for assessing the relative heat mass over the ice. It's far from perfect, and temperature inversions, fog and such will add more complications, but much of the time in summer, 850hPa temperatures are more useful that surface temperatures.

Temperatures over the ice surface are not held close to zero everywhere. They are well above zero over the ice near the coast in the ESS and Chukchi at the moment. Seems the latent heat of fusion doesn't work when the ice is near a giant heated rock (Siberia) ??

Surface temps N of 80N stay close to zero because they are far away from the big heated rocks of Siberia and NA. That's why the ice remains there at the September minimum. Transporting enough heat over long distance to the surface of the CAB ice is not a trivial matter.



Title: Re: The 2020 melting season
Post by: grixm on May 11, 2020, 01:23:21 PM
Surface temps N of 80N stay close to zero because they are far away from the big heated rocks of Siberia and NA. That's why the ice remains there at the September minimum. Transporting enough heat over long distance to the surface of the CAB ice is not a trivial matter.

Transporting air from the south is not the only way the pole can warm up. High pressure areas, like the one being forecast now, causes sinking air, and air warms as it sinks. Which also increases the relevance of the 850 hPA air temperature, because that air is moving downwards toward the surface.
Title: Re: The 2020 melting season
Post by: Phoenix on May 11, 2020, 01:28:40 PM

Real data is sparse. We do have the Polarstern reporting currently at 83.5 N 13.1 E

Its temperature at 9UTC today was -13.4 C. Using Nullschool, the GFS model is showing a temperature of -9.3 C for same time/location. 

850hPa temps are useful to help show the expected air mass moving in. But it should always be remembered that these are temps at circa 1500 metres, way above the ice.


Marvelous !! Actual surface data showing a 4C discrepancy from the GFS model (which runs hot in this instance).

I found similar discrepancies between the GFS and ECMWF (also a model) on Windy.com. You provide a single corroborating data point regarding the better accuracy of the euro model.

Thank you Niall.
Title: Re: The 2020 melting season
Post by: Carex on May 11, 2020, 01:32:55 PM
Meanwhile, in sub-arctic melt progress, as of yesterday, the Great Lakes are now ice free, despite four consecutive mornings of fresh snow.  Black and Nipigon Bays, Lake Superior gave up the ghost to strong winds while temperatures hovered between -5 and +2.
Title: Re: The 2020 melting season
Post by: Jim Hunt on May 11, 2020, 01:36:47 PM
Something like DMI 80 ?

Nope. That's heavily weighted towards the Pole.

What's more at this time of year < 80N is far more relevant than >80N
Title: Re: The 2020 melting season
Post by: binntho on May 11, 2020, 01:38:05 PM
Surface temps N of 80N stay close to zero because they are far away from the big heated rocks of Siberia and NA. That's why the ice remains there at the September minimum. Transporting enough heat over long distance to the surface of the CAB ice is not a trivial matter.

Always interesting to read new theories of physics and meteorology in this forum.

I wonder why people think that the landmasses of Alaska and Sibera are more significant sources of heat in summer, than are the open ocean areas surrounding the ice. The open ocean absorbs much more solar energy than does dry land, has a much higher heat capacity, and has the ability to move the heat to the ice directly rather than going through the ethereal media of air.

Without the landmasses surrounding the Arcitic Ocean, I'd guess that the ice would disappear every summer. If there was no Antarctic Continent and just open ocean on the South Pole, it would lose all it''s ice every summer (methinks). It's the presence of the vast Antartic landmass that maintains the antarctic sea ice, and the same can be said for the Arctic Ocean, the ice survives by sheltering behind the landmass of America in particular, Siberia to a lesser extent.
Title: Re: The 2020 melting season
Post by: Niall Dollard on May 11, 2020, 01:53:08 PM
Yes Binntho. I suspect as more ice in the periphery goes each summer, it will be bottom melt that will take a signficant toll on the ice >85N.

Title: Re: The 2020 melting season
Post by: Phoenix on May 11, 2020, 02:05:35 PM

Transporting air from the south is not the only way the pole can warm up. High pressure areas, like the one being forecast now, causes sinking air, and air warms as it sinks. Which also increases the relevance of the 850 hPA air temperature, because that air is moving downwards toward the surface.

Not saying that air transport is the ONLY way to get heat to the pole. The ocean will ultimately do the trick if we don't deal with AGW.

But air transport is a seriously important weapon in the current arsenal and distance from hot land is a critical defense mechanism for the CAB. I am a proponent of the possibility that the inner Arctic is much more resilient than most people think.

Bottom line is that there have been quite a few GFS model based charts being shared here the last
few days and a less educated reader might be misled by them. They should not be interpreted as a reliable indicator of surface heat in the CAB.
Title: Re: The 2020 melting season
Post by: Freegrass on May 11, 2020, 02:18:54 PM
Five Day Forecast
Wind + Temp @ 1000hPa

Is the 1000hPa as useful as the 850hPa?
Title: Re: The 2020 melting season
Post by: Phoenix on May 11, 2020, 02:27:06 PM

I wonder why people think that the landmasses of Alaska and Sibera are more significant sources of heat in summer, than are the open ocean areas surrounding the ice. The open ocean absorbs much more solar energy than does dry land, has a much higher heat capacity, and has the ability to move the heat to the ice directly rather than going through the ethereal media of air.


You're arguing a completely different point. Yes, the ocean has a higher heat capacity than the land. That's why the ocean retains it's heat and the land contributes heat to the atmosphere where it can slide over and melt the ice at the surface.

The issue in the ocean is completely different. There is a shit ton of heat below the Arctic that can melt it many times over.  The obstacle is a fresh water lens at the top which is less dense than warm salty water below.

Please explain the physics of the ocean overcoming the density gradient.

Title: Re: The 2020 melting season
Post by: bluice on May 11, 2020, 03:14:58 PM
Phoenix, I don't have the knowledge to answer your questions but I think there are more appropriate threads for them than the main one

Maybe you can take a look at one of these for example:
https://forum.arctic-sea-ice.net/index.php/topic,143.0.html
https://forum.arctic-sea-ice.net/index.php/topic,2417.0.html
https://forum.arctic-sea-ice.net/index.php/topic,2709.0.html
Title: Re: The 2020 melting season
Post by: oren on May 11, 2020, 06:05:01 PM
Thank you bluice.
All, please remember this thread is not to be bogged down in back and forth arguments, so once something becomes a thing take it elsewhere. And please be aware that someone will always disagree, no need to get defensive or personally respond to every point. The melting season knows better than us all and often patience is the best tool in the ice enthusiast arsenal. If you're right, you'll be proven right. If you're wrong, you'll be proven wrong. And if it depends on weather and luck, best not to make big predictions. Let the thread breathe, wait for new data to come in, I promise it will be interesting.
Title: Re: The 2020 melting season
Post by: igs on May 11, 2020, 07:41:59 PM
It is 1030 am. & still no JAXA data - patience is a virtue?



Patience has paid of:


https://ads.nipr.ac.jp/vishop/#/extent (https://ads.nipr.ac.jp/vishop/#/extent)


If that's what you meant
Title: Re: The 2020 melting season
Post by: oren on May 11, 2020, 09:41:24 PM
The ADS website is back up, but the extent data is still only up to May 7th.
Title: Re: The 2020 melting season
Post by: thejazzmarauder on May 12, 2020, 01:26:25 AM
.. and last year Neven was saying anticyclonic weather in May was no bad thing when it came to ice survival . Good to have another chance to observe .. b.c.
 
2019 season thread has plenty of discussion about that.

But if my memory serves me right, the conclusion was that sunshine per se is not necessarily that bad for ice in the early season. Albedo is high and surface temperature stays low. This time, however, we are getting a "hot high" with warm air mass that could initiate surface melt thus lowering albedo.
May 2016 might end up being a good analog; check out the temperature and hPa anomalies over the arctic.
Title: Re: The 2020 melting season
Post by: Phoenix on May 12, 2020, 02:51:13 AM
First sighting of a positive SST in the Beaufort Sea. +1C temperatures in a small region off the Canadian coast, just E of Alaska.

https://www.windy.com/-Sea-temperature-sst?sst,2020-05-21-06,69.119,-137.706,6,m:fATaclQ
Title: Re: The 2020 melting season
Post by: Phoenix on May 12, 2020, 03:24:05 AM
Fairbanks hit 82F (28C) yesterday, record for the date is 84F.

https://www.inquirer.com/weather/philadelphia-weather-record-fairbanks-alaska-polar-vortex-20200510.html

Central Alaska is the primary heat source for the melting event taking place in the Chukchi and ESS. Facilitated by the Arctic high and Bering / Siberia low which is pulling the air from AK toward Siberia.
Title: Re: The 2020 melting season
Post by: bbr2315 on May 12, 2020, 03:26:31 AM
I have a feeling the GFS is overdoing the rapid snow-melt in some regions, as is its typical bias (I think its initialized depth levels are generally too low). This explains the discrepancy between GFS / CMC + EURO. While we are certainly in for a dipole, and it may be unprecedented in both scope and warmth, I do think the GFS may be overdone. The CMC has an excellent handle on Canadian snowcover, from my experience, while EURO is probably best hemispherically.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 12, 2020, 05:11:54 AM
I don't mean to be rude but who cares about modeled 2M y
Temps.

Let's take a look at only thing that really matters.

Surface albedo. So for May 11th everything looks as you would expect.

The surface albedo is steadily dropping quickly over the ESS and Chuckchi and that line is marching North.

The thing that stands out to me is how sunny things are.

Man it won't take long under sunny conditions with the current solar insolation levels equal to July 30th for surface albedo to plummet.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 12, 2020, 05:27:28 AM
Just took a look at the 12Z euro.

The huge ridging slowly sliding across the arctic the next 10 days is stunning.


It's going to be 24 hours a day sun.

Granted that's not the same sun as in June.

But there is no way with that kind of wall to wall solar beating the surface albedo won't decay over a large portion of the Arctic basin.

In the biggest melt years like 07, 10, 11, 12, 15, and 16 we didn't see arctic basin albedo really drop until the second week of June or later.

In 2012 IIRC it really plummeted at the end of the first week of June and that was still really early.

Maybe it's not physically plausible yet with the solar elevation angle and what not.

But insolation today between 70-90N is already above 417W/m2 by the 22nd that's about 475w/m2.



This could be the breakthrough. 



Look this is simple.... If by the 20th a large portion of the Arctic basin has seen surface albedo drop from the largely pristine 0.85 dry snow to 0.60 wet snow and 0.5-0.6 bare/wet ice with 10 days left in May.

Like HOLY SHIT!
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 12, 2020, 05:38:53 AM
For May 12th at 75N

You get about 10 hours with the sun above 20° altitude.

The solar altitude peak is 34°

You get about 6 hours at 30°+.

At 81N you got about 10 hours above 20° and 6 hours above 25° peaking at 30°

Obviously everyday that passes the solar altitude increases quickly

Title: Re: The 2020 melting season
Post by: oren on May 12, 2020, 05:39:30 AM
Temps in Pevek (ESS) have been running at record or near-record high for the date in the last 4 days.
Title: Re: The 2020 melting season
Post by: pearscot on May 12, 2020, 05:58:43 AM
The impact of the sun will be very interesting to follow. I was also extremely surprised to see how warm it was in central Alaska. I've been reading the detailed forecast discussion for Barrow to get a better handle on what to expect in that small corner of the arctic. In sum, the aforementioned snow melt is noted with several rivers at elevated flow rates.

Beyond that, I've been surprised with basic visual comparisons of sea ice coverage throughout the entire arctic. The most notable difference, to my eye, is the extent this year into the Bering Sea/north of Alaska. There are also some areas around Greenland which certainly have more robust sea ice in far better condition compared to the same date last year. I'm not sure how much of a difference all of that will make going forward.

One still can't deny the data and realize that while some areas have more ice this year, others have less. The most interesting component of the distribution of ice will be to see how quickly it melts out and if it looks like subsurface melting will be intensified by both Atlantification (and I'm not even sure if Pacification is a term, but that too). So much to focus on right now, but I have a much better handle on the state of the ice now than I did in January.
Title: Re: The 2020 melting season
Post by: charles_oil on May 12, 2020, 06:00:27 AM

Oren - any chance of some titles for the Pevek graph ?  Not sure what we are seeing …. different sensors / years / averages ?  Tks
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 12, 2020, 06:30:39 AM
The Kara.  Atleast half of it gets a big time blast of warmth over the next 72 hours.


That will decimate surface albedo there.

The 00z gfs through 192 hours is absurd.

The laptev bite will dramatically open up.

Title: Re: The 2020 melting season
Post by: aperson on May 12, 2020, 07:11:05 AM
I agree with friv, and think one additional ingredient here is the amount of ice that will be sent down the death zone past Svalbard and out the Fram strait. We're looking at 4+ days of strong surface winds exporting ice. Just look at how packed the isobars are on this output and how well they are positioned to export ice.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 12, 2020, 07:58:41 AM
I agree with friv, and think one additional ingredient here is the amount of ice that will be sent down the death zone past Svalbard and out the Fram strait. We're looking at 4+ days of strong surface winds exporting ice. Just look at how packed the isobars are on this output and how well they are positioned to export ice.

That ain't no joke that is crazy you're going to see open water come in the kara or the laptev because of all this
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 12, 2020, 08:04:04 AM
I agree with friv, and think one additional ingredient here is the amount of ice that will be sent down the death zone past Svalbard and out the Fram strait. We're looking at 4+ days of strong surface winds exporting ice. Just look at how packed the isobars are on this output and how well they are positioned to export ice.

That ain't no joke that is crazy you're going to see open water come in the kara or the laptev because of all this

The Kara gets blasted with straight heat.

However far that warn sector reaches into the Arctic ice albedo is toast.

Title: Re: The 2020 melting season
Post by: Lord M Vader on May 12, 2020, 08:38:43 AM
Kara should implode soon.

Another area that should see damage is the area just north of Svalbard. Hammered by a 961 hpa bomb cyclone in tandem with a 1044 hpa high pressure over the CAB will push some thick ice piled up there out in the Atlantic killer zone. However, this won't last long but should nevertheless have an impact on the ice.

Later in the forecast period, Laptev will take a big hit.
Title: Re: The 2020 melting season
Post by: thejazzmarauder on May 12, 2020, 09:08:06 AM
A year ago to the day, there was forecasted high pressure that resulted in some interesting analysis. Take a look at the 2019 melting season thread from 5/12/19 through about 5/21/19: https://forum.arctic-sea-ice.net/index.php/topic,2591.800.html
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 12, 2020, 09:46:07 AM
A year ago to the day, there was forecasted high pressure that resulted in some interesting analysis. Take a look at the 2019 melting season thread from 5/12/19 through about 5/21/19: https://forum.arctic-sea-ice.net/index.php/topic,2591.800.html

We had a short lived dipole that helped open water and keep 2019 second lowest extent.

This is different and unprecedented in the modern era.  I'm sure you might find this somewhere in the historical record from Noaa back 200 years.

But this is a potential near basin wide albedo buster.

Look this this ridge.  It's amazing.

And the partial sat image shows the carved out sunny circle.

Similar to June 2007.

We can see the ice albedo is already compromised over the ESS and laptev.

The lighter color in the Arctic basin the last 2 days has started to darken.  Once it turns red the cooling properties of a surface reflecting .85 insolation is gone and a drop to .5-.6 is a HUGE difference


Title: Re: The 2020 melting season
Post by: Aluminium on May 12, 2020, 09:55:26 AM
May 7-11.

2019 (https://forum.arctic-sea-ice.net/index.php/topic,2591.msg198910.html#msg198910).
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 12, 2020, 09:58:55 AM
This is a very non scientific animation of 07,10,11,12,15,16,18,19, and 2020 for May 14th including the GFS forecast for May 14th.

Look, one image is not like the others.

Is amazing, this might be the big breakthrough to see the ice truly decimated if this 🌞 bathe can get the wide basin surface to start melting by the 20th it would be weeks ahead of 2012.

WEEKS!!


I guess you have to click to animate.

How do I just get it to animate?

(https://i.ibb.co/qsVm4Jt/158927000814233059.gif) (https://ibb.co/d2xk3md)


(https://i.ibb.co/qsVm4Jt/158927000814233059.gif) (https://ibb.co/d2xk3md)
Title: Re: The 2020 melting season
Post by: Aluminium on May 12, 2020, 10:23:34 AM
Wrangel Island reached positive dew point.
Title: Re: The 2020 melting season
Post by: oren on May 12, 2020, 10:23:51 AM
Thank you for the animation and the analysis Friv. It loads automatically if it is narrow enough, I think <700 pixels, but it's actually much better when it requires a click because some members data link is limited or expensive.
Title: Re: The 2020 melting season
Post by: oren on May 12, 2020, 10:31:53 AM
Here is another Wrangel temp chart.
To Charles_oil's question, the graph shows the month of May so far, with daily high, low and average, and the climate long-term high low and average. Dots are the highest high and lowest low for the date. When the chart touches the dot, it means record high was set this year.
It comes from a very useful Russian-language site, which also has charts of any past month of your choosing.
http://www.pogodaiklimat.ru/monitor.php?id=21982 (http://www.pogodaiklimat.ru/monitor.php?id=21982)
Title: Re: The 2020 melting season
Post by: SteveMDFP on May 12, 2020, 10:42:54 AM
There are also some areas around Greenland which certainly have more robust sea ice in far better condition compared to the same date last year. I'm not sure how much of a difference all of that will make going forward.

Most of the ice on the east side of Greenland has been exported from the CAB through the Fram Strait.  It's a contrary indicator for the health of the Arctic ice.  It will keep moving south and be melted in short order.  The ASCAT radar image animations that get periodically posted show this nicely.
Title: Re: The 2020 melting season
Post by: Phoenix on May 12, 2020, 10:57:16 AM
JAXA #'s are up again. 2020 is ~450K km2 behind 2016 in terms of extent. A good week behind the pacesetter.



Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 12, 2020, 11:16:37 AM
Here is another Wrangel temp chart.
To Charles_oil's question, the graph shows the month of May so far, with daily high, low and average, and the climate long-term high low and average. Dots are the highest high and lowest low for the date. When the chart touches the dot, it means record high was set this year.
It comes from a very useful Russian-language site, which also has charts of any past month of your choosing.
http://www.pogodaiklimat.ru/monitor.php?id=21982 (http://www.pogodaiklimat.ru/monitor.php?id=21982)

That's not surprising.

I believe it has already been posted

But Pevek, Russia on the ESS shore is straight unprecedented blow torching.

Two record highs.  4-5 days in a row with high temps breaking or running at record highs.

The daily means are now running above 0C.  Just incredible.

The past two days the minimum has been about 5C???? 

What the fuck??? Is this weather station really on the ESS coast?

It's May 12th!!!!

The high temps the last two days have been under 1C from a record while the 8th and 9th were records.

I'm blown away. 

The preconditioning taking place is hard to believe

Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 12, 2020, 11:26:10 AM
My last post for today.

I close up screenshots of the terra-367 day image of Pevek from like 4-5 days ago.

You can see the huge regional change when the surface was relatively dry and became wet.

The 3rd image is today. A few hours ago. Very red = very wet= albedo drop.

ITS MAY 12TH
Title: Re: The 2020 melting season
Post by: Aluminium on May 12, 2020, 11:43:10 AM
Is this weather station really on the ESS coast?
Yes. It's foehn.
Title: Re: The 2020 melting season
Post by: Niall Dollard on May 12, 2020, 12:14:07 PM
Is this weather station really on the ESS coast?
Yes. It's foehn.

Pevek is sheltered somewhat (especially from an east or southeast direction) located on an inlet.

It does have some form when it comes to reporting high temperatures. It happens only rarely but it has reached 17.1 C in May and even 8.9 C in January.
Title: Re: The 2020 melting season
Post by: Paul on May 12, 2020, 01:14:18 PM
Some quite astonishing weather occuring for May that is ff
or sure, even though upper air temperatures are not really remarkable(compare to what we usually get in summer) the impacts in the ESS is impressive and alarming. Not sure much melt is happening but you can just see what a bit of wind is doing to the ice and there is already alot of dark open water appearing. Only 2017 had anything similar and the CAB managed to hang on in there but either way, the ice in the ESS is in trouble and we could see a record retreat here.

The storm that is about to hit Svalbard is very impressive although thankfully shortlived, I guess one crumb of comfort, its better for the ice to hit at the edge of the basin than right over the pole.
Title: Re: The 2020 melting season
Post by: blumenkraft on May 12, 2020, 01:18:11 PM
... Not sure much melt is happening ...

Surface melt observed here:

https://forum.arctic-sea-ice.net/index.php/topic,2649.msg263808.html#msg263808
Title: Re: The 2020 melting season
Post by: paolo on May 12, 2020, 01:19:41 PM
I take the liberty of adding this Worldview image from Pevek
Title: Re: The 2020 melting season
Post by: uniquorn on May 12, 2020, 01:27:30 PM
Following up on Friv's terra modis post above.
https://go.nasa.gov/2zAOiar, apr24-12, click to run
Quote
Corrected Reflectance (Bands 3-6-7)
Temporal coverage: 24 February 2000 - Present

False Color: Red = Band 3, Green = Band 6, Blue = Band 7

This combination is used to map snow and ice. Snow and ice are very reflective in the visible part of the spectrum (Band 3), and very absorbent in Bands 6 and 7 (short-wave infrared, or SWIR). This band combination is good for distinguishing liquid water from frozen water, for example, clouds over snow, ice cloud versus water cloud; or floods from dense vegetation. This band combination is only available for MODIS (Terra) because 70% of the band 6 sensors on the MODIS instrument on the Aqua satellite failed shortly after launch.

The MODIS Corrected Reflectance imagery is available only as near real-time imagery. The imagery can be visualized in Worldview and the Global Imagery Browse Services (GIBS. The sensor resolution is 500 m and 250 m (Bands 1 and 2 have a sensor resolution of 250 m, Bands 3 – 7 have a sensor resolution of 500 m, and Bands 8 - 36 are 1 km. Band 1 is used to sharpen Band 3, 4, 6, and 7), imagery resolution is 250 m, and the temporal resolution is daily.

Snow and Ice
Since the only visible light used in these images (Band 3) is assigned to red, snow and ice appear bright red. The more ice, the stronger the absorption in the SWIR bands, and the more red the color. Thick ice and snow appear vivid red (or red-orange), while small ice crystals in high-level clouds will appear reddish-orange or peach.

Vegetation
Vegetation will appear green in this band combination, as vegetation is absorbent in Bands 3 and 7, but reflective in Band 6. Bare soil and deserts will appear bright cyan in the image since it much more reflective in Band 6 and 7 than Band 3.

Water
Liquid water on the ground will appear very dark since it absorbs in the red and the SWIR, but small liquid water drops in clouds scatter light equally in both the visible and the SWIR, and will therefore appear white. Sediments in water appear dark red.
MODIS Corrected Reflectance vs. MODIS Surface Reflectance

The MODIS Corrected Reflectance algorithm utilizes MODIS Level 1B data (the calibrated, geolocated radiances). It is not a standard, science quality product. The purpose of this algorithm is to provide natural-looking images by removing gross atmospheric effects, such as Rayleigh scattering, from MODIS visible bands 1-7. The algorithm was developed by the original MODIS Rapid Response team to address the needs of the fire monitoring community who want to see smoke. Corrected Reflectance shows smoke more clearly than the standard Surface Reflectance product. In contrast, the MODIS Land Surface Reflectance product (MOD09) is a more complete atmospheric correction algorithm that includes aerosol correction, and is designed to derive land surface properties. In clear atmospheric conditions the Corrected Reflectance product is very similar to the MOD09 product, but they depart from each other in presence of aerosols. If you wish to perform a complete atmospheric correction, please do not use the Corrected Reflectance algorithm. An additional difference is that the Land Surface Reflectance product is only tuned for calculating the reflectance over land surfaces.
Interpretation of redness is the key here.
Heavy contrast of Terra(True colour), may12 in an attempt to show if there is a difference in albedo over the affected area. cffr
uni-hamburg amsr2-uhh, bering-chukchi-ess, may4-11 for overview, ctr
Title: Re: The 2020 melting season
Post by: Freegrass on May 12, 2020, 01:31:02 PM
...the ice in the ESS is in trouble and we could see a record retreat here.
Isn't ice going to pile up in the ESS because of that huge anticyclone?
Or will the ice move away from the coast because of those anticyclonic winds that compact the ice pack?
Title: Re: The 2020 melting season
Post by: Freegrass on May 12, 2020, 01:59:12 PM
We don't talk much about Bering Strait export, but it looks like this week we'll see lots of it. The Bering sea will have a significant drop in extent I presume...
Title: Re: The 2020 melting season
Post by: gandul on May 12, 2020, 02:04:29 PM
Big change in Alaska snow cover.

Siberia shows it has been under an anomalously warm blob for year to date
Title: Re: The 2020 melting season
Post by: Paul on May 12, 2020, 04:49:46 PM
...the ice in the ESS is in trouble and we could see a record retreat here.
Isn't ice going to pile up in the ESS because of that huge anticyclone?
Or will the ice move away from the coast because of those anticyclonic winds that compact the ice pack?

As it stands the winds are pushing the ice away from the Siberian landmass and partly away from the little fast ice we actually do have this year. Any subtle changes in wind direction may close those holes up again somewhat(just have to see where this high ends up) but the ice looks largely thin in the ESS this year with only some slightly larger blocks.

Reckon the ESS is going to be shocking early melt season story after last years early Beaufort sea retreat.
Title: Re: The 2020 melting season
Post by: blumenkraft on May 12, 2020, 06:10:40 PM
Comparison of 2019 vs. 2020
Title: Re: The 2020 melting season
Post by: Freegrass on May 12, 2020, 08:15:57 PM
...the ice in the ESS is in trouble and we could see a record retreat here.
Isn't ice going to pile up in the ESS because of that huge anticyclone?
Or will the ice move away from the coast because of those anticyclonic winds that compact the ice pack?

As it stands the winds are pushing the ice away from the Siberian landmass and partly away from the little fast ice we actually do have this year. Any subtle changes in wind direction may close those holes up again somewhat(just have to see where this high ends up) but the ice looks largely thin in the ESS this year with only some slightly larger blocks.

Reckon the ESS is going to be shocking early melt season story after last years early Beaufort sea retreat.
I agree that the ESS is in terrible shape this year. And - correct me if I'm wrong - the cause of this is the counterclockwise motion of the ice pack this winter. So I'm very curious to see if by the end of the week a change in that rotation will have filled the ESS back up again.

Edit: Uniquorn just posted a video of this years freezing season, and it clearly shows the counterclockwise movement I was talking about. Most of it happened last month when we had that huge export out of the Fram. This pulled a lot of ice out of the ESS as well, that I think could be (partially?) filled up again this week.

https://forum.arctic-sea-ice.net/index.php/topic,2417.msg263883.html#msg263883
Title: Re: The 2020 melting season
Post by: uniquorn on May 12, 2020, 09:37:28 PM
Edit: Uniquorn just posted a video of this years freezing season, and it clearly shows the counterclockwise movement I was talking about.
https://forum.arctic-sea-ice.net/index.php/topic,2417.msg263883.html#msg263883
You may be confusing ice rotation with a swath rotation artifact on ASCAT which is enhanced by that interferometry method. Beaufort and Western CAA/CAB don't show significant anti-clockwise motion up to now.
Title: Re: The 2020 melting season
Post by: Freegrass on May 12, 2020, 09:44:22 PM
Beaufort and Western CAA/CAB don't show significant anti-clockwise motion up to now.
True. It only happened for a short period of time, when we had that big Fram export event. But it was significant enough to clear the ESS from a lot of ice.
Title: Re: The 2020 melting season
Post by: uniquorn on May 12, 2020, 10:05:12 PM
wipneus regional extent and area, ESS, may11
Title: Re: The 2020 melting season
Post by: Freegrass on May 12, 2020, 10:14:45 PM
ESS today on worldview.
Title: Re: The 2020 melting season
Post by: uniquorn on May 12, 2020, 10:39:01 PM
Edit: Uniquorn just posted a video of this years freezing season, and it clearly shows the counterclockwise movement I was talking about.
https://forum.arctic-sea-ice.net/index.php/topic,2417.msg263883.html#msg263883
Well let's just leave it that I don't agree with your interpretation of that animation. :)
Title: Re: The 2020 melting season
Post by: Freegrass on May 12, 2020, 10:50:29 PM
Edit: Uniquorn just posted a video of this years freezing season, and it clearly shows the counterclockwise movement I was talking about.
https://forum.arctic-sea-ice.net/index.php/topic,2417.msg263883.html#msg263883 (https://forum.arctic-sea-ice.net/index.php/topic,2417.msg263883.html#msg263883)
Well let's just leave it that I don't agree with your interpretation of that animation. :)
What is it they say about democracy? That it's an organized disagreement?  ;)
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 13, 2020, 02:57:34 AM
Like what the??

Where is the canopy of clouds??

Almost the entire Arctic basin is sunny.

On May 12th that's unheard of
Title: Re: The 2020 melting season
Post by: Paul on May 13, 2020, 03:58:43 AM
Well a large part of the basin is sunny but near the pole and at times the Beaufort sea its cloudier, I don't think that is unusual in itself especially with high pressure in charge.

Obviously what is unusual is just how high the pressure is in this high(around 1045MB) and the 'warm' air for the time of year that is inside it, if albeit the cavet the GFS 2M temps may be overdoing it somewhat basing on other discussions on here.

Indications from the model this high will transfer towards the ESS/Laptev and may finally weaken and a fairly slack set up may occur. The coldest conditions likely to be in the Beaufort sea and ice drifting along the Beaufort Gyre may slow down also and it may start covering any open water there. Either way, I'll be very surprised if we see a repeat of last year in the Beaufort and it will be all eyes on the ESS.

I also think it's too simple saying high pressure is bad for the ice and low pressure is good for the ice, I think the issue with this high for me is that the air has warmed up to above average levels for the time of year and its at lower latitudes of the basin so sunshine damage may play more a part than if the high was over the pole itself.
Title: Re: The 2020 melting season
Post by: ReverendMilkbone on May 13, 2020, 04:17:47 AM
From Climate reanalyzer, 10 day NH temp anomaly...wow.
Title: Re: The 2020 melting season
Post by: Phoenix on May 13, 2020, 04:46:08 AM
Over in the data thread, Gerontocrat is emphasizing the positive Arctic temperature anomaly.

For the benefit of lurkers and newcomers, I would like to emphasize that the Arctic is still largely a wilderness and we are short on real temperature data. There is considerable disagreement between the GFS and Euro models about the temperature data with the GFS running notably warmer in general.

Niall recently posted an actual data point from the research vessel Polarstern demonstrating that the actual temperature in a single location was 4C lower than what the GFS model was spitting out for the same time and location.

In the case of temperatures, the data thread is not sharing observed results. Nor is it a model consensus. It's just one version of a story with multiple perspectives.

My hunch is that the lower temperatures from the euro model are more accurate, but I acknowledge that I have a bias that I want that data to be more accurate. I don't want to see the imminent demise of the ice and I'm interested in the possibility that something something approaching a BOE is still avoidable.

Title: Re: The 2020 melting season
Post by: pearscot on May 13, 2020, 04:57:18 AM
Holy shit this year is off to a wild start. I was actually amazed when I compared the Bering Strait this year with 2012...they look almost identical on this day. The Arctic just keeps surprising.

I can't wait for the clouds to clear above northern Greenland so I can take a look at its north shore. I did a VERY rough measurement with the Worldview distance tool, and the large iceberg traversing the Fram has gone roughly ~280km south (since leaving the main pack).
Title: Re: The 2020 melting season
Post by: Phoenix on May 13, 2020, 05:11:09 AM
From Climate reanalyzer, 10 day NH temp anomaly...wow.

Again, for the benefit of those learning....

The GFS image being presented here is comparing forecasted temperatures from the GFS model to the average of years 1979-2000. The midpoint of that range is 30 years ago.

The earth as a whole is increasing in temperature by ~ 0.2C / decade or ~ 0.6C in the last 30 years. With Arctic amplification, I'll swag it and say the Arctic has increased by ~ 1.5C in the last 30 years. In a normal year (by current standards), the average situation for this image is a significant positive temperature anomaly. We should expect to see a lot of red in this image on a regular basis.

On top of that, we throw in the potential errors in the current GFS model itself as mentioned in my previous post.

The truth is that we probably do have some positive temperature anomaly in the Arctic relative to even recent years, but perhaps not as much "wow" as the image suggests.

Title: Re: The 2020 melting season
Post by: bbr2315 on May 13, 2020, 05:13:08 AM
From Climate reanalyzer, 10 day NH temp anomaly...wow.

Again, for the benefit of those learning....

The GFS image being presented here is comparing forecasted temperatures from the GFS model to the average of years 1979-2000. The midpoint of that range is 30 years ago.

The earth as a whole is increasing in temperature by ~ 0.2C / decade or ~ 0.6C in the last 30 years. With Arctic amplification, I'll swag it and say the Arctic has increased by ~ 1.5C in the last 30 years. In a normal year (by current standards), the average situation for this image is a significant positive temperature anomaly. We should expect to see a lot of red in this image on a regular basis.

On top of that, we throw in the potential errors in the current GFS model itself as mentioned in my previous post.

The truth is that we probably do have some positive temperature anomaly in the Arctic relative to even recent years, but perhaps not as much "wow" as the image suggests.
The errors I mention are re: futurecast and would not apply to re-analysis / hindcast, FYI.
Title: Re: The 2020 melting season
Post by: pearscot on May 13, 2020, 05:18:19 AM
I always recommend reading the forecast of the few weather stations around there. The detailed discussion for Barrow always gives me a better understanding of what's going on in the interior and north of Alaska. It's good for a more broad outlook over just visual references.

for instance:

Quote
.SYNOPSIS...
Very strong high pressure north of the Arctic Coast combined with a weather front over the West Coast and Interior is causing easterly gales of the Arctic Coast along with blowing snow. Expect winds to slowly decrease tonight as the front weakens. This front is causing rain over most of the West Coast south of Kotzebue that
will move west and taper off this evening.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 13, 2020, 05:40:06 AM
I said something about it yesterday and I'm not trying to be rude but who cares what the Euro or the GFS say about surface temps.

It's totally moot when we have an almost cloudless basin which is almost impossible to find anytime of year.

The only thing that matters right now is preconditioning of the basin surface how fast the land snow melts.

The GFS is probably too warm.

But the ESS and laptev gave been above 0C because the surface is wet.

This is so unprecedented.  This surface darkening didn't happen in 2012 until the 6th-12th of JUNE!

IN 2007 IT HAPPENED BETWEEN THE 4TH-9TH OF JUNE.

IN EVERY OTHER YEAR IT HAPPENED AROUND THE 12TH-18TH OF JUNE OR LATER.


CLICK TO ANIMATE!

THE DARKENING HAPPENED FASTER ON THE RUSSIAN SIDE WHERE WAA WAS QUICK.

UNDER THE RIDGE ITS SLOWER BUT HAPPENING THERE JUST FROM DAILY INSOLATION.

AMAZING
Title: Re: The 2020 melting season
Post by: Phoenix on May 13, 2020, 05:49:14 AM
The GFS is probably too warm.

I appreciate your concurrence.

The purpose of my posts are to provide less informed readers some guidance not to put too much faith in the accuracy of GFS forecasts being provided here and on the data thread. Seems you agree that these forecasts are overstating temperatures.
Title: Re: The 2020 melting season
Post by: Phoenix on May 13, 2020, 06:09:44 AM
The cyclone around Svalbard is currently at peak impact at the moment in terms of pushing a shitload of ice toward Fram. If there is any silver lining, it's that the eye of the storm doesn't travel north of Svalbard. Would have made a bad situation worse.

Looking forward to that sucker heading south and getting out of Dodge. It's definitely taking a bite.
Title: Re: The 2020 melting season
Post by: peterlvmeng on May 13, 2020, 06:27:58 AM
Considering blocking pattern, the melting pond will be more and more. The melting pond is a signal of massive melt. The weather of MAY is important to decide the ice compared with June and July. June and July is common high speed melting months. However, the sensitivity of ice is high in May.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 13, 2020, 06:31:16 AM
The GFS is probably too warm.

I appreciate your concurrence.

The purpose of my posts are to provide less informed readers some guidance not to put too much faith in the accuracy of GFS forecasts being provided here and on the data thread. Seems you agree that these forecasts are overstating temperatures.

Yeah it's always done that.

Title: Re: The 2020 melting season
Post by: peterlvmeng on May 13, 2020, 06:46:45 AM
Actually, 2016 also shows an early melting pond in May. Although the summer is cool, it still leads to the second lowest sea ice extent. So I wonder that if the melting pond happens early in MAY it will have a greater chance to break the record even if the summer is not the hottest. However this summer will not be as cool as 2016. Together with the early melting pond, may be the BOE is coming.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 13, 2020, 06:50:09 AM
Considering blocking pattern, the melting pond will be more and more. The melting pond is a signal of massive melt. The weather of MAY is important to decide the ice compared with June and July. June and July is common high speed melting months. However, the sensitivity of ice is high in May.

This is everything.

Historically actual surface ice melt anywhere from 70N+ doesn't take place until July.

With limited bottom ice melt in August between 70-80N.

In the 90s the surface ice melt onset steadily started earlier and earlier.

But the big change first happened in 2007.

Really starting in the fall of 2006 because there was unprecedented loss of MYI into the NATL that winter.

Well almost all of the very limited snowfall in the Arctic basin takes place between September through November..

Between January and April essentially little to no snow falls and what does tends to sublimate.

A lot of the dry Sandy like snow also gets blown into ridges between thicker myi flows that press together essentially forming small 3-20M high mtn ranges of ice.
Or gets blown into the water when floes get roughed up in wind events.

Anyways in 2007 adding to the insult was a ruthless massive top down ridge that blew up right at the start of June that was anomalous from 300MB to the surface meaning dry sinking air that quickly warmed up as soon as surface albedo sank.

This brought us 1.5-2.5CM a day melt from the Beaufort to the ESS on the surface. 

The sun was 24/7 so the subsurface quickly warmed to -1C to 1.5C by the first week of July.

For every 0.5C of warmth about 1CM of ice is lost per day.

So by July first we had 2CM top melt and 2-4CM bottom melt wrecking 3-3.5M ice.

However unlike be every other year on record the ridge didn't break down and vanish.

It weakened but strengthen over and over all summer.

A new normal was born.




My point is even between 2007-2019 the solar energy was mostly moot for melt because albedo, clouds, snow cover, what have you.


Can you imagine if we see widespread surface ice melt by the 20th-25th of May instead of getting established after June 15th.

That's 3 weeks of extra melt that's 3 weeks of early July level solar energy not being floated back to space by 0.85 albedo versus 0.55-0.60 albedo where 2-3X more energy is not only melting ice but warming the ice to the melt point and warning the sub surface.

Many of us have preached for years it will take a May solar beating like June 07 to blow by 2012 like 07 blew by 2005.



Title: Re: The 2020 melting season
Post by: thejazzmarauder on May 13, 2020, 06:53:51 AM
Actually, 2016 also shows an early melting pond in May. Although the summer is cool, it still leads to the second lowest sea ice extent. So I wonder that if the melting pond happens early in MAY it will have a greater chance to break the record even if the summer is not the hottest. However this summer will not be as cool as 2016. Together with the early melting pond, may be the BOE is coming.
2016 could end up being a good analog. Early melt ponding is clearly favorable for ice loss later in the season, and if the ice is sufficiently pre-conditioned over the next week, we could set an extent low this year. That said, a BOE is still unlikely; the ice is too thick in too many places. Maybe I'm wrong.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 13, 2020, 07:02:24 AM
Actually, 2016 also shows an early melting pond in May. Although the summer is cool, it still leads to the second lowest sea ice extent. So I wonder that if the melting pond happens early in MAY it will have a greater chance to break the record even if the summer is not the hottest. However this summer will not be as cool as 2016. Together with the early melting pond, may be the BOE is coming.

Not sure when May 2016 kicked off but up to the 12th it was cloudy in 2016.

By the 18 of May 2016 some clearing was evident but only showed up for one day and only the far Southern ESS had any surface melting.

After that it was cloudy all over until the 1st of June with the ESS showing some melt and then it's cloudy again after until at least June 10th.


The amount of clearing we have right now is so jacked up its a pinch me is this real?

I guarantee you scientists AT NSIDC, HAMBURG, BREMEN, MOSIAC, JAXA, IARC, PIOMAS, ESA, NASA, CSA AND SO ON ARE ALL LOOKING AT THIS GOING OH SH$#
Title: Re: The 2020 melting season
Post by: jdallen on May 13, 2020, 07:13:15 AM
I agree with friv, and think one additional ingredient here is the amount of ice that will be sent down the death zone past Svalbard and out the Fram strait. We're looking at 4+ days of strong surface winds exporting ice. Just look at how packed the isobars are on this output and how well they are positioned to export ice.

That ain't no joke that is crazy you're going to see open water come in the kara or the laptev because of all this

Chiming in.

Add Ekman pumping.  The ice is far more mobile than previous years, so it will not prevent transfer of force from the wind to the water below.  We should see significant mixing of the column under those regions where the wind in this dipole are *already* at work.  The CAB immediately north of Svalbard will be shattered more thoroughly than we would normally see before July.

The High combined with the storm over Svalbard create a near perfect hammer and anvil to shatter the Arctic.  The only question remaining is just how severe the damage will be.

To underscore what Friv said earlier about albedo,  we are talking about conditions being created (dropping albedo from 85 down to 60) which will more than double the amount of insolation being captured by the ice.   It will be doing that about a month earlier than typical, during increasing insolation.

Certainly we've seen ice get beaten up with lowered albedo, but mostly that is happening after the solar peak in late June, so the ice is basically riding the end of a wave (diminishing insolation) after it's broken.

We may be about to see that equation shifted a full month, so that those late July conditions are reached in late June instead - at peak insolation. In short, the ice will be getting pulled into the "wave" of insolation just as it's breaking, with pretty serious consequences.

If that happens, it will be hard *not* to overtake the 2012 extent and area losses. 
Title: Re: The 2020 melting season
Post by: aperson on May 13, 2020, 07:20:31 AM
Environment Canada's 2020-05-12 18z Analysis put the high at 1043mb and the low at 958mb. An 85mb gradient, impressive!
Title: Re: The 2020 melting season
Post by: Phoenix on May 13, 2020, 09:09:07 AM
winds peaking at 58 kts along the coast of ne greenland.  :o
Title: Re: The 2020 melting season
Post by: blumenkraft on May 13, 2020, 10:22:03 AM
But the ESS and laptev gave been above 0C because the surface is wet.

QED!

Meltponding in the north-west of Wrangel Island!
Title: Re: The 2020 melting season
Post by: peterlvmeng on May 13, 2020, 11:54:45 AM
The positive AO has last for almost four months. The AO will be likely negative in the coming months considering the balancing of statistical average. Another factor is ocean temperature although influenced by the solar energy. The sea surface temperature is governed by the weather. The deep water is governed by the AMOC. I am not sure whether the current will be helpful in melting the sea ice.
Title: Re: The 2020 melting season
Post by: Csnavywx on May 13, 2020, 12:58:30 PM
The GFS is probably too warm.

I appreciate your concurrence.

The purpose of my posts are to provide less informed readers some guidance not to put too much faith in the accuracy of GFS forecasts being provided here and on the data thread. Seems you agree that these forecasts are overstating temperatures.

I feel a need to chime in here. I use these models on a daily basis as a meteorologist.

The FV3-GFS was released last June and resulted in some major changes to the way the model handles surface temperatures. The net result left the model with a temporally increasing cold bias (the most severe at longer lead times).

This is less in the last 7 days (-0.25C over the Arctic Ocean), but still present as of now.

It can be useful (at the micro or mesoscale) to compare surface stations to model temperatures, but keep in mind that most modeling assimilates the majority of the data they use from satellites. The lack of surface stations used to be an issue, but with the advent of much higher quality and density of remote sensing from satellites, this has changed significantly.

If there's a difference in output between the GFS and EC in the short range, that's due to differences in how those two models assimilate and handle bias correction. Based on the obvious surface melting signature from MODIS on worldview though, we can surmise that at least the short-range forecasts from the GFS have been verifying well over the Chukchi/ESS/Laptev wrt the extent of above freezing temperatures.
Title: Re: The 2020 melting season
Post by: be cause on May 13, 2020, 01:08:23 PM
Thank you Csnavywx .. glad to have you corroborate . b.c.
Title: Re: The 2020 melting season
Post by: Paladiea on May 13, 2020, 01:11:14 PM
The positive AO has last for almost four months. The AO will be likely negative in the coming months considering the balancing of statistical average. Another factor is ocean temperature although influenced by the solar energy. The sea surface temperature is governed by the weather. The deep water is governed by the AMOC. I am not sure whether the current will be helpful in melting the sea ice.

Actually I was just pondering this, and it seems like the AMOC is experiencing a negative feedback in terms of affecting the Arctic ice. This is probably because it's expending most of the energy that normally would go into the Arctic on Greenland's ice. Following this reasoning, I'd expect the AMOC to have less and less of an impact on the Arctic as the years progress.
Title: Re: The 2020 melting season
Post by: Phoenix on May 13, 2020, 01:16:50 PM

The amount of clearing we have right now is so jacked up its a pinch me is this real?

I guarantee you scientists AT NSIDC, HAMBURG, BREMEN, MOSIAC, JAXA, IARC, PIOMAS, ESA, NASA, CSA AND SO ON ARE ALL LOOKING AT THIS GOING OH SH$#

We are all going, "OH SH$#". Now that we are belatedly realizing that the fate of humanity has been dependent on cloud cover in the Arctic in May. Where did I put that bucket list.....



Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 13, 2020, 01:24:08 PM
I agree with friv, and think one additional ingredient here is the amount of ice that will be sent down the death zone past Svalbard and out the Fram strait. We're looking at 4+ days of strong surface winds exporting ice. Just look at how packed the isobars are on this output and how well they are positioned to export ice.

That ain't no joke that is crazy you're going to see open water come in the kara or the laptev because of all this

Chiming in.

Add Ekman pumping.  The ice is far more mobile than previous years, so it will not prevent transfer of force from the wind to the water below.  We should see significant mixing of the column under those regions where the wind in this dipole are *already* at work.  The CAB immediately north of Svalbard will be shattered more thoroughly than we would normally see before July.

The High combined with the storm over Svalbard create a near perfect hammer and anvil to shatter the Arctic.  The only question remaining is just how severe the damage will be.

To underscore what Friv said earlier about albedo,  we are talking about conditions being created (dropping albedo from 85 down to 60) which will more than double the amount of insolation being captured by the ice.   It will be doing that about a month earlier than typical, during increasing insolation.

Certainly we've seen ice get beaten up with lowered albedo, but mostly that is happening after the solar peak in late June, so the ice is basically riding the end of a wave (diminishing insolation) after it's broken.

We may be about to see that equation shifted a full month, so that those late July conditions are reached in late June instead - at peak insolation. In short, the ice will be getting pulled into the "wave" of insolation just as it's breaking, with pretty serious consequences.

If that happens, it will be hard *not* to overtake the 2012 extent and area losses.

Absolutely nailed what is at stake attm.

Just browsing through Modis looking at when the majority of the Arctic basin went from dry/semi dry surface to wet by year.

With about 80 percent being the magic mark.

The data runs from 2000-present

2000- third week July
2001- third week July
2002- second week July
2003- last week June
2004-first week July
2005- third week of June(had huge sunny skies basin wide in mid June)
2006-July first week
2007- first week June
2008- second week June(mid May Western CAB/Beaufort
2009- third & fourth week June
2010- between first and second week June
2011-second week June
2012- end of first week June
2013- end of June
2014-end of June/first week of July
2015-third to fourth week June
2016-third week June
2017-first week July
2018-fourth week June
2019- end of June early July

2020- ????


Notice not one year has May.

Why?

We have never had a basin wide sunny wall to wall ridge between 15th-30th of May.

The major ridging has appeared in early June.

It might be to early to see the surface albedo collapse.

And by the time this pattern changes we might be already to early to have made a basin wide dent.

However from the pole to the Chuchki, ESS, laptev, Kara, and Atlantic side will see albedo drop from this.

The question is how far well that penetrate towards the CAB.

Imagine if this pattern evolves into a dipole anomaly the last week of May that holds 2007 style into deep June.

That is how we have a basin wide collapse of the remaining ice structure.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 13, 2020, 01:45:52 PM
I also want to say there is decent correlation between nuetral Enso conditions towards weak Nina that correlates with the negative AO, negative NAO summers of 05, 07-12...

It's not perfect 1996 had the most anomalous vortex in the modern record with nuetral/weak Nina.

We have had a weak Oni nino through March.

However real time conditions are going straight towards a big Nina event.

Does that matter?

I don't know .

Why did we have 05, 07-12 with historic dipole ridging during the summer months and anchored over GIS.

We have had major ridging events like 2015 July the warmest July on record in the Arctic that semi-extended to GIS.

However after 2015 we have been far more reliant on huge WAA incursions from land to decimate ice versus good ole sun bathing of the golden era 05-12 minus 06 and 09.

2009 had dipolish but 2009 had above normal snow cover that retarded the major surface heating.

2011 on the other hand had almost no snow cover all over so the Southern CAB almost bit the dust

My two favorite thickness images ever


I HAVE HAD TO SCREAM FROM THE MOUNTAIN TOPS TO GET 2011 THE RECOGNITION IT DESERVES.

April 2011 not much thickness in the CAB but 2.5-3.5M

And May typically sees ice thickening above 80N.

But holy smokes...if 2011 didn't have August go cloudy and cold.

Like when did all that CAB ice melt?

Anytime it was warm enough because by early June snow cover was gone over most of the cab.

Was there a major fire at some point darkening the cab?

This is why we desperately need a reliable snow thickness in the Arctic.

I want to see a total ice collapse so maybe funding will go back into satellite and buoy expenses.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 13, 2020, 01:47:22 PM

The amount of clearing we have right now is so jacked up its a pinch me is this real?

I guarantee you scientists AT NSIDC, HAMBURG, BREMEN, MOSIAC, JAXA, IARC, PIOMAS, ESA, NASA, CSA AND SO ON ARE ALL LOOKING AT THIS GOING OH SH$#

We are all going, "OH SH$#". Now that we are belatedly realizing that the fate of humanity has been dependent on cloud cover in the Arctic in May. Where did I put that bucket list.....

 Lol no but most of us live for anomalous events never seen before.

I'd like to see what it will take to collapse the basin ice near melt out.
Title: Re: The 2020 melting season
Post by: PragmaticAntithesis on May 13, 2020, 02:47:03 PM
<nested quotes snipped>

Absolutely nailed what is at stake attm.

Just browsing through Modis looking at when the majority of the Arctic basin went from dry/semi dry surface to wet by year.

With about 80 percent being the magic mark.

The data runs from 2000-present

2000- third week July
2001- third week July
2002- second week July
2003- last week June
2004-first week July
2005- third week of June(had huge sunny skies basin wide in mid June)
2006-July first week
2007- first week June
2008- second week June(mid May Western CAB/Beaufort
2009- third & fourth week June
2010- between first and second week June
2011-second week June
2012- end of first week June
2013- end of June
2014-end of June/first week of July
2015-third to fourth week June
2016-third week June
2017-first week July
2018-fourth week June
2019- end of June early July

2020- ????


Notice not one year has May.

<snip>

There may be no Mays, but 2007, 2010(?) and 2012 got first week of June, which is pretty close! Even if the albedo drop technically breaks into May, it won't be much worse than 2007. Not exactly comforting, but only barely going into uncharted waters is a lot better than being tossed in the ocean!
Title: Re: The 2020 melting season
Post by: Phoenix on May 13, 2020, 02:51:54 PM
Lol no but most of us live for anomalous events never seen before.

I'd like to see what it will take to collapse the basin ice near melt out.

Your enthusiasm for anomalous events is duly noted and entertaining Friv. And I totally appreciate and respect your contributions to the subject matter here.

At this point, in terms of the expectations of the readers of this thread, avoiding a BOE may be a more anomalous outcome than seeing a BOE. It would be anomalous in terms of humans getting their act together and proactively addressing a problem.

Selfishly, I hope that your wish to see an Arctic melt out goes unfulfilled. Nothing personal. Just pulling for a different kind of anomaly.
Title: Re: The 2020 melting season
Post by: Phoenix on May 13, 2020, 03:05:47 PM
According to Windy.com, the max wind speeds per the ECMWF on the NE Greenland coast are now 85 knots. That's 98 mph or equivalent to a class 2 hurricane.

I'm not big on hyperbole, but this isn't funny. Have a look.

https://www.windy.com/-Wind-gusts-gust?gust,80.069,-6.372,5,m:fTAaftZ
Title: Re: The 2020 melting season
Post by: gerontocrat on May 13, 2020, 03:22:45 PM
Last season I certainly remember GFS continually forecasting great warm events in the Arctic in their 5-10 day forecast that very frequently did not happen. One / two days later the event just was not there in their forecasts.

Since the upgrade my anecdotal evidence is that GFS is doing better. Last week I took their longer-term forecasts more seriously simply because those forecasts remained mostly unchanged as the days went by, and reality is currently pretty close to those forecasts from a week ago.

You never know, we might have to start taking the 5-10 day forecasts seriously. After all, a helluva lot of cash and time has been put into the met systems - so they should do better.



Title: Re: The 2020 melting season
Post by: SimonF92 on May 13, 2020, 03:23:45 PM
Bottom melt?  :-X
Title: Re: The 2020 melting season
Post by: Freegrass on May 13, 2020, 04:25:47 PM
Five Day Forecast
Wind + Temp @ Surface

Besides the high temperatures on the ice, the arctic seems to calm down again in the coming week. So this is the last one until the next big event.

High temperatures are reaching all the way to the coast of Siberia, so it looks like the snow there will be mostly gone by the end of the week.

Enjoy...
Title: Re: The 2020 melting season
Post by: Freegrass on May 13, 2020, 05:03:44 PM
Barents sea ice on May 4, and today.  ???

https://go.nasa.gov/2T4lEFP
Title: Re: The 2020 melting season
Post by: Burnrate on May 13, 2020, 06:19:45 PM
We won't sea ice pretty soon.
Title: Re: The 2020 melting season
Post by: Phoenix on May 13, 2020, 06:31:38 PM
Last season I certainly remember GFS continually forecasting great warm events in the Arctic in their 5-10 day forecast that very frequently did not happen. One / two days later the event just was not there in their forecasts.

Since the upgrade my anecdotal evidence is that GFS is doing better. Last week I took their longer-term forecasts more seriously simply because those forecasts remained mostly unchanged as the days went by, and reality is currently pretty close to those forecasts from a week ago.

You never know, we might have to start taking the 5-10 day forecasts seriously. After all, a helluva lot of cash and time has been put into the met systems - so they should do better.

How are you defining reality in the Arctic Ocean ? There aren't a lot of actual thermometers taking measurements there.
Title: Re: The 2020 melting season
Post by: blumenkraft on May 13, 2020, 06:40:21 PM
As mentioned by Csnavywx earlier today, it's Satellites helping us out, Phoenix.   :)

In other news, Polarstern readings and GFS are very much in agreement that it's -0.3˚C there today.

Edit: Oops, missed the minus. Thanks, Uniquorn for the correction
Title: Re: The 2020 melting season
Post by: oren on May 13, 2020, 06:42:30 PM
Let's not get bogged down in the discussion on GFS long-term forecast reliability. It can be continued elsewhere. And bear in mind newbies and lurkers are not easily misled, especially after reading several warnings on the same issue.
Title: Re: The 2020 melting season
Post by: uniquorn on May 13, 2020, 08:03:32 PM
that's -0.3C at Polarstern (https://www.sailwx.info/shiptrack/shipposition.phtml?call=DBLK)  :)
+0.4C from nullschool (https://earth.nullschool.net/#2020/05/13/1800Z/wind/surface/level/overlay=temp/orthographic=-45.46,87.22,3000/loc=10.2,83.4) (to the nearest hour)

To save endless discussion, someone could document nullschool temperature for Polarstern coordinates since october (https://www.sailwx.info/shiptrack/shipposition.phtml?call=DBLK) and produce the figures (not me). Or from now on would still be useful.
Scroll down to the bottom of the sailwx page and click on track history

max wind speed for PS today was 45kt, 83.34km/hr
Title: Re: The 2020 melting season
Post by: Csnavywx on May 14, 2020, 04:54:19 AM
Last season I certainly remember GFS continually forecasting great warm events in the Arctic in their 5-10 day forecast that very frequently did not happen. One / two days later the event just was not there in their forecasts.

Since the upgrade my anecdotal evidence is that GFS is doing better. Last week I took their longer-term forecasts more seriously simply because those forecasts remained mostly unchanged as the days went by, and reality is currently pretty close to those forecasts from a week ago.


You never know, we might have to start taking the 5-10 day forecasts seriously. After all, a helluva lot of cash and time has been put into the met systems - so they should do better.

How are you defining reality in the Arctic Ocean ? There aren't a lot of actual thermometers taking measurements there.

Most data ingestion and assimilation is from satellites (see earlier post).
Title: Re: The 2020 melting season
Post by: Csnavywx on May 14, 2020, 04:57:22 AM
Last season I certainly remember GFS continually forecasting great warm events in the Arctic in their 5-10 day forecast that very frequently did not happen. One / two days later the event just was not there in their forecasts.

Since the upgrade my anecdotal evidence is that GFS is doing better. Last week I took their longer-term forecasts more seriously simply because those forecasts remained mostly unchanged as the days went by, and reality is currently pretty close to those forecasts from a week ago.

You never know, we might have to start taking the 5-10 day forecasts seriously. After all, a helluva lot of cash and time has been put into the met systems - so they should do better.

That changed when the GFS was upgraded to the FV3-GFS on June 12, 2019. It's often been running a cold bias since then.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 14, 2020, 05:13:29 AM
Barents sea ice on May 4, and today.  ???

https://go.nasa.gov/2T4lEFP

Pretty noticeable change

Although that ice according to smos was only a .25M thick anyways.

Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 14, 2020, 05:19:06 AM
Last season I certainly remember GFS continually forecasting great warm events in the Arctic in their 5-10 day forecast that very frequently did not happen. One / two days later the event just was not there in their forecasts.

Since the upgrade my anecdotal evidence is that GFS is doing better. Last week I took their longer-term forecasts more seriously simply because those forecasts remained mostly unchanged as the days went by, and reality is currently pretty close to those forecasts from a week ago.

You never know, we might have to start taking the 5-10 day forecasts seriously. After all, a helluva lot of cash and time has been put into the met systems - so they should do better.

How are you defining reality in the Arctic Ocean ? There aren't a lot of actual thermometers taking measurements there.

There is the MOSIAC and the are currently 7 buoys in the Western CAB/Beaufort currently reporting surface temps.

Plus all of the twice a day weather ballon soundings along the Arctic coast. 

There are 5 of them along the Eurasian coast.  Plus 3 more on islands.

We have a weather station on Wrangel island.

There is Barrow Alaska, another along the Mackenzie Delta, eureka, alert, resolute, weather stations on the parry island or whatever its called.

There is like 6-7 along GIS.


So plenty of data up there.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 14, 2020, 05:21:19 AM
As mentioned by Csnavywx earlier today, it's Satellites helping us out, Phoenix.   :)

In other news, Polarstern readings and GFS are very much in agreement that it's -0.3˚C there today.

Edit: Oops, missed the minus. Thanks, Uniquorn for the correction

Which makes sense.

Check out the two day surface brightness change.

That's a lot of darkening over the central Arctic basin in two days from the 11-13th.


CLICK TO ANIMATE.



Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 14, 2020, 05:25:01 AM
Bottom melt?  :-X


Where is that?

That shows like 12-15CM of snow.

Which is nothing
Title: Re: The 2020 melting season
Post by: Freegrass on May 14, 2020, 05:28:03 AM
Barents sea ice on May 4, and today.  ???

https://go.nasa.gov/2T4lEFP (https://go.nasa.gov/2T4lEFP)

Pretty noticeable change

Although that ice according to smos was only a .25M thick anyways.
True. That was a lot of loose rubble there. But still... that's a lot of ice that's gone so early in the season...

It'll be more interesting to see how much of the thick ice that got piled up against Svalbard will get flushed down the Fram... I think that'll be all gone by now...
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 14, 2020, 10:32:57 AM
Pevek Russia still torching.

Another record high on the 13th.  That's 3 in 6 days.

Title: Re: The 2020 melting season
Post by: Aluminium on May 14, 2020, 10:34:44 AM
May 9-13.

2019 (https://forum.arctic-sea-ice.net/index.php/topic,2591.msg199202.html#msg199202).
Title: Re: The 2020 melting season
Post by: uniquorn on May 14, 2020, 12:59:13 PM
Bottom melt?  :-X
Where is that?
That shows like 12-15CM of snow.
Which is nothing
Estimation of Mosaic Thermistor buoy ice and snow depth (https://forum.arctic-sea-ice.net/index.php/topic,3013.0.html). Snow depth turns out to be tricky to calculate from temperature readings alone.
Here are some details of snow depth at deployment (https://data.meereisportal.de/gallery/index_new.php?active-tab1=method&buoytype=TB&region=all&buoystate=active&expedition=MOSAiC&buoynode=all&submit3=display&lang=en_US&active-tab2=buoy) of mosaic buoys during april, many of which are much less than 'nothing'
Drift animation shows rough location of the mosaic buoy array, though it is larger (https://forum.arctic-sea-ice.net/index.php/topic,2906.msg257204.html#msg257204) than the 3 buoys shown. Svalbard bottom right.
Title: Re: The 2020 melting season
Post by: Aluminium on May 14, 2020, 03:21:55 PM
Something happens this year. Lack of snow in Siberia leads to extreme heatwaves there. And this heat may reach the Arctic Ocean.
Title: Re: The 2020 melting season
Post by: Niall Dollard on May 14, 2020, 06:25:03 PM

To save endless discussion, someone could document nullschool temperature for Polarstern coordinates since october (https://www.sailwx.info/shiptrack/shipposition.phtml?call=DBLK) and produce the figures (not me). Or from now on would still be useful.


I have done some comparison (last 48hrs) and to avoid clutteriing this thread, I have placed the results in this thread.

https://forum.arctic-sea-ice.net/index.php/topic,3084.0.html
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 14, 2020, 06:47:16 PM
I really miss the Npole Cam.

I wish this community was big enough that we could afford to pool our money together and have a surface only buoy that didn't have any sub surface instruments that made it to delicate.

A surface only one could be made so it sat on a ovalish platforn that could float or be partially or fully embed in ice and the center part could move say upwards of 30-45° from a 0° center mass to always stay balanced and upright.

And that center elongated rectangular block would house a digital weather station that would have sensors for temp wind, humidity, and irradiance measuring.

This block would be 2M high from it's base where it meets the oval base.

The oval base would be waterproof.  Because it would be housing the huge think Tesla like battery. Probably not as big but something that could be fully charged by fall and operate all winter.

The oval base would have to be big enough to have solar panels built in that would be slightly curved with the base shape but also have lightweight tubing underneath that could push the panel up at the top so the panel meets the 25-35° solar altitude for battery charging and direct Power to run the two 4K video cams that could record up to 120 fps in raw output that can be post processed to handle the solar reflection and not be blown out.


And if we really got some $$.

We could have a very sturdy built quad drone that would also carry a 4 or 8k camera that would record at least 30fps.

And could land and dock INSIDE the base and recharge while also housing the computer tech to remotely upload the data iideally on starlink and not some super expensive legacy connection.

How much would it cost us to have this designed, tested and built.


We would really want this to run for 5-7 years hopefully 10.

If it happens to float out the fram we can have it picked up and refitted, refurbished with better tech and sent back to the Beaufort.

It's very clear to me that the first world governments and science agencies won't even bother with this kind of text
Tech even under 200k

Hopefully with the falcon heavy being cheaper and cheaper the costs for next gen remote sensing can go down.

For instance the modis/amsr2 1km/5km Sia product is amazing.

Expecially on days where the basin is clear and that 1km modis resolution is used


THOUGHTS

Title: Re: The 2020 melting season
Post by: pearscot on May 14, 2020, 07:11:28 PM
I think it would be very possible to build something fully autonomous to do a lot of that. I highly recommend you check the youtube channel RC Test Flight. His work is amazing and he 3d prints his own autonomous rovers/solar powered planes. Really, the hardest thing I foresee is keeping the batteries warm enough to hold a charge in the winter. If there's one thing batteries hate, it's extreme cold.

Anyways, it looks like it's fairly clear over a large swath of the Arctic. I keep expecting to see more melt in the Bearing Strait, but I can't figure out what is going on there.

I would like to add this, as the wind has certainly played a role. I also think this emphasized just how mobile the entire pack is right now:

Title: Re: The 2020 melting season
Post by: oren on May 14, 2020, 08:59:11 PM
Friv, I wholeheartedly agree. The forum, some sponsor, some university, some billionaire, some country, some organization, humanity, should be filling the Arctic sea ice and the Antarctic and Greenland glaciers with devices to measure and photo them in various ways. Billions and trillions available for banks and oilmen but very little if anything for real-time localized Cryosphere monitoring.
We an discuss the achievable technical details, tradeoffs, and some fantasies, But not on this thread. Some existing or new buoy thread should be the proper venue.
Title: Re: The 2020 melting season
Post by: Freegrass on May 14, 2020, 09:46:39 PM
The only way is up!  ???

I've added 2019 and 2016 for comparison. These temperatures are highly unusual. The only year that is comparable is 2006 (last image), but I don't remember 2006 as being a disaster for the ice...
Title: Re: The 2020 melting season
Post by: gerontocrat on May 14, 2020, 09:56:57 PM
Friv, I wholeheartedly agree. The forum, some sponsor, some university, some billionaire, some country, some organization, humanity, should be filling the Arctic sea ice and the Antarctic and Greenland glaciers with devices to measure and photo them in various ways. Billions and trillions available for banks and oilmen but very little if anything for real-time localized Cryosphere monitoring.
We an discuss the achievable technical details, tradeoffs, and some fantasies, But not on this thread. Some existing or new buoy thread should be the proper venue.
I thought of an "If only........" thread, and after a few seconds contemplation it became hhhuuuuggge.
Title: Re: The 2020 melting season
Post by: uniquorn on May 14, 2020, 10:10:43 PM
uni-hamburg amsr2-uhh, bering/chukchi, apr1-may13
Title: Re: The 2020 melting season
Post by: igs on May 14, 2020, 11:16:28 PM
The only way is up!  ???

I've added 2019 and 2016 for comparison. These temperatures are highly unusual. The only year that is comparable is 2006 (last image), but I don't remember 2006 as being a disaster for the ice...


It's all about permanent relentless pre-conditioning until the hammer falls.


After 2006 came 2007 and i'd be surprised if 2006 didn't have an impact on 2007 events.


Only that the hammer fell on solid ground in 2007 while the next one will hit japanese paper walls.
Title: Re: The 2020 melting season
Post by: gandul on May 15, 2020, 12:32:19 AM

THOUGHTS
You're asking for MONEY more than thoughts...  If there's no billionaire among us, ask Elon for... a disappointment
Title: Re: The 2020 melting season
Post by: Freegrass on May 15, 2020, 12:58:02 AM
uni-hamburg amsr2-uhh, bering/chukchi, apr1-may13
I just went back through the days again on Nullschool - because I couldn't remember a strong southern wind blowing through the Bering Strait in the last few weeks - and it turns out my memory didn't abandon me. Winds were mostly northerlies, or absent. So I'm curious now why all that ice got "pulled" into the Chukchi sea. It can't be because of the current, can it? That would be a strong current... So could it be "suction" from a retreating Ice pack? I can't figure it out...
Title: Re: The 2020 melting season
Post by: Steerpike on May 15, 2020, 07:49:48 AM
Much less snow cover south of the Yamal peninsula this year, no doubt due to the very mild winter there this year.
Title: Re: The 2020 melting season
Post by: pauldry600 on May 15, 2020, 08:28:18 AM
Dont really post often but to me all sides of Arctic are getting hit now. Looks dangerously fragile. We are in the top 4 these past few weeks and will probably stay there. Places that have never melted out will probably melt out this year but 2012 will remain the outlier.
Title: Re: The 2020 melting season
Post by: Pavel on May 15, 2020, 09:00:31 AM
Of course it's not reliable, but GFS supposes  Eurasia will lost much of its remaining snow by May 25. Also huge areas of the Beaufort, Chuckchi, ESS, Laptev sea ice will also lose snow what mean ice turning blue
Title: Re: The 2020 melting season
Post by: kiwichick16 on May 15, 2020, 09:02:24 AM
@  pauldry600......2012 may remain at outlier....but for how much longer?

Current CO2 @  Mauna Loa  416 ppm

34 ppm to 450 ppm  ….. 3ppm  per year x  11.333 years = 34 ppm

450 ppm = Tipping Point ???
Title: Re: The 2020 melting season
Post by: johnm33 on May 15, 2020, 11:46:10 AM
It can't be because of the current, can it? That would be a strong current... So could it be "suction" from a retreating Ice pack? I can't figure it out...
My take is that the dipole, high mslp over practically the whole basins area has persisted for long enough to force water out of Fram. The easiest fraction to move is the layer beneath that held still by the ice keels but that upper layer with the ice also seems to be moving generally towards Fram. The losses will be exaggerated by tidal forcings meaning that excess has to be replaced from somewhere so Atlantic waters deep through Fram and via Barents into St.Anna>Laptev and Pacific waters via Bering.
Some of the papers/presentations (https://forum.arctic-sea-ice.net/index.php/topic,3080.0.html) recently linked by Nukefix are relevant to this well worth the time.
Title: Re: The 2020 melting season
Post by: Wildcatter on May 15, 2020, 12:31:11 PM
Looking at the nasa over the last few days, aluminums gif, and the forecast. ESS might look pretty interesting in a week, might get punished for not eating its vegetables this winter (volume), more cracking with wind and ice movement.

could have cracking all around the "shell" (coasts), like the beaufort ones with continued southerlies. kara. the anti-cyclonic winds also seem to help spur ice retreat in the bering. FJL ice on the Atlantic side too, that one will probably close up but there's a lot of wind forcing and it's moved quite a bit just the last few days, then the big ol' cyclone comes in over the barents, good chunk of volume sitting next to it and svalbard

east eurasia heat might be worth watching, looks like its tired of being cold. and then all the fram/atlantic export, will be an interesting week

yikes. the heat across Eurasia really starts to "stick" at high latitudes in the next few days. this is probably going to be a problem before we even get to the end of may. will be interesting to see the effects of that + emergence of the "laptev bite" + unfortunate albedo conditions of the ESS + Laptev with the ESS already not looking great and record low volume across the area. not really sure how much of the Kara is even going to survive May either

don't be surprised if we see abnormally large amounts of melt in the Hudson in the next two weeks.

looks like Bering and Chukchi water will connect in just a few days. how much melt we see in the chukchi by the end of may is anyone's guess. Beaufort only a matter of time, heat and probably wind forcing will find a way to get to it enough in the next 2 weeks to set up for June.

rough estimate, we need about 58k/day average extent loss to pass 2019 on May 28, for second place. That's also about the amount needed, on average, to pass 2016 on June 9, for first place, in "extent" anyway. Looks like that's a fairly good possibility
Title: Re: The 2020 melting season
Post by: El Cid on May 15, 2020, 03:33:06 PM


Current CO2 @  Mauna Loa  416 ppm

450 ppm = Tipping Point ???

There is NO exact tipping point. This is a freight train, things are in motion which can not really be stopped. Even if we today ended all Co2 emissions, we would see the Arctic melt out - at least that is what I think having read a good many studies on paleoclimate.

We need to reduce CO2 emissions not because then the Arctic wouldnt melt out (I believe it would) but to avoid a complete climate-disaster.

This year is very similar to 2007, just like this winter was very similar to 2006-7. Friv's pics are pretty ominous: this season starts out very strong
Title: Re: The 2020 melting season
Post by: Phil. on May 15, 2020, 04:25:52 PM
NSIDC Area data (continued)

One oddity that is continuing is that
- area loss in the periphery now below average,
- area loss in the high Arctic now above average.

Not sure what that means (if anything). Ice in the Central seas (literally) in rotten shape?

Wondering if the gale up there has blown more out the Fram and added to the peripheral but depleted the central?
Title: Re: The 2020 melting season
Post by: Freegrass on May 15, 2020, 04:41:42 PM
It can't be because of the current, can it? That would be a strong current... So could it be "suction" from a retreating Ice pack? I can't figure it out...
My take is that the dipole, high mslp over practically the whole basins area has persisted for long enough to force water out of Fram. The easiest fraction to move is the layer beneath that held still by the ice keels but that upper layer with the ice also seems to be moving generally towards Fram. The losses will be exaggerated by tidal forcings meaning that excess has to be replaced from somewhere so Atlantic waters deep through Fram and via Barents into St.Anna>Laptev and Pacific waters via Bering.
Some of the papers/presentations (https://forum.arctic-sea-ice.net/index.php/topic,3080.0.html) recently linked by Nukefix are relevant to this well worth the time.
Thanks for those papers John! I'll have a look at them later.

In reply to another message; The "tipping point" was 350 ppm, so all that can save us now is to get that CO2 back out of the atmosphere. But that's for another thread...
Title: Re: The 2020 melting season
Post by: P-maker on May 15, 2020, 04:50:11 PM
Yeah - give us the number. Is the Greenland Sea finallly approaching the 1 mio. sq. km mark? If yes, this will explain some of the discrepancies, but it will not bode well for the remaining part of the melt century.
Title: Re: The 2020 melting season
Post by: paolo on May 15, 2020, 04:58:37 PM
Pevek thaw 15-05-2020
the port is already free
Title: Re: The 2020 melting season
Post by: pearscot on May 15, 2020, 05:26:11 PM
Certainly the area above Greenland and down to Svalbard have been stuck stuck in the clouds and dealing with a low for the past bit, but AGAIN it's another clear day for a lot of the pack.

Is this normal? I don't get the sense that it is, or at least this time of the year. Granted it's still somewhat cold atop, but it's crazy to see how much sun the area in general is getting. I can only imagine that every tiny bit of open water and darkening spots will just continue to absorb more and more energy. Very interesting season...
Title: Re: The 2020 melting season
Post by: Burnrate on May 15, 2020, 06:24:12 PM

...
Is this normal? ...

Perhaps the reduced aerosols are contributing to the reduced cloud cover more than would be expected.  I don't know much about the specifics there but maybe the relationship between aerosol density and cloud formation isn't linear or continuous.
Title: Re: The 2020 melting season
Post by: bbr2315 on May 15, 2020, 06:29:54 PM

...
Is this normal? ...

Perhaps the reduced aerosols are contributing to the reduced cloud cover more than would be expected.  I don't know much about the specifics there but maybe the relationship between aerosol density and cloud formation isn't linear or continuous.
I would think that besides the ~1/3 reduction in global aerosols (I could be grossly off o this # but I think it is reasonable), the 90% drop in air traffic is the biggest contributor to the lack of clouds. Or, the drop in air traffic at this point may be taking primacy even over the drop in aerosols. There was a study after 9/11 that showed a major rise in temperatures when air traffic halted. This is now being replicated much more severely across the entire planet.
Title: Re: The 2020 melting season
Post by: pearscot on May 15, 2020, 06:30:12 PM

...
Is this normal? ...

Perhaps the reduced aerosols are contributing to the reduced cloud cover more than would be expected.  I don't know much about the specifics there but maybe the relationship between aerosol density and cloud formation isn't linear or continuous.

Yeah, it is interesting. I've been watching the changes unfold during May on worldview and am quite surprised by the amount of ice mobility. Additionally, I did compare the last 15 days of ice export out of the Fram Strait and it certainly is elevated. Some large chunks of ice are now moving steadily south and off the coast of Greenland. I suspect the storm in the area north of there is the largest driver of it.
Title: Re: The 2020 melting season
Post by: Downpuppy on May 15, 2020, 07:16:14 PM
Peripheral area now is all about the Hudson. It was pretty cold there last week, not so much now. Once this concentration reduction in the center hits the 5 day averages, it should plunge.
Title: Re: The 2020 melting season
Post by: Freegrass on May 15, 2020, 07:45:09 PM
That arm of fast ice that was sticking out of the north of Greenland towards the Fram, didn't survive the latest storm...
Title: Re: The 2020 melting season
Post by: Freegrass on May 15, 2020, 08:04:54 PM
Something's moving north of Ellesmere in the last three days...

https://go.nasa.gov/36egM6t
Title: Re: The 2020 melting season
Post by: pearscot on May 15, 2020, 08:13:45 PM
Something's moving north of Ellesmere in the last three days...

https://go.nasa.gov/36egM6t

Ha, I was LITERALLY just looking at that entire region. Granted, massive ice fractures in that region are normal, but the change over this ~2 day period are wild. There's a whole lot going on in the Arctic right now...
Title: Re: The 2020 melting season
Post by: Freegrass on May 15, 2020, 08:18:30 PM
There's a whole lot going on in the Arctic right now...
That's probably why the man is looking so angry...
Title: Re: The 2020 melting season
Post by: oren on May 15, 2020, 08:21:56 PM
FG, this belongs in the Pareidolia thread, I would move it but I lack moderation authority there.
Title: Re: The 2020 melting season
Post by: Freegrass on May 15, 2020, 08:23:34 PM
FG, this belongs in the Pareidolia thread, I would move it but I lack moderation authority there.
I know Oren, but I thought it was suitable for the moment... It's an alternative smiley... ;)
Title: Re: The 2020 melting season
Post by: pearscot on May 15, 2020, 08:28:35 PM
True...I mean it is a Friday!

I also never noticed that 'grumpy man' before until now, but I definitely see it.

Whelp, given what I've seen already I do expect to see the Greenland mega crack to appear again. If I see more evidence/clear imagery I will post it in that thread.

I was reading the extended forecast for Barrow, and while it will stay below freezing, the high pressure over the central Arctic is expected to remain in place a while longer. What extent will this have with regards to pre-conditioning?? I don't know yet...
Title: Re: The 2020 melting season
Post by: Freegrass on May 15, 2020, 08:49:58 PM
True...I mean it is a Friday!

I also never noticed that 'grumpy man' before until now, but I definitely see it.
And now you can never unsee it again! (https://forum.arctic-sea-ice.net/proxy.php?request=http%3A%2F%2Fwww.mysmiley.net%2Fgoogle%2Fgoogle_face-with-tears-of-joy_9602_mysmiley.net.png&hash=2452b9b78c35d761984537f823a993d9)
Quote
Whelp, given what I've seen already I do expect to see the Greenland mega crack to appear again. If I see more evidence/clear imagery I will post it in that thread.
The reason for this "Ellesmere crack" is strong wind that's been blowing there for the last 2 days (https://earth.nullschool.net/#2020/05/14/1800Z/wind/surface/level/orthographic=-45.02,91.24,2304). (Link is to Nullschool). Probably combined with the rotation of the anticyclone that's putting pressure on the entire ice pack?

Happy Friday!
Title: Re: The 2020 melting season
Post by: pearscot on May 15, 2020, 09:10:14 PM
True...I mean it is a Friday!

I also never noticed that 'grumpy man' before until now, but I definitely see it.
And now you can never unsee it again! (https://forum.arctic-sea-ice.net/proxy.php?request=http%3A%2F%2Fwww.mysmiley.net%2Fgoogle%2Fgoogle_face-with-tears-of-joy_9602_mysmiley.net.png&hash=2452b9b78c35d761984537f823a993d9)
Quote
Whelp, given what I've seen already I do expect to see the Greenland mega crack to appear again. If I see more evidence/clear imagery I will post it in that thread.
The reason for this "Ellesmere crack" is strong wind that's been blowing there for the last 2 days (https://earth.nullschool.net/#2020/05/14/1800Z/wind/surface/level/orthographic=-45.02,91.24,2304). (Link is to Nullschool). Probably combined with the rotation of the anticyclone that's putting pressure on the entire ice pack?

Happy Friday!

Happy Friday indeed! I can't wait to have a drink after work today.

To your point - it looks like the overall wind pattern is blowing west across that new crack toward the north slope of Alaska. At the same time, the rather potent storm which was situated near Svalbard/Fram Strait is/was pulling at the pack either south or southeast.

Either way, it is quite substantial and near the wider points I measured between 12-14 miles across. I do often wonder how quickly an artifact like that begins to affect the surrounding ice.

I live on an island in the Puget Sound, and I can tell you that even in small, 5 mile areas of open water (which are normally calm) can produce some significant waves given the right winds. Additionally, the dark sea will begin to instantly soak up any solar energy.
Title: Re: The 2020 melting season
Post by: ArcticMelt2 on May 15, 2020, 10:44:17 PM
https://www.washingtonpost.com/weather/2020/05/15/arctic-heat-wave-breaks-records/

Quote
Heat spike elevates Arctic to warmest levels this early in the year since at least 1958

A heat wave of historic proportions is gripping the Central Arctic, with the region setting a milestone for being so warm relative to average so early in the year.

According to a regional climate database that goes back to 1958, this week’s temperature spike in the Arctic, as defined as the region north of 80 degrees latitude, is unprecedented during that time period.

According to Martin Stendel, a climate scientist at the Danish Meteorological Institute (DMI), the temperature data set, which is known as a reanalysis, shows how unusual the Arctic temperature anomalies are in the context of the past several decades.

“Concerning the Arctic temperature, that is indeed quite extraordinary. In the time series which is based on ERA40 and therefore goes back to 1958, there is no similar event so early in the season,” Stendel wrote in an email. “There is (again) very little sea ice in the Arctic (only 2019 had less),” Stendel noted.

A reanalysis is a way to put together a thorough record of how weather and climate conditions have varied over time.

The temperature spike, which is in part related to unusually mild air for this time of year flowing northward from the Russian Arctic, may have significant consequences. The milder temperatures and unusually clear skies could accelerate ice melt of sea and land ice across the vast region, particularly if cold snaps do not quickly follow.

Above-freezing temperatures are showing up in the Central Arctic about one month earlier than average this week, according to Ted Scambos, a senior research scientist at CIRES, an atmospheric research institute operated by the National Oceanic and Atmospheric Administration and the University of Colorado at Boulder.

Zack Labe, a graduate student at the University of California at Irvine who studies Arctic climate change, said he’s not convinced there is an early-season record for Arctic temperature departures from average because the reanalysis in use is older and less precise than more updated records.

“While it’s representative of warm or cold periods, I don’t think we can’t say much about ‘records’ from using it,” Labe said of the temperature reanalysis. “Regardless of records, this is definitely an unusually warm period across the entire Arctic Ocean. I think a weather pattern like this, but in June, would be particularly bad for sea ice.”

Computer model projections show mild temperature anomalies covering a vast expanse, stretching from the Barents and Kara seas near Siberia (which itself is unusually mild for this time of year) to the Chukchi Sea off the Alaskan coast.

These anomalous readings are reflected in the average temperature over the high Arctic (north of 80 degrees latitude), which has spiked in recent days, rising about 16 degrees (9C).

This unusually mild air mass is expected to stay in place for at least the next seven to 10 days, possibly longer, computer model projections show. A high-pressure area parked over the Central Arctic will also ensure clear skies, which is a key ingredient in warm season extreme melt events due to feedback loops involving melting snow and sea ice.

While sea ice melt tends to kick into gear in June, Scambos says the weather this week could cause the snowpack on top of the sea ice to “ripen” early in the season, which would cause the snow to get some liquid meltwater in it, lowering its reflectivity, or albedo, and absorbing more incoming solar energy. This would precondition the sea ice to more rapid and widespread melting earlier in the season, depending on the weather.
Title: Re: The 2020 melting season
Post by: pearscot on May 15, 2020, 11:09:44 PM
Thanks for posting that article, it makes sense and I agree with the conclusions on it. Compared to other years, I do not remember seeing everything be so clear...

Just a sign of the slowing jet stream when these large weather systems/patterns become stuck.
Title: Re: The 2020 melting season
Post by: Freegrass on May 15, 2020, 11:20:56 PM
Thanks for posting that article, it makes sense and I agree with the conclusions on it. Compared to other years, I do not remember seeing everything be so clear...

Just a sign of the slowing jet stream when these large weather systems/patterns become stuck.
A good article indeed! I just don't agree with your conclusion, that this is "a sign of the slowing jet stream". I think this is a clear sign of global dimming, that is now taken away, giving us the full impact of global warming. A slowing of the jet stream is a consequence, not a cause!
Title: Re: The 2020 melting season
Post by: ArcticMelt2 on May 15, 2020, 11:29:24 PM
Last year, on the Pacific side, ice broke much faster - it was a very warm winter. But now there is much less old ice.

http://www.aari.ru/resources/d0015/arctic/gif.en/2020/20200512.gif

http://www.aari.ru/resources/d0015/arctic/gif.en/2019/20190514.gif

http://www.aari.ru/resources/d0015/arctic/gif.en/2012/20120515.gif
Title: Re: The 2020 melting season
Post by: pearscot on May 15, 2020, 11:31:16 PM
Thanks for posting that article, it makes sense and I agree with the conclusions on it. Compared to other years, I do not remember seeing everything be so clear...

Just a sign of the slowing jet stream when these large weather systems/patterns become stuck.
A good article indeed! I just don't agree with your conclusion, that this is "a sign of the slowing jet stream". I think this is a clear sign of global dimming, that is now taken away, giving us the full impact of global warming. A slowing of the jet stream is a consequence, not a cause!

Oh, I meant that the conclusion makes sense insofar as an explanation to the regional clarity. I've noticed and commented on it, but I've only followed the ice closely since 2013, so what appears "new" to me has often been seen by others.

Anyways, I get your point and agree with that - I just didn't articulate what I wanted to well. I should have said: As a result of the warming arctic and less temperature differentiation between the equator and north pole, weather systems get 'stuck' as an implication of a slowed, wavy jet stream; what we are witnessing now is a result and negative feedback of the damage already imparted on the system at large.

The real question is (and I'm sure Frivolous would have some good insight), how much will this high pressure system precondition the ice later in the summer?
Title: Re: The 2020 melting season
Post by: Freegrass on May 16, 2020, 12:24:51 AM
Oh, I meant that the conclusion makes sense insofar as an explanation to the regional clarity. I've noticed and commented on it, but I've only followed the ice closely since 2013, so what appears "new" to me has often been seen by others.

Anyways, I get your point and agree with that - I just didn't articulate what I wanted to well. I should have said: As a result of the warming arctic and less temperature differentiation between the equator and north pole, weather systems get 'stuck' as an implication of a slowed, wavy jet stream; what we are witnessing now is a result and negative feedback of the damage already imparted on the system at large.
That took to much effort to think about on a Friday night...  ;D 

Quote
The real question is (and I'm sure Frivolous would have some good insight), how much will this high pressure system precondition the ice later in the summer?
I don't think the problem is the weather right now. I think the problem is that the weather will be like this all summer long...
Title: Re: The 2020 melting season
Post by: SteveMDFP on May 16, 2020, 12:37:52 AM
https://www.washingtonpost.com/weather/2020/05/15/arctic-heat-wave-breaks-records/

I was nearly gobsmacked to read such a clear, accurate and nuanced article in the mainstream press--about *any* technical subject, let alone the arctic.

Then I looked at the article, by Andrew Freedman, of the "Capital Weather Gang."  The group produces excellent meteorological and climatological reporting.   As I'm in that capital area, I've benefited from their expertise before.
Title: Re: The 2020 melting season
Post by: thejazzmarauder on May 16, 2020, 12:45:20 AM
...The real question is (and I'm sure Frivolous would have some good insight), how much will this high pressure system precondition the ice later in the summer?

That's what we're waiting to see. There's definitely going to be some significant extent drops over the next 7-10 days, but what matters more than anything else (re: extent/area minimum) is how much melt-ponding this system causes. We're (probably) fortunate this high pressure didn't hit 2-3 weeks later.
Title: Re: The 2020 melting season
Post by: RoxTheGeologist on May 16, 2020, 01:40:03 AM

...
Is this normal? ...

Perhaps the reduced aerosols are contributing to the reduced cloud cover more than would be expected.  I don't know much about the specifics there but maybe the relationship between aerosol density and cloud formation isn't linear or continuous.
I would think that besides the ~1/3 reduction in global aerosols (I could be grossly off o this # but I think it is reasonable), the 90% drop in air traffic is the biggest contributor to the lack of clouds. Or, the drop in air traffic at this point may be taking primacy even over the drop in aerosols. There was a study after 9/11 that showed a major rise in temperatures when air traffic halted. This is now being replicated much more severely across the entire planet.

Contrails are thought to have a net warming effect, particularly as they form more readily at night rather than day. Clouds keep the planet warm.

https://journals.ametsoc.org/doi/full/10.1175/JCLI-D-19-0467.1

" In contrast, the level of understanding for contrail cirrus impact has been thoroughly upgraded during the last 10 years, and it is currently considered as the largest component contributing to aircraft-induced radiative forcing (Burkhardt and Kärcher 2011; Schumann and Graf 2013; Bock and Burkhardt 2016b; Grewe et al. 2017)."
Title: Re: The 2020 melting season
Post by: Glen Koehler on May 16, 2020, 01:47:20 AM
    Ditto ArcticMelt2, thanks for the WAPost article and also those ice thickness images.  They could have spiced it up with some ASIF quotes from the Fabulous Friv.  It is a credit to the ASIF that the experts quoted in the article didn't add to what has already been noted in greater detail in the forum.  Good to see a major US press outlet paying attention to news that matters vs the latest ramblings of the mad King.  Actually, the WAPost climate team led by Chris Mooney is among the best of all the major newspapers/magazines.  Mooney even did a story about Neven and the ASIF back in 2016: https://www.washingtonpost.com/news/energy-environment/wp/2016/11/30/he-created-a-beloved-blog-about-the-melting-arctic-but-it-got-harder-and-harder-to-write/ (https://www.washingtonpost.com/news/energy-environment/wp/2016/11/30/he-created-a-beloved-blog-about-the-melting-arctic-but-it-got-harder-and-harder-to-write/)

     Comparing the 2012, 2019 & 2020 sea ice thickness images, the one strength 2020 had was the thick ice near the Fram Strait.  That is the very ice that was presumably pummeled by the warmth, sun, and WIND this week.   2012 and 2019 each had a long arm that may have impeded Arctic-wide rotation.  2020 lacks that structural brace.  I don't know if Arctic-wide ice translocation is affected by the distribution of thick ice at that scale.  The significance of that pattern could just be a visual figment of my imagination.  (Or as Pete Walker said: a "Fig Newton of my immaculation") 

     The last 7 days of the current GFS shows Kara Sea temps consistently above 0C.  Not much clear sky & direct sun in that forecast, but the clouds bring some rain (too warm for snow) to deliver additional thermal energy to the surface.  All of which leads to forecast zero snow cover in the Kara by May 24 https://climatereanalyzer.org/wx/fcst/#gfs.arc-lea.snowd-mslp (https://climatereanalyzer.org/wx/fcst/#gfs.arc-lea.snowd-mslp).

    The Kara is already running below previous years (https://forum.arctic-sea-ice.net/index.php/topic,2975.600.html#lastPost (https://forum.arctic-sea-ice.net/index.php/topic,2975.600.html#lastPost) thanks to Gerontocrat).  Putting that together with the forecast suggests that by June 1 the Kara could be in unprecedented condition.

    The Barents Sea hardly seems to matter since any ice in it is doomed anyway.  But FWIW, Earth Nullschool shows continued low-pressure system winds scouring it out for another day or two.  Does it make much difference to clear the lanes for more export out of the CAB?  Erosion of the ice on the CAB - Barents border can't help.  At least the great Fram Flush of early 2020 has ended. 

     Following up on Freegrass's tiptoe through the tulips of DMI images, looking at the DMI temperature graph for every year since 1958 shows that this early-mid May warmup has no real match in previous years. 

     It seems like every year the ASIF gets all heated about impending ice doom.  2020 so far is providing some hard numbers in that direction.  Yes, it is still early, but as wiser watchers have noted, it is the early momentum that sets the stage for the rest of the melt season.  True enough that a basin-scale clear-sky event would be worse if it happened 2-3 weeks from now and closer to the solar max.  Then again, decreasing albedo well BEFORE the solar max increases the impact of reduced reflection of solar radiation. And having a clear-sky event early does not preclude having another one later.
Title: Re: The 2020 melting season
Post by: Paul on May 16, 2020, 02:46:17 AM
...The real question is (and I'm sure Frivolous would have some good insight), how much will this high pressure system precondition the ice later in the summer?

That's what we're waiting to see. There's definitely going to be some significant extent drops over the next 7-10 days, but what matters more than anything else (re: extent/area minimum) is how much melt-ponding this system causes. We're (probably) fortunate this high pressure didn't hit 2-3 weeks later.

Unless your psychic then nothing is a definate, especially in the Arctic in anycase. I would not be surprised if we see quite large extent drops because alot of ice in the Barants sea has melted/compacted/exported and melting is occurring in other regions such as the Kara Sea and Baffin Bay and both regions are quite low at the moment.

On the most part, weather conditions will turn alot slacker and pressure will fall in parts of the basin, basically weather conditions that should mean good news for sea ice.

The main exception to the rule will be the Kara sea, really unusually warm conditions hitting here at times and it's all ready hitting the snow cover there and will continue to do so.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 16, 2020, 04:33:19 AM
Of course it's not reliable, but GFS supposes  Eurasia will lost much of its remaining snow by May 25. Also huge areas of the Beaufort, Chuckchi, ESS, Laptev sea ice will also lose snow what mean ice turning blue

That's crazy.  The mosaic team instruments show less than 10 cm of snow around their boat.

Yet that forecast goes 30 to 40 cm in like 2 weeks that's crazy
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 16, 2020, 04:34:42 AM
No they're being a mega high pressure ridge is not normal that it's unprecedented for this time of year.

Also aerosols are not the reason it's clear
Title: Re: The 2020 melting season
Post by: binntho on May 16, 2020, 07:05:03 AM
Contrails are thought to have a net warming effect, particularly as they form more readily at night rather than day. Clouds keep the planet warm.

I'm not surprised that this would be the global or average effects of contrails. But specifically in the Arctic summer months, where "night" is a dodgy subject? I'm not so sure.

As for aerosols in general, apparently the Arctic wildfires from last season have been smouldering under the snow all winter and are now reappearing in unusually large numbers. Arctic peat fires must be the biggest source of aerosols over the Arctic in a normal year? Does anyone know?

See this New Scientist article about Zombie Fires (https://www.newscientist.com/article/2243591-zombie-fires-are-burning-the-arctic-after-smouldering-under-snow/)

As regards the general cloudiness of the Arctic, my feeling would be that those clouds that reach the arctic are mostly formed elsewhere, predominantly in the mid-latitudes, and given the sharp drop in aerosol pollution there, a drop in cloudiness over the Arctic would follow a general drop in cloudiness in lower latitudes - but has anybody got any idea if that is the case or not?
Title: Re: The 2020 melting season
Post by: wdmn on May 16, 2020, 07:19:55 AM
I don't think that this season will count as sufficient proof for anything. The systems are too complex. But what needs to be explained is clear: record early warmth (temperature wise) in the arctic, and unprecedented (in the record) early-mid-may sunshine over the arctic. Is this the result of long term degradation of the polar cell? Decline in flights over the arctic? Drops in aerosol emissions?

What would be the criteria for distinguishing the cause(s)?

What we do know is that the arctic is being primed enough that if weather is favourable we will see a record year for ice extent. But that is true every year.

In humility we can say that the arctic sea ice is in trouble and we are in a new age of disruption where we will have to rely on resilience to get civilization through. The only prudent thing is to act as though we have no time to make our systems more resilient and more stable as we enter a time of instability and disruption. Are we at all capable of response?
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 16, 2020, 08:07:36 AM
The surface albedo over 2/3rds of the Arctic basin from the Eurasian side though the central Arctic basin maybe even touching the CAB.


This is super remarkable.

The models however after day 5-6 show benign cloudy cooler conditions with the warmth mostly confined to the Kara, laptev, and Atlantic side.

The models show the Beaufort region getting skirted by warm air some.

We'll see how it all plays out.

What is most important is whether the surface will freeze back up and cause the albedo rise.

Even under cloudy conditions lower albedo will definitely cause surface warming more with Lower albedo.

You can see in the two images I posted that the albedo change has been extraordinary.

For anytime of year.

We now know even in middle May.  Well really early half of middle May the artic basin.

Amazing

Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 16, 2020, 08:37:25 AM
Guys the anomalous ridging is a huge energy transferring event.

Aeresols being reduced cannot possibly be a catalyst in the atmospheric process that causes such anomalous events over such a large area.

It's not just 2D coverage.

It's the 4D/3D plane in which the energy tranfer, wind mixing, moisture density, air density, surface changes.. All of that goes into this process.

Not just the large ridge that  has been stacked all the way to to 300mb to the surface but also the vortex pieces that move around the ridging.

These pieces cover much more area than the ridging(55-70N). This is where huge amounts of heat/moisture are transferred.

Just saying that's my arm chair analysis.

Either way its tremendous!!!
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 16, 2020, 09:13:34 AM
The 00Z euro is out and model trends in the medium range are quite variable.  Which makes sense considering the huge change in lower tropospheric energy right now.

Anyways a couple notes...

1. The Kara region, including the laptev and Atlantic region are in line for a big blast of WAA and sun day 5 plus.

The models have continued to enhance this.

But more importantly....

2.

The euro is now showing what would likely be record warmth through Alaska and the Yukon that spills into the Western CAB and Beaufort, eventually the Chuchki...

That unfolds after day 6.

But then day 7-10 another ridge is developing over the Pacific side of the Arctic basin.

Very very interesting May
Title: Re: The 2020 melting season
Post by: jdallen on May 16, 2020, 10:05:16 AM
...The real question is (and I'm sure Frivolous would have some good insight), how much will this high pressure system precondition the ice later in the summer?

That's what we're waiting to see. There's definitely going to be some significant extent drops over the next 7-10 days, but what matters more than anything else (re: extent/area minimum) is how much melt-ponding this system causes. We're (probably) fortunate this high pressure didn't hit 2-3 weeks later.

Watch this map.

https://climatereanalyzer.org/wx/fcst/#gfs.arc-lea.snowd-mslp

... and we actually are not fortunate this is hitting early.  In fact in ways, I think it is worse.  All that disappearing snow on the pack is turning into sub-surface or surface melt ponds.

What's happening right now is we've extended the melt season about 4 weeks, from early June into early May.

Hunch:  The 30cm line on May 20th may be a harbinger of our end of season extent this year.

This presumes we don't have weather in mid season that blows things out even worse than they are rocketing towards currently.

(Edit:  Note that in the next 5 days the model shows pretty much all the remaining land snow cover on the Eurasian side of the Arctic getting massacred.  Things are going to get hot, early.)
Title: Re: The 2020 melting season
Post by: jdallen on May 16, 2020, 10:30:36 AM
The surface albedo over 2/3rds of the Arctic basin from the Eurasian side though the central Arctic basin maybe even touching the CAB.
<snip>
The models however after day 5-6 show benign cloudy cooler conditions with the warmth mostly confined to the Kara, laptev, and Atlantic side.
<snip>
You can see in the two images I posted that the albedo change has been extraordinary.
<snip>
We now know even in middle May.  Well really early half of middle May the artic basin.

Amazing

Even with improving conditions in another week, I don't  think the albedo on the peripheral seas is going to recover.  With the warming projected around the same time on the Beaufort/Chukchi side, those seas will likely join the others.  Any remaining ice in the Bering and Okhotsk will be erased, catching 2020 up with the events of the last 3 years in the Bering.

I am very concerned with these early enormous increases in the Arctic's heat budget.
Title: Re: The 2020 melting season
Post by: Aluminium on May 16, 2020, 11:13:46 AM
May 11-15.

2019 (https://forum.arctic-sea-ice.net/index.php/topic,2591.msg199491.html#msg199491).
Title: Re: The 2020 melting season
Post by: gerontocrat on May 16, 2020, 11:26:07 AM
That's quite a big hole appearing North & West of Svalbard - the first significant damage to ice North of 80.
Title: Re: The 2020 melting season
Post by: bluice on May 16, 2020, 11:35:37 AM
Interesting to see where the massive extent loss takes place. Widespread ice loss on the Eurasian side, all the say from Svalbard to north west corner of Alaska.

Ice between Svalbard and FJL will be gone shortly.
Title: Re: The 2020 melting season
Post by: blumenkraft on May 16, 2020, 12:54:10 PM
It rained north of Svalbard.
Title: Re: The 2020 melting season
Post by: binntho on May 16, 2020, 01:59:26 PM
May 11-15.

2019 (https://forum.arctic-sea-ice.net/index.php/topic,2591.msg199491.html#msg199491).

That really looks scary, and even more so after comparing it to 2019. We have seen Atlantification of the Barents, now we are seeing Swisscheesification of the entire Arctic ...
Title: Re: The 2020 melting season
Post by: blumenkraft on May 16, 2020, 02:04:45 PM
"Swisscheesification" << That's such a great word creation, Binntho. Kudos to you!
Title: Re: The 2020 melting season
Post by: Glen Koehler on May 16, 2020, 02:56:49 PM
<snip>  "now we are seeing Swisscheesification of the entire Arctic ..."

      Question 1:  Do those dark areas really indicate low concentration ice or does the sensor get fooled by moisture in the air column between surface and satellite?  I am not proposing, just asking.  Others have suggested that is the case.  If so, note that at the far end of the 10-day GFS there is an incursion of moist air over the central CAB https://climatereanalyzer.org/wx/fcst/#gfs.arc-lea.pwtr (https://climatereanalyzer.org/wx/fcst/#gfs.arc-lea.pwtr).  I was told by a climate scientist last year that such incursions were unusual, and that they contribute to localized warming, but take that as a second-hand anecdote from a less than perfect memory.

--------------------------
<snip> Watch this map.
https://climatereanalyzer.org/wx/fcst/#gfs.arc-lea.snowd-mslp

... and we actually are not fortunate this is hitting early.  In fact in ways, I think it is worse.  All that disappearing snow on the pack is turning into sub-surface or surface melt ponds.

What's happening right now is we've extended the melt season about 4 weeks, from early June into early May.

Hunch:  The 30cm line on May 20th may be a harbinger of our end of season extent this year.

     Question 2:  That is an interesting concept for a long-range predictor for September sea ice Extent.  Is there historical analysis supporting that or something like it? 

     Which raises Question 3:  In addition to waiting for each new GFS or EURO model run, are there any publically available multi-week or seasonal weather forecasts for the Arctic basin with useful skill?  NOAA produces seasonal temp. and precip forecasts for the US that have useful skill out to several months for temp., and out to several weeks - 1 month for precip.  These are not weather forecasts for what will happen on this or that day, but trends for the period as a whole.  Having a skillful multi-week temperature or pressure forecast for the Arctic basin would be very interesting.

------------------------

     GFS vs. EURO  The differences between GFS and EURO are not that great, that's not me talking, it's Marshall Sheperd former president of American Met. Society, and him quoting the director of the EURO model.
https://www.forbes.com/sites/marshallshepherd/2019/02/14/euro-vs-gfs-weather-model-wars-take-a-new-turn-in-march/#7c3625286c2b (https://www.forbes.com/sites/marshallshepherd/2019/02/14/euro-vs-gfs-weather-model-wars-take-a-new-turn-in-march/#7c3625286c2b)

       Look at the forecast correlation stats and you see that the EURO does do better overall, but that is not always the case, and in general the scores are within a few percentage points.  GFS is pretty darned good so let's stop insulting it and by doing so dragging on the people who provide it.  And there is considerable investment in new computers, data systems, modeling physics, human and other resources underway that bodes well for continued progress with the FV3-GFS platform that went online last June. 

     Of course, the EURO is not standing still either.  Shepherd points out that the different met centers from around the world work closely together to help each other.  That's the kind of cooperative competition we need to pull out of our global tailspin. 

      The number of satellite, doppler radar, and other technological developments in the past decade is amazing.  If you need some good news, check out the COSMIC program.https://www.youtube.com/watch?v=VU7kJA1FNQQ (https://www.youtube.com/watch?v=VU7kJA1FNQQ)
  It seems that the original COSMIC  readings include the Arctic.  Great to see a much-improved COSMIC-2 for the lower latitudes.  Now we need a COSMIC-3 covering the polar regions.  (Outside my wheelhouse, but I think that is possible)  It's a matter of priorities not resources.  Understanding and preserving a climate that supports human civilization should be a top priority.  Pay for knowledge now or pay for damages later.

Title: Re: The 2020 melting season
Post by: blumenkraft on May 16, 2020, 03:25:09 PM
... or does the sensor get fooled by moisture in the air column between surface and satellite? ...

Glen, i bet that is the case for many of those patches. Check my 'rain north of Svalbard' posting above, and compare it with Aluminiums GIF (last frame) and it becomes pretty apparent IMHO.
Title: Re: The 2020 melting season
Post by: gerontocrat on May 16, 2020, 04:16:38 PM

Well, NSIDC says there is a big hole north of Svalbard. FJL (whoops)
And the Port of Longyearbyen shows a lot of open water & mucho bare patches on the land.

https://www.webcamgalore.com/webcam/Norway/Longyearbyen-Spitsbergen/1457.html

& the UK metoffice says what a lovely sunny day in Longyearbyen.
Title: Re: The 2020 melting season
Post by: Jim Hunt on May 16, 2020, 04:45:08 PM
Open water in the Laptev Sea emerging from under the clouds today:

https://GreatWhiteCon.info/resources/arctic-sea-ice-images/summer-2020-images/#Laptev
Title: Re: The 2020 melting season
Post by: Glen Koehler on May 16, 2020, 05:06:53 PM
<snip> That's quite a big hole appearing North & West of Svalbard - the first significant damage to ice North of 80.
    And some of that area had large positive ice thickness anomalies before the May 10-13 winds pushing out through the Fram Strait. 

    NSIDC vs. AMSR2 image shading:   The NSIDC shows low concentration at some of the same areas as AMSR2, but the light gray shading for the AMSR2 affects many more areas in addition.  The impression of widespread ice damage across much of the CAB in the AMSR2 image is not replicated in the NSIDC image.  That may be due to differences between NSIDC and AMRSR2 in choice of color thresholds for graphing.  Or maybe NSIDC has a way to filter out misleading signals due to atmospheric moisture. 

     My tentative conclusion is that the very dark areas fringing open water in the B&W AMSR2 image are representing low ice concentration, but that the wispy grayish areas over much of the CAB could be due to high air moisture.  And that the NSIDC graphic is more restricted to showing sea ice concentration.  The Kara Sea already looks pretty beat up in both of them.
Title: Re: The 2020 melting season
Post by: thejazzmarauder on May 16, 2020, 06:01:40 PM
...The real question is (and I'm sure Frivolous would have some good insight), how much will this high pressure system precondition the ice later in the summer?

That's what we're waiting to see. There's definitely going to be some significant extent drops over the next 7-10 days, but what matters more than anything else (re: extent/area minimum) is how much melt-ponding this system causes. We're (probably) fortunate this high pressure didn't hit 2-3 weeks later.

Watch this map.

https://climatereanalyzer.org/wx/fcst/#gfs.arc-lea.snowd-mslp

... and we actually are not fortunate this is hitting early.  In fact in ways, I think it is worse.  All that disappearing snow on the pack is turning into sub-surface or surface melt ponds.

What's happening right now is we've extended the melt season about 4 weeks, from early June into early May.

Hunch:  The 30cm line on May 20th may be a harbinger of our end of season extent this year.

This presumes we don't have weather in mid season that blows things out even worse than they are rocketing towards currently.

(Edit:  Note that in the next 5 days the model shows pretty much all the remaining land snow cover on the Eurasian side of the Arctic getting massacred.  Things are going to get hot, early.)

Would be interesting to see when land snow on Eurasian side has melted in years past.
Title: Re: The 2020 melting season
Post by: ArcticMelt2 on May 16, 2020, 06:50:41 PM
    Ditto ArcticMelt2, thanks for the WAPost article and also those ice thickness images.  They could have spiced it up with some ASIF quotes from the Fabulous Friv.  I think it is a credit to the ASIF that the experts quoted in the article didn't add to what has already been noted in greater detail in the forum.  Good to see a major US press outlet paying attention to news that matters vs the latest ramblings of the mad King.  Actually, the WAPost climate team led by Chris Mooney is among the best of all the major newspapers/magazines.  Mooney even did a story about Neven and the ASIF back in 2016: https://www.washingtonpost.com/news/energy-environment/wp/2016/11/30/he-created-a-beloved-blog-about-the-melting-arctic-but-it-got-harder-and-harder-to-write/ (https://www.washingtonpost.com/news/energy-environment/wp/2016/11/30/he-created-a-beloved-blog-about-the-melting-arctic-but-it-got-harder-and-harder-to-write/)

     Comparing the 2012, 2019 & 2020 sea ice thickness images, the one strength 2020 had was the thick ice near the Fram Strait.  That is the very ice that was presumably pummeled by the warmth, sun, and WIND this week.   2012 and 2019 each had a long arm that may have impeded Arctic-wide rotation.  2020 lacks that structural brace.  I don't know if Arctic-wide ice translocation is affected by the distribution of thick ice at that scale.  The significance of that pattern could just be a visual figment of my imagination.  (Or as Pete Walker said: a "Fig Newton of my immaculation") 

It is also noticeable on these maps that this year there is much less landfast ice in Siberia. Is this evidence of stronger warm winds in winter? In 2019, warm winds were mostly in the Alaska area.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 16, 2020, 09:21:56 PM
The surface albedo over 2/3rds of the Arctic basin from the Eurasian side though the central Arctic basin maybe even touching the CAB.
<snip>
The models however after day 5-6 show benign cloudy cooler conditions with the warmth mostly confined to the Kara, laptev, and Atlantic side.
<snip>
You can see in the two images I posted that the albedo change has been extraordinary.
<snip>
We now know even in middle May.  Well really early half of middle May the artic basin.

Amazing

Even with improving conditions in another week, I don't  think the albedo on the peripheral seas is going to recover.  With the warming projected around the same time on the Beaufort/Chukchi side, those seas will likely join the others.  Any remaining ice in the Bering and Okhotsk will be erased, catching 2020 up with the events of the last 3 years in the Bering.

I am very concerned with these early enormous increases in the Arctic's heat budget.

The 12Z euro after hour 120 slowly blows up a quasi-dipole with a huge blow torch over the Kara region as well.

But what it shows coming from the NA side is of most interest.

Just an amazing start to this melt season
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 16, 2020, 09:28:45 PM
...The real question is (and I'm sure Frivolous would have some good insight), how much will this high pressure system precondition the ice later in the summer?

That's what we're waiting to see. There's definitely going to be some significant extent drops over the next 7-10 days, but what matters more than anything else (re: extent/area minimum) is how much melt-ponding this system causes. We're (probably) fortunate this high pressure didn't hit 2-3 weeks later.

Watch this map.

https://climatereanalyzer.org/wx/fcst/#gfs.arc-lea.snowd-mslp

... and we actually are not fortunate this is hitting early.  In fact in ways, I think it is worse.  All that disappearing snow on the pack is turning into sub-surface or surface melt ponds.

What's happening right now is we've extended the melt season about 4 weeks, from early June into early May.

Hunch:  The 30cm line on May 20th may be a harbinger of our end of season extent this year.

This presumes we don't have weather in mid season that blows things out even worse than they are rocketing towards currently.

(Edit:  Note that in the next 5 days the model shows pretty much all the remaining land snow cover on the Eurasian side of the Arctic getting massacred.  Things are going to get hot, early.)

Would be interesting to see when land snow on Eurasian side has melted in years past.

Snow melt the last 15 years has accelerated versus before that.

However in the last 6-7 years the progressive loss of snow cover in May has slowed because snow depth/snow water equivalent has gone up.

A breakthrough is likely between 2020 and 2030.

But the more snow depth increases it will help slow the melt pace.


https://climate.rutgers.edu/snowcover/
Title: Re: The 2020 melting season
Post by: F.Tnioli on May 16, 2020, 09:44:22 PM

...
Is this normal? ...

Perhaps the reduced aerosols are contributing to the reduced cloud cover more than would be expected.  I don't know much about the specifics there but maybe the relationship between aerosol density and cloud formation isn't linear or continuous.
Alright you bozos, i'm sorta back. Must comment on this one!

There is no "perhaps" about it - it's a certainty. Most collegues do not expect the effect as they are not well familiar with papers akin to one i linked in this topic few pages above - about how aerosols affect athmosphere, and clouds in particular. One with plenty links to other ones, i mean.

Long story short, the "big" thing in the room about aerosols-affecting-clouds - is simple: the more microscopic solid particles inside clouds - the more condensation locations are available; so, same amount of water vapour which particular cloud contains - ends up condensating into more droplets (than without aerosols present). More droplets from same amount of vapour means smaller droplets. Smaller droplets means less precipitation occurs = i.e., more of the cloud remains in the air.

Of course, many other things also happen, but i'm quite sure the above mechanism is much more powerful than all other processes caused by reduction in aerosols.

As my remark above in the topic mentions, instruments confirm Arctic-wide overall aerosol reduction. It's so significant it can easily be eye-balled by comparing things like SO4 levels across CAB for same dates of this and previous years.

So - yes, sure, we have, and we will continue to have during this melting season, way less clouds - overall - than normal, unless something exceptionally strong would bring in much more water vapour into the Arctic than during previous years, of course. But then again, that would probably mean helluva lot extra heat coming in as well. Which, combined - heat and water vapour - would mean GACs going through, which summer-time spells doom for the ice no less than sunny skies.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 16, 2020, 09:51:50 PM
As someone said above the euro and GFS are currently in remarkable agreement through day 10.

Title: Re: The 2020 melting season
Post by: uniquorn on May 16, 2020, 10:05:05 PM
But what it shows coming from the NA side is of most interest.
Just an amazing start to this melt season
Friv, please divulge what is coming from the NA side. Atmo is not my strong point
Title: Re: The 2020 melting season
Post by: bbr2315 on May 16, 2020, 10:06:24 PM
But what it shows coming from the NA side is of most interest.
Just an amazing start to this melt season
Friv, please divulge what is coming from the NA side. Atmo is not my strong point
The hammer is being dropped on snowcover. It looks like there is also a lot of warmth in the NW of the continent, but this could be curtains for the remaining extant snow extent over Quebec / Nunavut. When that goes, there is going to be no barrier between continental airmasses and the CAA / Greenland, besides the ice in Hudson Bay, which is now losing albedo fairly quickly.
Title: Re: The 2020 melting season
Post by: Aluminium on May 16, 2020, 10:31:05 PM
10°C at 850 hPa is forecasted in the Kara Sea in 4 days. Somewhere with rain, somewhere with clear sky.
Title: Re: The 2020 melting season
Post by: uniquorn on May 16, 2020, 10:50:19 PM
wipneus regional extent and area (https://sites.google.com/site/arcticseaicegraphs/regional), kara, may15
edit: thanks bbr, and welcome back
Title: Re: The 2020 melting season
Post by: be cause on May 17, 2020, 12:37:37 AM
Kara earning a place in the peripheral seas ? I always keep an eye on Kara as early losses here usually portend a serious melting season . Last year was a rare exception ; we are now a month ahead of 2019 , when there was a major stall , something that looks unlikely this year . .
 Even after the comparatively cold winter , I too feel the ice is in serious trouble . While gfs and ecmwf are in near agreement to day 10 that the basin remains abnormally warm , gfs run to day 16 is even worse for the ice . Only the Lincoln sea looks safe from any melt before June .
  From 3 days out temps below -4'C are sparse and with a Beaufort high encouraging the gyre and lows on the Eurasian side resulting in a dipole there should be more movement as well as melt . b.c.
 
 
Title: Re: The 2020 melting season
Post by: bbr2315 on May 17, 2020, 01:07:45 AM
Kara earning a place in the peripheral seas ? I always keep an eye on Kara as early losses here usually portend a serious melting season . Last year was a rare exception ; we are now a month ahead of 2019 , when there was a major stall , something that looks unlikely this year . .
 Even after the comparatively cold winter , I too feel the ice is in serious trouble . While gfs and ecmwf are in near agreement to day 10 that the basin remains abnormally warm , gfs run to day 16 is even worse for the ice . Only the Lincoln sea looks safe from any melt before June .
  From 3 days out temps below -4'C are sparse and with a Beaufort high encouraging the gyre and lows on the Eurasian side resulting in a dipole there should be more movement as well as melt . b.c.
 
 

Those Kara graphs are pretty crazy, and if the 12z guidance is to be believed, we are only getting started / melt is going to become much more rapid in the next week or so.
Title: Re: The 2020 melting season
Post by: binntho on May 17, 2020, 04:21:41 AM
<snip>  "now we are seeing Swisscheesification of the entire Arctic ..."

      Question 1:  Do those dark areas really indicate low concentration ice or does the sensor get fooled by moisture in the air column between surface and satellite? 

The "swiss cheese" is famous for it's holes, not for any "dark areas". So my comment was only regarding the holes popping up in the ice all around the perifery, much more so than usual at this time of year, as per my feeble and increasingly decrepit memory. And definitely significantly more than 2019 as can be readily seen.

The "dark areas" are of course also much more prominent than usual, or so we seem to think, but I think I've learned the lesson some time ago not to take those too literally. Althogh one does wonder if some sort of Bluecheesefication is underway as well?
Title: Re: The 2020 melting season
Post by: binntho on May 17, 2020, 04:31:52 AM
Long story short, the "big" thing in the room about aerosols-affecting-clouds - is simple: the more microscopic solid particles inside clouds - the more condensation locations are available; so, same amount of water vapour which particular cloud contains - ends up condensating into more droplets (than without aerosols present). More droplets from same amount of vapour means smaller droplets. Smaller droplets means less precipitation occurs = i.e., more of the cloud remains in the air.

Thanks for this reminder. The evidence for a significant reduction in cloud cover due to the current sharp fall in aerosol pollution is getting stronger.

I mentioned earlier that I belive that most of the cloud cover that ends up in the Arctic actually originates in the mid-latitudes, coinciding with the areas seeing the biggest fall in aerosols.

But is anybody actually seeing this effect - is there less cloud cover now than usual in the mid-latitudes? Or in the Northern Hemisphere?
Title: Re: The 2020 melting season
Post by: RikW on May 17, 2020, 06:54:37 AM
The last 2 Monti’s felt very sunny in the Netherlands and it also entered the recordbooks as most sunny april since we started measuring it.

And at the ‘higher’ areas drought is getting a real probleem; farmers who aren’t allowed to use water for their crops

And last weeks of march and first weeks of march are the same



Just checked some statistics, we had 560 sunhours since march 15th, former record was 503, which was in 2011; and only  23mm of rain
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 17, 2020, 08:07:51 AM
Both the 00z GFS and GEM are in lockstep still for the current ridge of high pressure to keep sliding into Siberia and fade away.


Then day 4-5 the Kara gets completely smoked with WAA. But models have backed off a bit on the extent (NO PUN INTENDED) of how far into the basin the slug of abnormally flame thrower level heat that gets two pump chump thumped & bumped into the main pack of floating ice on sea water.

However after hour 120 a ridge that's elongated in an ovalish N/S way develops over NWNA up through the Western Canadian Basin.

This is a slow developer but none the less scours out the cold air over the Western CAB.

By this point the snow pack West of the CAA will be essentially gone.

So the warm Southerly flow will aid whatever sun breaks out and decimate the  ice surface albedo in said region.

In other news check out the amazing SNOW COVER CHANGE IN NE SIBERIA.

Click to animate
Title: Re: The 2020 melting season
Post by: El Cid on May 17, 2020, 08:19:02 AM
I mentioned earlier that I belive that most of the cloud cover that ends up in the Arctic actually originates in the mid-latitudes, coinciding with the areas seeing the biggest fall in aerosols.

But is anybody actually seeing this effect - is there less cloud cover now than usual in the mid-latitudes? Or in the Northern Hemisphere?

Hardly any rain here (20 mm in 2 months, while average is 120 mm for 2 months) as well and lots of sunshine in March-April-May (basically since the lockdowns started). No proof of the lockdown-aerosol reduction effects, but I think there could be something to it. I have never seen so far, so clearly from our montaintop, I could see other mountains 2-300 kms away. Air was very clear and cloudless during the lockdowns. This is of course only anecdotal evidence but still...
Title: Re: The 2020 melting season
Post by: ArcticMelt2 on May 17, 2020, 08:30:19 AM
wipneus regional extent and area (https://sites.google.com/site/arcticseaicegraphs/regional), kara, may15
edit: thanks bbr, and welcome back

No wonder.
Title: Re: The 2020 melting season
Post by: F.Tnioli on May 17, 2020, 11:34:34 AM
Hardly any rain here (20 mm in 2 months, while average is 120 mm for 2 months) as well and lots of sunshine in March-April-May (basically since the lockdowns started). No proof of the lockdown-aerosol reduction effects, but I think there could be something to it. I have never seen so far, so clearly from our montaintop, I could see other mountains 2-300 kms away. Air was very clear and cloudless during the lockdowns. This is of course only anecdotal evidence but still...
Thanks for sharing it. From such small bits, bigger picture forms.

And it's not anecdotal. "Anecdotal" means: "evidence collected in a casual or informal manner and relying heavily or entirely on personal testimony". What you just said does not qualify to be "anecdotal", because it was not collected in "casual or informal manner" as relevant to the essense of your testimony. There is nothing "casual" nor "informal" about reporting specific range for visibility at a specific location, which you did; nor about specific amount of precipitation (20mm) as compared to usual average (120mm) for specific length of time (2 months).

Similar thing happens where i am at this time, too. I've never seen such a bright blue sky here during some 20+ years i am regularly present in the area. Now i see it almost every day, as even rainy days here - now often happen without complete (full) cloud cover during the day, instead being partially cloudy days (of which we had 20 out of 30 days of April here, which is above average for the month).

P.S. Plenty sun, too (now this is anecdotal alright) - bothers me personally as my main PC is right next to a SW window. Means i gotta bump up brightness / contrast of my display during those evening-sunshine hours, and then i gotta drop 'em down to low once sun sets. Problem is, sometimes i forget, and then it strains me eyes. Can i lawsuit 'em ones responsible for the whole pandemic / lockdown / clearer skies situation for extra bits of that eye damage i get as a result? Yeah. Figures. :D
Title: Re: The 2020 melting season
Post by: blumenkraft on May 17, 2020, 08:21:05 PM
Sunday movies starts with the 7-day hindsight mean temperature anomalies.

Attached the DMI 80°N 2m Temperatures.
Title: Re: The 2020 melting season
Post by: blumenkraft on May 17, 2020, 08:22:27 PM
Fram export via SAR.

Click to play.
Title: Re: The 2020 melting season
Post by: blumenkraft on May 17, 2020, 08:24:01 PM
Ice drift map. We have the whole ice pack rotating clockwise.
Title: Re: The 2020 melting season
Post by: pearscot on May 17, 2020, 08:43:55 PM
Interesting to see that rotation. It certainly helps to explain why the Fram Strait is currently so full of ice being flushed out. I've also seen more of those substantial cracks appearing on Beaufort Sea's coast. It's been so cloudy over Greenland that it's hard to tell what has happened over the last week.

Either way, the insane amount of direct sun over the East Siberian/Laptev Seas will certainly allow to ice to more freely rotate. I suppose I find this telling given how the central ice pack seemed to sheer away from the entire Queen Elizabeth Islands area last year. What a wild start to the year!
Title: Re: The 2020 melting season
Post by: Aluminium on May 17, 2020, 09:54:30 PM
Intense hot attacks from Siberia next 10 days. Note: the warmest time in Siberia is 3-6 hours earlier.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 17, 2020, 10:26:23 PM
The models still bring a quasi-dipole post day 7.

But have pushed back the arrival of the development of the ridge a couple days.

Even then the WAA is dependent On the development of a decently strong vortex.



The issue which has been the same issue since 2013 is the large +AO/+NAO that blows up centered on GIS and the Eastern CAA/NE mainland Canada.


It is more and more apparent that 05, 07-12 was highly HIGHLY ANOMALOUS.

now granted this only goes out to May 27th.

It's still disappointing.  People can argue why do I want to see arctic death.

Well it's inevitable and exciting
Title: Re: The 2020 melting season
Post by: The Walrus on May 17, 2020, 10:52:03 PM
wipneus regional extent and area (https://sites.google.com/site/arcticseaicegraphs/regional), kara, may15
edit: thanks bbr, and welcome back

No wonder.

Wow!  That graph should little, if any, temperature anomaly between 60N and 60S, but significant increases above and below.  Polar amplification anyone?
Title: Re: The 2020 melting season
Post by: Glen Koehler on May 18, 2020, 02:55:53 AM
RE AMSR2 image:
The "dark areas" are of course also much more prominent than usual, or so we seem to think, but I think I've learned the lesson some time ago not to take those too literally. Althogh one does wonder if some sort of Bluecheesefication is underway as well?

    There may be something to "Bluecheeseification".  If the wispy gray-dark areas over the CAB in the AMSR2 image are in fact indicating high moisture content in the air, that does not necessarily make it disconnected from the ice condition.  Because where did that moisture come from? 

    My first guess was that it's just part of the weather system, some air masses more moisture than others.  If so, then the air moisture would be a misleading signal not connected to the condition of the ice.  But now I'm wondering if perhaps those darj areas are showing higher air moisture caused by surface melt or lower concentration ice with more openings to allow communication of CAB water to the air above it.  Total speculation of course.  But it fits with the Bluecheeseification idea.
   
Title: Re: The 2020 melting season
Post by: Glen Koehler on May 18, 2020, 03:15:03 AM
Ice drift map. We have the whole ice pack rotating clockwise.
     Recent paper by Walt Meier et al found 10% per decade increase in ASI motion.  The May 8-16 ice drift map seems like it will contribute to that trend, though I don't have any info on what the average ice drift at this time of year looks like.  There are some long arrows in that image. 

    The recent high winds pretty well cleaned out the ice that was around Svalbard and FJL.  When the 2020 melt season story is written that seems like a major event to include.  Not as dramatic as the GAC of 2012, but the ice that was removed was one the remaining reservoirs of relatively thick ice.

    A highly mobile pack would be a major contributing factor for a wipeout melt season.  Too early to know season-long prospects of course.   The Arctic wide GFS forecast does not look as bad for the ice as last week.  The Kara is still in for some heat, and Mid-May has been one heck of a start. 
Title: Re: The 2020 melting season
Post by: GoSouthYoungins on May 18, 2020, 05:04:02 AM
The ice is thin and weak. Thus mobile. EVERYWHERE.

So the ice drifts with the polar easterlies and every western coast is bare earlier practically every year.

But next year I think it will all recover  ;)
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 18, 2020, 05:40:33 AM
According to multiple buoys temps in the Southern Beaufort have gone above freezing the last few days.

While temps over the Western CAB havent but have come close.

This will take 2 posts to upload 6 images.

Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 18, 2020, 05:49:26 AM
The two ITPs above show the temps further West/North however you want to look at it going above freezing.

The one I'm posting below shows temps further into the cab haven't pressed above freezing yet.
Title: Re: The 2020 melting season
Post by: Aluminium on May 18, 2020, 09:39:42 AM
May 13-17.

2019 (https://forum.arctic-sea-ice.net/index.php/topic,2591.msg199798.html#msg199798).

April 27 - May 17 (fast).
Title: Re: The 2020 melting season
Post by: Jim Hunt on May 18, 2020, 11:10:11 AM
Hot off NASA's presses, the current state of the sea ice in the East Siberian and Laptev Seas. Plus the (lack of?) snow cover across the adjacent land:

https://GreatWhiteCon.info/resources/arctic-sea-ice-images/summer-2020-images/#ESS
Title: Re: The 2020 melting season
Post by: peterlvmeng on May 18, 2020, 11:12:39 AM
Thanks Fri. Very interesting! We pay much attention on the air temperature and albedo effect. The ocean surface temperature is also important even decisive.
Title: Re: The 2020 melting season
Post by: uniquorn on May 18, 2020, 12:19:29 PM
The two ITPs above show the temps further West/North however you want to look at it going above freezing.
Please note that these are internal buoy temperatures for monitoring the equipment, not from an external sensor. It's likely that internal buoy temps will rise significantly above external air temps during long periods of sunshine.
They are still useful as a guide for change in temperature but should be used with caution.
Thanks to Bruce Steele for the heads up on this last year
Title: Re: The 2020 melting season
Post by: Freegrass on May 18, 2020, 01:40:56 PM
Latest Five Day Forecast
Wind + Temp @ Surface

The Kara sea will be getting a roasting in a few days from now, with the Laptev also getting its share of heat.

Positive temperatures for the Beaufort are also in the forecast.

The forecast for Fram exports looks good, with southerlies holding the ice back. But I've seen a possibility of that changing on the long term forecast.

Wind in the Bering strait will continue to come from the north until the end of the week, when a change in wind and temperature is expected.

I was under the impression from last weeks forecast that temperatures on the CAB would go down a little, but it seems they won't be dropping anytime soon.
Title: Re: The 2020 melting season
Post by: Freegrass on May 18, 2020, 03:43:23 PM
May 13-17.

2019 (https://forum.arctic-sea-ice.net/index.php/topic,2591.msg199798.html#msg199798).

April 27 - May 17 (fast).
Looking at your second animation, it looks like the entire ice pack got compacted by that giant high pressure system. Blumenkraft taught me that last season, that the ice pack tends to compact with HP systems, while LP systems tend to spread the ice out. And this clearly was proven again last week. I thought the clockwise rotation of the pack would fill up the ESS again, and it did a little, but mostly the ice was compacted towards the center, decreasing extent.
Title: Re: The 2020 melting season
Post by: Glen Koehler on May 18, 2020, 07:11:03 PM
    Excerpts from:  The Largest Arctic Science Expedition in History Finds Itself on Increasingly Thin Ice.  By Michael Kodas. May 17, 2020 in Inside Climate News. https://insideclimatenews.org/news/16052020/arctic-coronavirus-climate-science-mosaic-research (https://insideclimatenews.org/news/16052020/arctic-coronavirus-climate-science-mosaic-research) 
    The statements below from a great article about the MOSAiC expedition give insight to the current state of the ASI and the 2020 melt season to date.  The article appears to have been written when the May 11-15 weather was in the forecast, but had not happened yet, so the effects of that weather were not known.  The May 11-15 "clear-sky / warm-up / Fram-flush" almost certainly exacerbated the conditions described in the article.

--------------------
     " Even before the expedition had finished setting up its camps and instruments in November, the ice started cracking. Then, a storm sent huge rifts through the floe and knocked out the power system for several days. Cracks revealing open water repeatedly isolated Met City, sometimes forcing researchers to walk for more than an hour around the fissure to reach the site, a few hundred yards from the ship.

     "We just didn't know that we were going to face this much cracking," Shupe told me. "It really did take us by surprise, even though we knew the ice was thin, we knew the Arctic was different, it still snuck out ahead of us somehow." "

----------------------
     " An unusual weather pattern, which included the opening this spring of the largest ozone hole ever measured above the Arctic, produced winds that pushed MOSAiC's ice floe across the pole much faster than the expedition's organizers expected.

     "We have this kind of flow regime in the Arctic right now that's been really static," Shupe said. "It's stuck where it is and it's blowing us across the Arctic faster than anticipated, faster than any of the past 12 years that we used in our analysis to figure out where we would go." "

--------------------
     "Maybe the ice would slow down or even reverse direction, as it had early in the expedition, he thought. Colder weather might freeze some of the leads of open water that had fractured MOSAiC's floe. Maybe the ice would stabilize. But, increasingly, Shupe was having to come to terms with the fact that the ice floe he had hoped would be the expedition's home for a full year was unlikely to survive the summer.

     "I went into it ready to be surprised, and it still got out ahead of me," he told me. "How fragile the ice has been. I knew it was gonna be thin, but it's still thinner and more fragile than I thought it would be."  "

Title: Re: The 2020 melting season
Post by: pearscot on May 18, 2020, 08:43:36 PM
I spent the morning reading the forecasts for Barrow and Prudhoe Bay and it sounds like the region will clear out going into Wednesday. Once again, the forecasts cited the high near the East Siberian Sea.

Along with that area, I've been looking at the Kara as well given what I've seen posted here about it. In general, it appears that much of the Russian side of the arctic cannot escape direct sun. I don't know what to expect or how much this preconditions the area, but given the forecast, I think what has happened will have a significant impact on the entire ice pack's mobility.

Either way, here's a screen capture of the melt going on in that area with the red lines indicating changes in the ice color.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 18, 2020, 10:47:37 PM
Latest Five Day Forecast
Wind + Temp @ Surface

The Kara sea will be getting a roasting in a few days from now, with the Laptev also getting its share of heat.

Positive temperatures for the Beaufort are also in the forecast.

The forecast for Fram exports looks good, with southerlies holding the ice back. But I've seen a possibility of that changing on the long term forecast.

Wind in the Bering strait will continue to come from the north until the end of the week, when a change in wind and temperature is expected.

I was under the impression from last weeks forecast that temperatures on the CAB would go down a little, but it seems they won't be dropping anytime soon.

We are really close to the 2.5 months when Arctic basin surface temps remain around 0-2C all summer.

Melting really goes nuts and you reach full 24 hour periods of 1-2C and sun.
Title: Re: The 2020 melting season
Post by: Freegrass on May 18, 2020, 11:58:23 PM
We are really close to the 2.5 months when Arctic basin surface temps remain around 0-2C all summer.

Melting really goes nuts and you reach full 24 hour periods of 1-2C and sun.
True, but it looks like we'll be there a lot faster this year.

I've compared these graphs already here just last week, and today I noticed on the data thread that 2006 was 6th in extent.



(https://forum.arctic-sea-ice.net/proxy.php?request=http%3A%2F%2Focean.dmi.dk%2Farctic%2Fplots%2FmeanTarchive%2FmeanT_2020.png&hash=3f8f0ba1d1dea18e4733cf52b2e8ee08)
(https://forum.arctic-sea-ice.net/proxy.php?request=http%3A%2F%2Focean.dmi.dk%2Farctic%2Fplots%2FmeanTarchive%2FmeanT_2006.png&hash=df98242153262a8f3301922eda8a77aa)
(https://forum.arctic-sea-ice.net/index.php?action=dlattach;topic=2975.0;attach=149015;image)
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 19, 2020, 12:09:34 AM
We are really close to the 2.5 months when Arctic basin surface temps remain around 0-2C all summer.

Melting really goes nuts and you reach full 24 hour periods of 1-2C and sun.
True, but it looks like we'll be there a lot faster this year.

I've compared these graphs already here just last week, and today I noticed on the data thread that 2006 was 6th in extent.



(https://forum.arctic-sea-ice.net/proxy.php?request=http%3A%2F%2Focean.dmi.dk%2Farctic%2Fplots%2FmeanTarchive%2FmeanT_2020.png&hash=3f8f0ba1d1dea18e4733cf52b2e8ee08)
(https://forum.arctic-sea-ice.net/proxy.php?request=http%3A%2F%2Focean.dmi.dk%2Farctic%2Fplots%2FmeanTarchive%2FmeanT_2006.png&hash=df98242153262a8f3301922eda8a77aa)
(https://forum.arctic-sea-ice.net/index.php?action=dlattach;topic=2975.0;attach=149015;image)


Yeah it seems that way but unless we end up with a major dipole anomaly the last 10 days of May temps won't reach  the blue line any earlier than normal.

It's really amazing how consistent it is during the summer.

It appears to be tied to solar altitude
Title: Re: The 2020 melting season
Post by: thejazzmarauder on May 19, 2020, 12:12:35 AM
Hot off NASA's presses, the current state of the sea ice in the East Siberian and Laptev Seas. Plus the (lack of?) snow cover across the adjacent land:

https://GreatWhiteCon.info/resources/arctic-sea-ice-images/summer-2020-images/#ESS
Forgive my ignorance here, but is the explanation for the color changing from light orange to bright red and then back to orange (e.g. ESS along the coast between May 9th and 15th) simply surface melting and then re-freezing?

2nd dumb question: does surface melt earlier in the season have a mechanical impact on melt later in the season (e.g. if re-frozen ice, for some reason, melts easier than if it hadn't melted in the 1st place) or is it simply the direct impact of the albedo change occurring for the duration of surface melt (i.e. until it has re-frozen)?
Title: Re: The 2020 melting season
Post by: Glen Koehler on May 19, 2020, 12:45:38 AM
We are really close to the 2.5 months when Arctic basin surface temps remain around 0-2C all summer.
Melting really goes nuts and you reach full 24 hour periods of 1-2C and sun.

    FWIW - An unscientific "blow up the graph, add lines and eyeball it" estimate has the DMI >80N daily mean temperature at >= 0C for an average of 68 days from June 10 to August 17. 
    Using a saltwater ice melt threshold of >= -1.8C, the over-threshold season lengthens to 89 days from May 31 to August 27.
Title: Re: The 2020 melting season
Post by: Freegrass on May 19, 2020, 12:47:04 AM
Yeah it seems that way but unless we end up with a major dipole anomaly the last 10 days of May temps won't reach  the blue line any earlier than normal.

It's really amazing how consistent it is during the summer.

It appears to be tied to solar altitude
I have a funny feeling that we'll see more extreme Eurasian heat waves penetrate deep into the CAB this year. But I also know that this goes against all common knowledge, that temps in the Arctic can only go above the green line when we have a BOE.

So I'm probably wrong about this, but somehow I think it could happen. I guess we'll know in a few months from now...
Title: Re: The 2020 melting season
Post by: Often Distant on May 19, 2020, 01:55:25 AM
It's a hot day near Hudson Bay.
(https://s7.gifyu.com/images/ezgif.com-optimize-8.gif)
Title: Re: The 2020 melting season
Post by: Paul on May 19, 2020, 02:47:27 AM
We are really close to the 2.5 months when Arctic basin surface temps remain around 0-2C all summer.

Melting really goes nuts and you reach full 24 hour periods of 1-2C and sun.
True, but it looks like we'll be there a lot faster this year.

I've compared these graphs already here just last week, and today I noticed on the data thread that 2006 was 6th in extent.



(https://forum.arctic-sea-ice.net/proxy.php?request=http%3A%2F%2Focean.dmi.dk%2Farctic%2Fplots%2FmeanTarchive%2FmeanT_2020.png&hash=3f8f0ba1d1dea18e4733cf52b2e8ee08)
(https://forum.arctic-sea-ice.net/proxy.php?request=http%3A%2F%2Focean.dmi.dk%2Farctic%2Fplots%2FmeanTarchive%2FmeanT_2006.png&hash=df98242153262a8f3301922eda8a77aa)
(https://forum.arctic-sea-ice.net/index.php?action=dlattach;topic=2975.0;attach=149015;image)


Yeah it seems that way but unless we end up with a major dipole anomaly the last 10 days of May temps won't reach  the blue line any earlier than normal.

It's really amazing how consistent it is during the summer.

It appears to be tied to solar altitude

I would imagine that would be the case but what is so impressive this year is just how quick the PV has weakened everywhere and we are seeing temperatures well above normal on quite a widespread scale hence the North Pole showing as above average.

Talking of dipoles, there is a growing trend one may be on its way soon, pressure looks like its going to rise around the Beaufort sea and this could lead to the dipole set up. Bit too far out to be certain on the details at this stage though.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 19, 2020, 04:31:59 AM
2012 was the record low 2.25M.
2016 came in as a respectable 2nd with 2.45M.

Looking back over the 2016 weather charts thats really amazing.

The weather was not exceptionally warm at all.

Infact it appears that large areas of Arctic basin we're actually below normal

Well before normal.

Title: Re: The 2020 melting season
Post by: oren on May 19, 2020, 05:09:43 AM
2016 had early open water within the Arctic Ocean, and a lot of export into the Atlantic. It also had a string of powerful August cyclones, though not as effective as the 2012 GAC.
Title: Re: The 2020 melting season
Post by: blumenkraft on May 19, 2020, 08:11:49 AM
is the explanation for the color changing from light orange to bright red and then back to orange (e.g. ESS along the coast between May 9th and 15th) simply surface melting and then re-freezing?

Yes, refreezing and/or fresh snow.

Quote
does surface melt earlier in the season have a mechanical impact on melt later in the season

Yes, it's changing the albedo. More sunlight will be absorbed.
Title: Re: The 2020 melting season
Post by: El Cid on May 19, 2020, 10:52:09 AM
2016 had early open water within the Arctic Ocean, and a lot of export into the Atlantic. It also had a string of powerful August cyclones, though not as effective as the 2012 GAC.

2020 seems to have openings as well and lots of export (also 2019 fall export was strong) , soooo.....if we have some storms during summer we could see "uncharted territories" this year

 
Title: Re: The 2020 melting season
Post by: oren on May 19, 2020, 12:30:59 PM
In the first half of May 2020 was lagging 2016 and 2019 in the High Arctic Albedo-Warming Potential indicator, which basically multiplies open water and latitude-based insolation (developed and calculated by Nico Sun). However, there's a long season ahead and the recent snow conditioning over wide parts of the High Arctic is much more important at this stage.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 19, 2020, 09:08:11 PM
The 12Z EURO finally brings the hammer.

Big swing towards a late May dipole.

Verbatim the euro would walk us into June 1st primed to not only keep pace with 2012 but probably take the lead starting June.

I'll post images soon
Title: Re: The 2020 melting season
Post by: Paul on May 19, 2020, 09:13:20 PM
2016 had early open water within the Arctic Ocean, and a lot of export into the Atlantic. It also had a string of powerful August cyclones, though not as effective as the 2012 GAC.

It had that mega dipole at the end of the month I seem to recall, I think Nevan did a blog post about it at the time it was that exceptional albeit I don't think it accelerated ice losses unlike 2012s weather event.

2016 was a funny year as the ice melted out quite slowly across the basin in general(especially in the Laptev sea) but it was heavily diffused and spread out with many 'holes' in the interior of the ice pack. It's also funny because whilst 2016 finished a little bit ahead of 2019. The ice in 2019 looked somewhat more compact especially near the pole so I still have the theory, compaction and certain types of high pressure systems is not as bad as it makes out to be.

Of course one of the reasons Ive no doubt why 2019 went so low was down to the very high SSTs we had last year.

Back to the hear and now, the so called more favourable set ups of the pressure pattern turning slack does not look like lasting too long, the dipole returning is gaining strength and the Beaufort high is set to return so expect the ice to start drifting away from the coasts around there.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 19, 2020, 09:21:30 PM
You may have to click to animate.

I used the surface with 850mb temps instead of h5 and surface to highlight  the well above normal warmth with only moderate heights.

Maybe the lowered albedo is already having an affect.  I don't know.

Either way this is impressive and if it doesn't seem like it.

Remember it's only May.

Historically getting any 0C+ 850mb temps over the Arctic basin in May is almost non-existent.



(https://i.ibb.co/44bq71q/158991558630498816.gif) (https://ibb.co/JrY1K31)
Title: Re: The 2020 melting season
Post by: Glen Koehler on May 19, 2020, 11:12:09 PM
RE long-term arctic sea ice volume deviation chart
https://forum.arctic-sea-ice.net/index.php/topic,2975.msg264869.html#msg264869 (https://forum.arctic-sea-ice.net/index.php/topic,2975.msg264869.html#msg264869)

     Thanks Stephan.  I don't have the foresight to make Sept. predictions, but I'd bet dollars to doughnuts that the upside anomaly in the current chart will fall back a lot closer to the long-term trend line when the May 2020 volume data are included.
Title: Re: The 2020 melting season
Post by: jdallen on May 19, 2020, 11:53:04 PM
RE long-term arctic sea ice volume deviation chart
https://forum.arctic-sea-ice.net/index.php/topic,2975.msg264869.html#msg264869 (https://forum.arctic-sea-ice.net/index.php/topic,2975.msg264869.html#msg264869)

     Thanks Stephan.  I don't have the foresight to make Sept. predictions, but I'd bet dollars to doughnuts that the upside anomaly in the current chart will fall back a lot closer to the long-term trend line when the May 2020 volume data are included.
+1
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 20, 2020, 12:10:20 AM
After a very high maximum and a slow start to melting, the Central Seas (aka High Arctic) are losing area fast, and mostly in the Kara Sea (now lowest in the satellite record ).

I stole this chart from the data thread.

It's interesting because the Kara is about to get the steam roller.

So we can probably expect area in this region to continue to drop along record lows.

The other thing with this Russian Spring heatwave is the snow cover that remains under the big heat done will vanish quickly.

Also river ice that hasn't broken up will likely break up.


Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 20, 2020, 12:36:12 AM
The Arctic ice surface has refroze pretty well over the inner basin.

So it is pretty much impossible to see the Arctic ice surface go straight into melt in early/middle May because solar altitude isn't good enough.

And if you are wondering why the Arctic surface can see melt all the way to the pole until the end of the first week of August and between 70-80N all the way towards the end of August.

That is because:

Ice temperature (like through the ice) by then is at 0c.  Infact this heat wave certainly warmed up the ice over a large area show Even though the surface has Frozen backup that's probably only inches deep and I mean barely inches deep.

Of course over the Canadian basin the ice is still well below freezing at depth.  This is part of that pretty conditioning process.

The surface albedo is much lower by then

The ice thickness and compactness is wrecked compared to now


So while we have seen preconditioning the melt season really hasn't started yet

This means SOLAR ALTITUDE just isn't high enough until the first week of June to overcome albedo.


This means we well have to see background temps warm likely another 2-4C around the ice in May and snow cover to vanish at least a week earlier than the current earliest before we see ice volume sustainably go lower than it already has.

This means a total melt out isn't likely until 2035-2040 or later

Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 20, 2020, 12:40:33 AM
I forgot to add the graphic.

We can see the change right back to frozenish compared to 3 days ago
Title: Re: The 2020 melting season
Post by: Aluminium on May 20, 2020, 09:14:06 AM
May 15-19.

2019 (https://forum.arctic-sea-ice.net/index.php/topic,2591.msg200104.html#msg200104).
Title: Re: The 2020 melting season
Post by: Wildcatter on May 20, 2020, 09:58:32 AM
Looks like there's a good chance of open water from Kara -> Laptev in a couple days. Winds today will help pry it open a little more as heat starts over Kara. The heat+winds keeps moving, advecting from Eurasia, over Kara, Severnaya, Laptev. Winds likely to start advancing the bite.. Will be interesting to see what happens with the ESS ice with wind coming up, system also might want to migrate in that direction, Severnaya leads might be interesting too.

In 3-4 days heat should be starting to reach Chukchi, Alaska warming up, wind stress on the Beaufort ice + warmer temps. With the winds from the Laptev as well, some anti-cyclonic forcing, probably won't be too long before the coastal ice gives.

It's looking like there's a pretty good chance we go into June with no real landfast ice, besides the CAA. I don't think that's ever happened before.
Title: Re: The 2020 melting season
Post by: pauldry600 on May 20, 2020, 11:31:19 AM
It's looking like there's a pretty good chance we go into June with no real landfast ice, besides the CAA. I don't think that's ever happened before


I dont think this is at all likely. Ice always finds some coast to grip but it is more mobile I admit.
Title: Re: The 2020 melting season
Post by: marcel_g on May 20, 2020, 02:52:40 PM

This means SOLAR ALTITUDE just isn't high enough until the first week of June to overcome albedo.


This means we well have to see background temps warm likely another 2-4C around the ice in May and snow cover to vanish at least a week earlier than the current earliest before we see ice volume sustainably go lower than it already has.

This means a total melt out isn't likely until 2035-2040 or later

Interesting idea. Wouldn't the amount of cloud cover and melt ponds during the period of roughly late May to the third week of July be more significant factors that determine higher latitude melt out, rather than air temperature? Mainly by increasing the amount of solar energy that gets through the ice and then does most of the overall melting by bottom melt. I was under the impression that bottom melt did a larger proportion of the melting over the course of the melt season, rather than warmer air over the ice. My assumption is that lot more energy is transferred into the system from sunlight into water than is transferred in via warm air over ice.

Maybe I'm misreading what you're saying? Maybe you're saying that we need 2-4C temperature increase in order to achieve early enough preconditioning and melt ponds to allow enough solar energy through the ice to achieve total melt out above 80 degN?

If so, a normal summer until then would see ice melt rapidly at lower latitudes, but generally stall around 70-80 degN?

Unless there is an unusually sunny period between the last week of May and the third week of July, in that case the melt out might go a lot further north.

Title: Re: The 2020 melting season
Post by: Stephan on May 20, 2020, 06:03:47 PM
RE long-term arctic sea ice volume deviation chart
https://forum.arctic-sea-ice.net/index.php/topic,2975.msg264869.html#msg264869 (https://forum.arctic-sea-ice.net/index.php/topic,2975.msg264869.html#msg264869)

     Thanks Stephan.  I don't have the foresight to make Sept. predictions, but I'd bet dollars to doughnuts that the upside anomaly in the current chart will fall back a lot closer to the long-term trend line when the May 2020 volume data are included.
The statistics say that it is likely that Sep (and Jul, Aug, Oct) volume anomaly will be below the linear trend line. This has happened from 2009 on, with exceptions in 2015 and 2018. In those two years the volume anomaly was around the long term linear trend line.
Title: Re: The 2020 melting season
Post by: pearscot on May 20, 2020, 06:07:13 PM
I realize this measurement could be more accurate, but look at the size of this iceberg which was ejected out of the Fram. It made some rapid progress south and is now just floating off the eastern coast. I will continue to watch it until its eventual demise/

Title: Re: The 2020 melting season
Post by: blumenkraft on May 20, 2020, 06:36:47 PM
Cool, idea Pearscot. Keep us updated. :)
Title: Re: The 2020 melting season
Post by: thejazzmarauder on May 20, 2020, 06:42:51 PM
I realize this measurement could be more accurate, but look at the size of this iceberg which was ejected out of the Fram. It made some rapid progress south and is now just floating off the eastern coast. I will continue to watch it until its eventual demise/
That's larger than the state of Rhode Island
Title: Re: The 2020 melting season
Post by: bbr2315 on May 20, 2020, 08:44:34 PM
The snow melt vs 2019 has been very very bad. Wow.

(https://im2.ezgif.com/tmp/ezgif-2-6edb6cd04055.gif)

We are probably in for unprecedented conditions imminently. And massive summertime wildfires across the areas that have played host to largest + departures / early snowmelt across Eurasia.
Title: Re: The 2020 melting season
Post by: Freegrass on May 20, 2020, 10:18:15 PM
Holy guacamole...  :o

This is in no way certain. It's still far out into the future. But if there's any truth to this...
Hay naku buhay!  :'(
Title: Re: The 2020 melting season
Post by: Freegrass on May 20, 2020, 10:49:24 PM
The little floe that could (hold back a giant ice bridge in the ESS) just gave way...  :'(
Title: Re: The 2020 melting season
Post by: ReverendMilkbone on May 21, 2020, 12:40:33 AM
The snow melt vs 2019 has been very very bad. Wow.

(https://im2.ezgif.com/tmp/ezgif-2-6edb6cd04055.gif)

We are probably in for unprecedented conditions imminently. And massive summertime wildfires across the areas that have played host to largest + departures / early snowmelt across Eurasia.

BBR the image link is broken, can you please resubmit?
Title: Re: The 2020 melting season
Post by: bbr2315 on May 21, 2020, 12:47:18 AM
The snow melt vs 2019 has been very very bad. Wow.

(https://im2.ezgif.com/tmp/ezgif-2-6edb6cd04055.gif)

We are probably in for unprecedented conditions imminently. And massive summertime wildfires across the areas that have played host to largest + departures / early snowmelt across Eurasia.

BBR the image link is broken, can you please resubmit?
Alas, just go to this link & scroll between 2020->2019.

https://worldview.earthdata.nasa.gov/?v=-2533595.533333333,765873.5333333337,2602788.466666667,3344766.3333333335&p=arctic&l=Reference_Labels(hidden),Reference_Features(hidden),Coastlines,MODIS_Aqua_CorrectedReflectance_TrueColor(hidden),MODIS_Terra_CorrectedReflectance_TrueColor
Title: Re: The 2020 melting season
Post by: wdmn on May 21, 2020, 01:29:02 AM
According to Nico Sun's website, 2020 is closing the gap with 2016 for the lowest sea ice area for this time of year. In addition, compaction (which is area/extent) is quite a bit lower than in 2016 at this time.

Title: Re: The 2020 melting season
Post by: pearscot on May 21, 2020, 03:00:56 AM
Wow, that downturn is quite surprising. I mean I expected to see it fall, but not that sharply.

I suppose the one thing I've been thinking about recently is how both the East Siberian and Kara Sea have recieved quite a bit of direct sunlight on the 'small' (relatively speaking) amount of open water and what the implications there are. I know and it has been cited by others in this thread that the central arctic is still cold and below freezing, so while the ice surface has been going thru some freeze/refreeze/snow during May, I can't help but wonder just how much the warming of those seas will melt the surrounding ice there actually is?

Granted waves, wind, and bottom melt are always factors, but those two regions are really fascinating to me this year. Not to mention, the breakdown of land-fast ice has allowed for not only the entire pack rotate into those aforementioned seas, but I wonder how much the injection of ice into those areas will be melted as large cracks continue to appear above Greenland/Canada.

I don't know...I'm not trying to claim stuff I do not yet know, but for the most part, where is is open water indicated in the arctic it's anomalously warm. I also find it REALLY interesting to see 2016 being cited right now for comparisons because I have noticed quite a few similarities (visually speaking) on worldview from 2016 too. Additionally, the Bering Sea of 2020 mirrors that of 2012. Still way too early to know, but with the extended forecast for Barrow predicting a building high over the central arctic in conjunction with more sun and warmth, there is still just so much to focus on right now. 

(https://www.ospo.noaa.gov/data/cb/ssta/ssta.daily.current.png)
Title: Re: The 2020 melting season
Post by: bbr2315 on May 21, 2020, 05:18:31 AM
The Laptev, Kara, and Barents should all be near 0 by 6/30 or earlier. I would imagine that would be a first?

(https://www7320.nrlssc.navy.mil/GLBhycomcice1-12/navo/arcticictn/nowcast/ictn2020051912_2020052000_930_arcticictn.001.gif)

The integrity of the ice on the Eurasian side is already worst on record, combined with the very early snow melt vs normal in the highest Russian Arctic, it will be blasted by continental heat through the end of June at varying intervals and is likely to disappear sooner than later. This leaves a clear and obviously wide front well into the CAB come July, IMO.

On the plus side, HYCOM shows a LOT more volume in the Beaufort Gyre / pushed against the CAA. It looks like where the ice was retrenched should easily be safe no matter what, with wide areas of 3M+ thickness now appearing.
Title: Re: The 2020 melting season
Post by: binntho on May 21, 2020, 06:37:42 AM
I realize this measurement could be more accurate, but look at the size of this iceberg which was ejected out of the Fram. It made some rapid progress south and is now just floating off the eastern coast. I will continue to watch it until its eventual demise/

I was going to quibble (as usual) that it was an ice floe and not an iceberg. Then I started to think that in the Antarctic, bigger icebergs than this have been seen. So what about the Arctic, what is the biggest iceberg on record there? Turns out that it is a 100 square mile chunk that broke off Petermann glacier in 2010.

So this is a floe, quite definitely, based on size alone. And if a measurable iceberg were to break off somewhere and start drifting down the Fram I'm sure we would hear about it.

Some 300 miles further south I find a pair of floes, 600 and 400 sqmi respectively, so I guess these big floes are not that unique. But they are good fun, being easy to track.
Title: Re: The 2020 melting season
Post by: oren on May 21, 2020, 08:09:53 AM
The Laptev, Kara, and Barents should all be near 0 by 6/30 or earlier. I would imagine that would be a first?
The Barents is always near 0 by June 30th. The Kara could conceivably get near 0 by that date, seeing as it started early. I will go on record here to claim there is zero probability of the Laptev doing so, regardless of what Hycom may indicate.
Title: Re: The 2020 melting season
Post by: wdmn on May 21, 2020, 09:10:25 AM
This is outside of my comfort zone to post about, but I'm sort of surprised by the lack of talk about the 00Z GFS forecast over the next 7 days. Starting Saturday we see above zero Avg. temperatures start to creep in over the Beaufort, the Laptev and the Kara, and then it just keeps coming.

By the 28th almost the whole arctic (excepting the CAA) is at or above 0 avg temperature.
Title: Re: The 2020 melting season
Post by: Pavel on May 21, 2020, 09:28:06 AM
This is outside of my comfort zone to post about, but I'm sort of surprised by the lack of talk about the 00Z GFS forecast over the next 7 days. Starting Saturday we see above zero Avg. temperatures start to creep in over the Beaufort, the Laptev and the Kara, and then it just keeps coming.

By the 28th almost the whole arctic (excepting the CAA) is at or above 0 avg temperature.
It's not 100% reliable but the GFS snow depth forecast supposes the massive meltponding in the inner basin even before June is starting. One can see on the Worldview how quickly the land snow melts each day in northern Siberia
Title: Re: The 2020 melting season
Post by: ArcticMelt2 on May 21, 2020, 01:15:04 PM
It's not 100% reliable but the GFS snow depth forecast supposes the massive meltponding in the inner basin even before June is starting. One can see on the Worldview how quickly the land snow melts each day in northern Siberia

In recent years, the Canadian part of the Arctic has consistently been distinguished by the largest snow anomaly in a big way. Direct evidence of aerosol effects from the burning of Canadian bitumen.

<Please do not promote haywire theories on the main thread. This can be discussed in a different thread but needs to be supported with reasoning and evidence. O>
Title: Re: The 2020 melting season
Post by: ArcticMelt2 on May 21, 2020, 01:20:13 PM
A more accurate depiction of snow anomalies in Canada.
Title: Re: The 2020 melting season
Post by: Butterflyy on May 21, 2020, 02:48:50 PM
Paul Beckwith from Univeraity of Ottawa  was putting forward a theory that a shift of the polar vortex toward groenland as the snow melt was going to happen. 

His point was that the core of the ice will over time only be the glacier mass, and Jet stream will migrate according to this.  This should make the north East canada part more exposed to lower temperature than rest of the surrounding region.

IMO  the lower temperature anomalies observed in the last years in north eastern canada may be due to this new pattern developping. THe increased snow cover may be more related to this than aerosols from bitumen burnt.
Title: Re: The 2020 melting season
Post by: oren on May 21, 2020, 03:06:31 PM
Welcome Butterflyy.
This theory is best discussed elsewhere. Note that its more extreme version (the "Quebec reglaciation") has been promoted all over the forum by a certain user  and is frowned upon by the new moderator.  8)
Title: Re: The 2020 melting season
Post by: PragmaticAntithesis on May 21, 2020, 05:57:15 PM
Welcome Butterflyy.
This theory is best discussed elsewhere. Note that its more extreme version (the "Quebec reglaciation") has been promoted all over the forum by a certain user  and is frowned upon by the new moderator.  8)

Anyone know where I can find a thread discussing/debunking this and similar theories? The idea that, in a post-BOE world, the air above land ice will become colder than air over water further north is an interesting one...
Title: Re: The 2020 melting season
Post by: wdmn on May 21, 2020, 08:31:29 PM
GFS and area data suggest that 2020 will be in first place by this time next week, with an uptick in losses in the Beaufort and Hudson Bay, along with the Siberian side over that time.
Title: Re: The 2020 melting season
Post by: bbr2315 on May 21, 2020, 09:08:59 PM
The % decline in Hudson is melt ponding, not disintegration. CICE actually shows most of the ice "flashing" is well over 1M in thickness. It will still melt out anyways at some point, but I am unsure if this year will see very late retention or not -- the volume / thickness could argue for this, although surface conditions in HB itself would argue to the contrary (snowcover surrounding HB also factor in favor of +ice into August).
Title: Re: The 2020 melting season
Post by: Aluminium on May 21, 2020, 09:25:32 PM
Dikson Island (Kara) had new highest of May, +11.1°C. Dew point was above +6°C.
Title: Re: The 2020 melting season
Post by: Paul on May 21, 2020, 10:23:09 PM
Dikson Island (Kara) had new highest of May, +11.1°C. Dew point was above +6°C.

It has been quite an exceptional warm up across that part of the world, less snowcover means more heat and so on and so forth but even so, the lack of snowcover for this time of year is quite exceptional.
Title: Re: The 2020 melting season
Post by: Niall Dollard on May 22, 2020, 01:29:25 AM
Dikson Island (Kara) had new highest of May, +11.1°C. Dew point was above +6°C.

It has been quite an exceptional warm up across that part of the world, less snowcover means more heat and so on and so forth but even so, the lack of snowcover for this time of year is quite exceptional.

Dikson began the day with 10cm snowcover. I expect today's warm max will leave only a small  amount for Friday.

Looking back over previous years, Dikson would typically have between 30cm  and 70cm of snow cover at this time of year.

As we have said many times before in this thread the state of ice and snow on the Russian side is very poor this year. Starting from a record mild winter in western Russian, the heat has been steadily building up and expect many more frequent heat attacks on the Arctic east of 0 deg longitude.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 22, 2020, 04:05:48 AM

This means SOLAR ALTITUDE just isn't high enough until the first week of June to overcome albedo.


This means we well have to see background temps warm likely another 2-4C around the ice in May and snow cover to vanish at least a week earlier than the current earliest before we see ice volume sustainably go lower than it already has.

This means a total melt out isn't likely until 2035-2040 or later

Interesting idea. Wouldn't the amount of cloud cover and melt ponds during the period of roughly late May to the third week of July be more significant factors that determine higher latitude melt out, rather than air temperature? Mainly by increasing the amount of solar energy that gets through the ice and then does most of the overall melting by bottom melt. I was under the impression that bottom melt did a larger proportion of the melting over the course of the melt season, rather than warmer air over the ice. My assumption is that lot more energy is transferred into the system from sunlight into water than is transferred in via warm air over ice.

Maybe I'm misreading what you're saying? Maybe you're saying that we need 2-4C temperature increase in order to achieve early enough preconditioning and melt ponds to allow enough solar energy through the ice to achieve total melt out above 80 degN?

If so, a normal summer until then would see ice melt rapidly at lower latitudes, but generally stall around 70-80 degN?

Unless there is an unusually sunny period between the last week of May and the third week of July, in that case the melt out might go a lot further north.


That's exactly right.

Solar altitude doesn't get high enough to overcome the snow albedo effect until the first week of June.

We had 4-5 days in a row of 24 sun over large parts of the basin between 75-90N.

And albedo did take a hit but only a little bit.

The full wetness look on satellite never materialized.

And once temps slightly cooled and sun vanished the surface froze back up.

And yeah for bottom melt direct solar insolation is required.

But warm air advection can ravage the surface way now than sun because the solar ALTITUDE always sucks North of 70.

I live at 38.75N in the United States.

And right now the sun during peak heating is almost directly overhead.

A couple days ago we had very strong CAA... Temps were in the mid to upper 50s which is currently about 20-23F below normal.

We had low level cumulous clouds rotating in from the NW.

It was a very cold day.  Or felt cold considering what time of year it is.

Well the cumulous deck covered about 65 percent of the sky.

And when the sun would peak out it instantly felt like the gates of hell were breathing fiire down on your skin.

In January when its 50F under the same conditions.

And the sun breaks out you feel essentially no difference on your skin.

It doesn't start becoming very noticeable until early February.

By March is very noticeable.

Anyways solar altitude between 80-90N barely goes above 25° and I believe at the pole it never rises above 23.5° but I may be incorrect about that.

My point is to melt out the 3M+ MYI in the CAB we will definitely need big time dipole sun in June/July.

But also great preconditioning.

It would help immensely to see snow cover over the CAA be essentially gone by June 1st.

And then we would need not just sun.  But a HP/SLP set up that brings a surface wind fetch that origionates West and Northwest of the Hudson Bay over the last lands of Canada.

This allows the low level air mass to heat up dramatically more than a flow either over the Hudson Bay, East of there over the Baffin and CAA waterways, or West over the Beaufort or Western CAA waterways.

This route if it could become established for more than a couple days could be devestating to the CAB.

In late July 2012 a similar set up took place between July 29-Aug 4th. 

It completely destroyed a large part of the Western CAB.


Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 22, 2020, 04:23:30 AM
This is outside of my comfort zone to post about, but I'm sort of surprised by the lack of talk about the 00Z GFS forecast over the next 7 days. Starting Saturday we see above zero Avg. temperatures start to creep in over the Beaufort, the Laptev and the Kara, and then it just keeps coming.

By the 28th almost the whole arctic (excepting the CAA) is at or above 0 avg temperature.
It's not 100% reliable but the GFS snow depth forecast supposes the massive meltponding in the inner basin even before June is starting. One can see on the Worldview how quickly the land snow melts each day in northern Siberia

Unfortunately there is no way the ice on the Atlantic side is has that much snow depth.  So it's equally likely the snow depth on the Pacific side is no where near that low.

I'd love for reliable snow depth over the ice.


Title: Re: The 2020 melting season
Post by: 1rover1 on May 22, 2020, 05:06:13 AM
For some real time images of the snow in the CAA there are a few good cameras at Canadian airports on the Nav Canada WxCam site.     

https://www.metcam.navcanada.ca/hb/index.jsp?lang=e




Title: Re: The 2020 melting season
Post by: Aluminium on May 22, 2020, 07:33:56 AM
May 17-21.

2019. (https://forum.arctic-sea-ice.net/index.php/topic,2591.msg200485.html#msg200485)
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 22, 2020, 08:10:44 AM
The gfs in the long range shows the pattern I'm talking about for the CAB/CAA.

Before this a quasi dipole does  form
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 22, 2020, 08:13:21 AM
Snow cover has freaking vanished.

Good lord
Title: Re: The 2020 melting season
Post by: VeliAlbertKallio on May 22, 2020, 08:56:24 AM
The solar altitude idea is quite interesting as well as the projection of ice remaining 80-90 degrees to the north until perhaps 2040 as a consequence of low solar angle in the high latitude. I have been looking at this issue from perspective of sea ice stability and sea ice variabilities. I suspect as the mobility is increasing, sea ice is pushed increasingly to open areas as sea ice scattering increases.

To resolve half way the above problem, we at Sea Research Society, would be grateful if someone with skills on spreadsheets and data could put out a graph which shows the minimum-maximum sea ice area on each day. The simplest this type graph would be to show each date's highest-ever and lowest-ever value and the relation of current year's reading (its place) against these two boundaries. This is a very primitive and not too helpful -- except for public purposes to show current years position in media. For the general public having a set of multiple curves is confusing and newspaper space limits the size of graph in print. If a graph of highest-lowest ever is made you can fit it in 1-2 inch graph in magazine, for newspaper there are a bit more options but generally I believe most people find extra curves confusing. They don't have scientific value, just informative one as printing space is limited.

A more useful graph for ASIF community would be one that shows 5 / 10-year moving average of sea ice area variability. This could give us projections how broad range of outcomes of sea ice scattering and melt would be in future. Walt Meier just wrote a paper on sea ice movement increasing 10% per decade. Suggested chart, I suggest, could provide indication how sea ice area variability has evolved in time: this changing variability unfolds future in case the moving averages reveal a widening outcome spectrum. I suspect huge fanning ahead in possible sea ice extents.

Unfortunately we at SRS are not able to do it as our strength areas are in marine archeology and anthropology where we are world leaders in a deep diving. Our teaching programme for deep divers for oil rigs is just 5th accepted centre of learning in whole USA (including US Navy). Thus we have had archaeological excavations conducted under 180 metres below sea surface from sea bed pressurised cabin. This makes us the only archaeological organisation to excavate former Palaeolithic sites at Last Glacial Maximum at 120-130 metres below sea level. But we are hampered with funding to our work.

Palaeolithic archaeological work is important for understanding how fast sea level rose in the past:

There is a worrying amount of sites where pots and pans are left behind that suggests huge displacement events by collapsing ice sheets that are not at all in current geophysical model. This imply that they simply must be wrong. Valuable items are never left behind if people can collect them! I have been warning at UK Houses of Parliament of various failings and overconfidence of geophysicists. This must remain SRS' focus to warn about problem geophysical models do not capture.

The other similar problem is the pulverising effect which is lacking in Pleistocene sites when it shouldn't. If sea level changes slowly, the waves excavate soils and pulverise even strong buildings. This has not happened in the ice Ages, and many buildings over large areas remain immersed intact in water (unless a by-passing trawler net has caught and damaged them). From geophysical point of view I've captured and offered explanation to above in my Parliament evidence giving most recently: https://www.academia.edu/37157851/Our_Changing_Climate_in_Action_the_Risk_of_Global_Warming_and_the_Environmental_Damage_from_the_Rising_Ocean_Water_Table_Sustainable_Seas_Enquiry_Written_evidence_submitted_by_Veli_Albert_Kallio_FRGS_SSI0121_Ordered_to_be_published_23_May_2018_by_the_House_of_Commons

I have not been contributing graphs here in ASIF last four years. The last one of mine being corrections to US Defence Meteorological Satellite Program (DMSP) F-17 satellite when its Special Sensor Microwave Imager and Sounder (SSMIS) data began providing erratic passive microwave brightness temperatures (and its derived Arctic and Antarctic sea ice products). President Trump then stupidly if not disgustingly trashed US$ 400 million US Navy replacement satellite on ground with his typical arrogant style thus wasting taxpayers money (much like ensuring coronaviruses to populate the US and reduce human emissions).

To resolve issues discussed here, we need a new type of graph that shows the changing variability of spectrum of sea ice area and extent outcomes. I expect this rainbow be widening and I don't believe sea ice remaining safe until 2040. I understand that the idea of ice remaining was flouted as theoretical idea rather than expected outcome knowing the decreasing barriers as ocean opens and ice has more space to move around, ultimately the islands left as the last constraint.

On geoengineering I've lobbied bridge suspension cabling with lower able pontoons with compressed air to be installed Ellesmere Island - Hans Island - Greenland to reduce ice flow on the Nares Strait and also between the Queen Elizabeth islands to hold sea ice back for shipping lane. So far, I have not gathered great interest on neither idea but they could be used to control southward ice loss.

Based on our experience, we expect Arctic Ocean sea ice loss be catastrophic for North Greenland's ice sheet. Initially the lake-snow effect of the Arctic Ocean (studied by Maurice Ewing and William Donn in 1950's as a potential cause for the ice ages), could lift enough snow from the Arctic Ocean to reverse for a brief moment the sea level rise, then followed by castastrophic collapses due to meltwater build up under and within the ice sheet - suddenly then pushing ocean water table up, with people running from their homes and thus leaving household valuables behind. We can still find these artefacts in original contexts indicating that at least in the Indian Ocean people had no time but just run away.

We do not hear from these just because few people dig Palaeolithic as there is 'no gold and silver' and the work in ocean depths is costly + dangerous with each additional metre of water. In Indian Ocean sites strong currents and no visibility deters divers exploring sites, plus the high cost of this type of deep diving work. The fact we don't hear about it, doesn't mean that the problem does not exist.

Veli Albert Kallio, FRGS
Sea Research Society, Vice President
Environmental Affairs Department
https://en.wikipedia.org/wiki/Sea_Research_Society
Solar altitude doesn't get high enough to overcome the snow albedo effect until the first week of June.
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 22, 2020, 10:12:29 AM
Great post above.

Don't have time attm to respond.

But I will say the 00z euro brings the heat to the cab, Beaufort, Chuckchi, and part of the CAA.

The winds are compacting slowly turning from the Beaufort to the Pacific side in general.

Quite warm flow downsloping off those Alaska mountains
Title: Re: The 2020 melting season
Post by: oren on May 22, 2020, 10:14:27 AM
VAK, parts of your post are very off-topic here. Some belong in "When will the Arctic go ice-free", "Geoengineering", "Archaeology/Paleontology news". As this is a rare occurrence I will let it stand, but more such posts will have to be moved/edited/deleted,
Title: Re: The 2020 melting season
Post by: Phoenix on May 22, 2020, 10:17:41 AM
The combined NSIDC sea ice area in the Beaufort and Chukchi is 1,585k km2. At this time last year, was 1,317k km2.

The Pacific side is clearly presenting a larger buffer to penetration of some areas where ice is most likely to remain at seasons end (N. Beaufort, N. CAA and western CAB).

I'm keeping my eye on the deep CAB boundary on the Siberian and Atlantic sides as the keys to this season. There is already open water at the boundary line ~ 82N north of FJL. When / where will the open water penetrate into the deep CAB?

edit: while acknowledging the difficulties associated with setting a season end minimum record in 2020, there's a good likelihood of setting the pace with date records in June, July and early August. We're approaching the portion of the calendar where 2016 lost momentum. 
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 22, 2020, 11:06:16 AM
The combined NSIDC sea ice area in the Beaufort and Chukchi is 1,585k km2. At this time last year, was 1,317k km2.

The Pacific side is clearly presenting a larger buffer to penetration of some areas where ice is most likely to remain at seasons end (N. Beaufort, N. CAA and western CAB).

I'm keeping my eye on the deep CAB boundary on the Siberian and Atlantic sides as the keys to this season. There is already open water at the boundary line ~ 82N north of FJL. When / where will the open water penetrate into the deep CAB?

edit: while acknowledging the difficulties associated with setting a season end minimum record in 2020, there's a good likelihood of setting the pace with date records in June, July and early August. We're approaching the portion of the calendar where 2016 lost momentum.

Last year having slightly more open water in the Chuchki doesn't matter.

So far this year has seen unprecedented preconditioning that no modern year has ever seen.

The Eurasian snow cover has straight vanished.

And now the weather is crushing the laptev and Kara and the Beaufort, Chuckchi, Western cab is about to see about perfect preconditioning heading into June.

We don't know what is going to happen in June but so far we are likely going into June in best modern set up to ravage the inner Arctic basin.
Title: Re: The 2020 melting season
Post by: VeliAlbertKallio on May 22, 2020, 11:19:16 AM
My apologies of banding things together. I should have been more pointed just to state that I have noticed a lack of graphs on ASIF that show evolution of sea ice area and extent variability rising/lowering/staying same over moving 5 and 10 year periods whichever shows better where we are going. If that got lost, then I perhaps shoot my own foot. (I wish I'd be able to create such graphs.)

VAK, parts of your post are very off-topic here. Some belong in "When will the Arctic go ice-free", "Geoengineering", "Archaeology/Paleontology news". As this is a rare occurrence I will let it stand, but more such posts will have to be moved/edited/deleted,
Title: Re: The 2020 melting season
Post by: uniquorn on May 22, 2020, 11:21:17 AM
Beaufort Sea yesterday, greyscale linear contrast to show floe characteristics. https://go.nasa.gov/2zUX3MR
click for full resolution
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 22, 2020, 11:49:33 AM
Beaufort Sea yesterday, greyscale linear contrast to show floe characteristics. https://go.nasa.gov/2zUX3MR
click for full resolution
there is a torrid downslope coming to the Beaufort.

The snow on land along the coast is toast over the next week.

The Mackenzie river delta will start to rapidly dethaw.

Assuming heights and winds come as forecasted the factor deciding how things will play out is how much sun will be accompanying the WAA downslope.

Currently solar altitude at Barrow Alaska goes above 30° for 7.5 hours.

23-25° is essentially the magic number for impactful sun on the surface.

30°+ is plenty to go to work smoking the ice.

By June 1st that touches 40° and spends 12 hours above 30°

The peak today is 39°

Any afternoon sun will hammer albedo at this point
Title: Re: The 2020 melting season
Post by: Phoenix on May 22, 2020, 12:38:50 PM

We don't know what is going to happen in June but so far we are likely going into June in best modern set up to ravage the inner Arctic basin.

I guess that's a matter of opinion. 2012 and 2016 had very weak freezing seasons which preceded them and set the stage with thinner ice. By comparison, 2020 was a much better freezing season. Hoping for a mid-May PIOMAS volume update which gives us a better idea of thickness.
Title: Re: The 2020 melting season
Post by: binntho on May 22, 2020, 12:51:45 PM
there is a torrid downslope coming to the Beaufort.
<snip>
Assuming heights and winds come as forecasted the factor deciding how things will play out is how much sun will be accompanying the WAA downslope.

Friv, I am very grateful for how much more work you are putting into explaining things to us footlings trying to follow your soaring flight.

But I'm still at loss sometimes. What is a downslope, and what do you mean by "WAA"?
Title: Re: The 2020 melting season
Post by: SimonF92 on May 22, 2020, 12:53:22 PM

We don't know what is going to happen in June but so far we are likely going into June in best modern set up to ravage the inner Arctic basin.

I guess that's a matter of opinion. 2012 and 2016 had very weak freezing seasons which preceded them and set the stage with thinner ice. By comparison, 2020 was a much better freezing season. Hoping for a mid-May PIOMAS volume update which gives us a better idea of thickness.

2012 and 2016 were middle of the pack in terms of their freezing seasons. 2014, 2017, 2018 were just as bad
Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 22, 2020, 01:00:42 PM

We don't know what is going to happen in June but so far we are likely going into June in best modern set up to ravage the inner Arctic basin.

I guess that's a matter of opinion. 2012 and 2016 had very weak freezing seasons which preceded them and set the stage with thinner ice. By comparison, 2020 was a much better freezing season. Hoping for a mid-May PIOMAS volume update which gives us a better idea of thickness.

That isn't what we use to define a melting season.

Everyone agrees that 2007 was the melt season on record.

Because the conditions for melt June-Aug were amazing.

If we had an exact repeat of 2007 weather wise we would crush 2012 lows.

The preconditioning that has taken place and is still to come taking place is putting 2020 in one of the best spots  going into June in modern times.

2020 having slightly more ice thickness means nothing if we have melt weather going into June.




Title: Re: The 2020 melting season
Post by: Frivolousz21 on May 22, 2020, 01:08:01 PM
there is a torrid downslope coming to the Beaufort.
<snip>
Assuming heights and winds come as forecasted the factor deciding how things will play out is how much sun will be accompanying the WAA downslope.

Friv, I am very grateful for how much more work you are putting into explaining things to us footlings trying to follow your soaring flight.

But I'm still at loss sometimes. What is a downslope, and what do you mean by "WAA"?

Thank You!

Downslope is the winds coming down from a higher elevation to a lower.

This is what Google says.

Downsloping is the process that occurs when a stream of air is forced to descend a mountain. As the air descends, it undergoes a series of changes that result in a warming/drying effect. This series of changes is known as adiabatic warming. So what does that mean?Dec 29, 2018



WAA stands for WARM AIR ADVECTION.
simple meaning for warm air advection is warm air moving into an area replacing the previous cooler air mass.

As the forecast gets going the winds blow down off the mountains and warn and dry out.

Bringing WAA to the Arctic basin
Title: Re: The