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Freegrass

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Re: The 2020 melting season
« Reply #450 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?
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Milwen

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Re: The 2020 melting season
« Reply #451 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.


oren

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Re: The 2020 melting season
« Reply #452 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.

blumenkraft

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Re: The 2020 melting season
« Reply #453 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.

F.Tnioli

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Re: The 2020 melting season
« Reply #454 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.
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pearscot

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Re: The 2020 melting season
« Reply #455 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. 
pls!

Niall Dollard

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Re: The 2020 melting season
« Reply #456 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.

VaughnAn

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Re: The 2020 melting season
« Reply #457 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.

Jim Hunt

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Re: The 2020 melting season
« Reply #458 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

Reality is merely an illusion, albeit a very persistent one - Albert Einstein

Pavel

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Re: The 2020 melting season
« Reply #459 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

gandul

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Re: The 2020 melting season
« Reply #460 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.



Whether that's snow cover loss, or material deposition, this is very anomalous.
Wasn't there a recent wave above 0C?

gandul

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Re: The 2020 melting season
« Reply #461 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.  ;)

F.Tnioli

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Re: The 2020 melting season
« Reply #462 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.
To everyone: before posting in a melting season topic, please be sure to know contents of this moderator's post: https://forum.arctic-sea-ice.net/index.php/topic,3017.msg261893.html#msg261893 . Thanks!

The Walrus

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Re: The 2020 melting season
« Reply #463 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.

Pavel

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Re: The 2020 melting season
« Reply #464 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.



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

gandul

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Re: The 2020 melting season
« Reply #465 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.

uniquorn

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Re: The 2020 melting season
« Reply #466 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

kassy

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Re: The 2020 melting season
« Reply #467 on: April 25, 2020, 11:08:42 PM »
It is OT.
<Thank you Kassy. O>
« Last Edit: April 25, 2020, 11:29:51 PM by oren »
Þetta minnismerki er til vitnis um að við vitum hvað er að gerast og hvað þarf að gera. Aðeins þú veist hvort við gerðum eitthvað.

Niall Dollard

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Re: The 2020 melting season
« Reply #468 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.


VeliAlbertKallio

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Re: The 2020 melting season
« Reply #469 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.
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Aluminium

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Re: The 2020 melting season
« Reply #470 on: April 26, 2020, 09:45:50 AM »
April 20-25.

2019.

grixm

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Re: The 2020 melting season
« Reply #471 on: April 26, 2020, 09:49:52 AM »
April 20-25.


Wow, sea ice has hit Bear Island

oren

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Re: The 2020 melting season
« Reply #472 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.

gandul

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Re: The 2020 melting season
« Reply #473 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.


Stephan

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Re: The 2020 melting season
« Reply #474 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  :)
It is too late just to be concerned about Climate Change

be cause

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Re: The 2020 melting season
« Reply #475 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.
2007 + 5 = 2012 + 4 = 2016 + 3 = 2019 + 2 = 2021 
 (phew)

blumenkraft

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Re: The 2020 melting season
« Reply #476 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

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://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.

blumenkraft

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Re: The 2020 melting season
« Reply #477 on: April 26, 2020, 06:33:37 PM »
7-day hindsight mean temperature & DMI 80°N 2m Temperature

blumenkraft

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Re: The 2020 melting season
« Reply #478 on: April 26, 2020, 06:34:08 PM »
Ice drift map.

blumenkraft

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Re: The 2020 melting season
« Reply #479 on: April 26, 2020, 06:34:42 PM »
Fram export via SAR.

johnm33

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Re: The 2020 melting season
« Reply #480 on: April 26, 2020, 09:29:03 PM »
Beaufort ice is shattered, won't hold a crack just spreads out, which implies it's very fluid.

pearscot

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Re: The 2020 melting season
« Reply #481 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.

pls!

uniquorn

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Re: The 2020 melting season
« Reply #482 on: April 26, 2020, 10:43:19 PM »
Beaufort 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.

Glen Koehler

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Re: The 2020 melting season
« Reply #483 on: April 27, 2020, 02:50:58 AM »
April 20-25.
2019.
      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?

Niall Dollard

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Re: The 2020 melting season
« Reply #484 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/

F.Tnioli

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Re: The 2020 melting season
« Reply #485 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...
To everyone: before posting in a melting season topic, please be sure to know contents of this moderator's post: https://forum.arctic-sea-ice.net/index.php/topic,3017.msg261893.html#msg261893 . Thanks!

blumenkraft

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Re: The 2020 melting season
« Reply #486 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.

gerontocrat

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Re: The 2020 melting season
« Reply #487 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.
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blumenkraft

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Re: The 2020 melting season
« Reply #488 on: April 27, 2020, 11:35:48 AM »
Yeah, that too i'm afraid.  :-\

F.Tnioli

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Re: The 2020 melting season
« Reply #489 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>
« Last Edit: April 27, 2020, 02:12:42 PM by oren »
To everyone: before posting in a melting season topic, please be sure to know contents of this moderator's post: https://forum.arctic-sea-ice.net/index.php/topic,3017.msg261893.html#msg261893 . Thanks!

Niall Dollard

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Re: The 2020 melting season
« Reply #490 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

ajouis

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Re: The 2020 melting season
« Reply #491 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?
After a thousand steps on the ice, it cracked.
The Man looked down at the infinite blue of the sea.
On the horizon, standing still, the polar bear had just scented his next meal.

 Less than 3000 cubic kilometers this Piomas minimum.

pearscot

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Re: The 2020 melting season
« Reply #492 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.

pls!

grixm

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Re: The 2020 melting season
« Reply #493 on: April 27, 2020, 07:39:25 PM »
According to Nico Sun's area calculations, we are back in spot #1 today.


Freegrass

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Re: The 2020 melting season
« Reply #494 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...
If every 8 year old in the world is taught meditation, we will eliminate violence from the world within one generation.

Phoenix

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Re: The 2020 melting season
« Reply #495 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.

bbr2315

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Re: The 2020 melting season
« Reply #496 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.

Shared Humanity

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Re: The 2020 melting season
« Reply #497 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.

ajouis

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Re: The 2020 melting season
« Reply #498 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
« Last Edit: April 28, 2020, 05:00:57 AM by ajouis »
After a thousand steps on the ice, it cracked.
The Man looked down at the infinite blue of the sea.
On the horizon, standing still, the polar bear had just scented his next meal.

 Less than 3000 cubic kilometers this Piomas minimum.

Paul

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Re: The 2020 melting season
« Reply #499 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.