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epiphyte

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Re: The 2019 melting season
« Reply #1250 on: May 28, 2019, 06:43:03 PM »
According to GPS, we now have a setup with high pressure AND above average freezing temp right at the north pole. The size of the above average temp ring isn't massive. Maybe it's covering 20% of the ocean.

 ...Which is to say, about a million square miles, or 4x the size of Texas. Not so big at all :)

oren

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Re: The 2019 melting season
« Reply #1251 on: May 28, 2019, 06:47:18 PM »
An animated comparison with 2016 from Wipneus' "Home Brew AMSR2" thread:
Thank you Jim for bring this to a wider audience.
While 2019 tops 2016 in extent, the main difference visible here is the large amount of ice in the Barents and the CAB's Svalbard sector, which was missing in 2016. So the higher extent should not lull anyone into a false sense of complacency. Should June and July be more sunny in the high arctic, this year could easily end up lower than 2016, which had a very cloudy summer weather and despite this managed to threaten 2012's record low (admittedly helped by its own August GAC).

be cause

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Re: The 2019 melting season
« Reply #1252 on: May 28, 2019, 07:08:48 PM »
Looks like water is arriving in the Lena delta .. and quite a lake has built up just inland . The snow melt in the area continues to be impressive .. b.c.
2007 + 5 = 2012 + 4 = 2016 + 3 = 2019 + 2 = 2021 
 (phew)

b_lumenkraft

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Re: The 2019 melting season
« Reply #1253 on: May 28, 2019, 07:19:35 PM »
Kara sea ice degradation in recent days.

The ice is still there, and will not really show in the numbers tomorrow. Still, this ice is already walking dead.

Jim Hunt

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Re: The 2019 melting season
« Reply #1254 on: May 28, 2019, 08:06:14 PM »
Looks like water is arriving in the Lena delta .. and quite a lake has built up just inland .

Do you have an image you can share? A Worldview link perhaps? I watch eagerly for this every year, and I'm blowed if I can see anything there this year as yet. Here's one I prepared earlier, from June 1st 2016:

http://GreatWhiteCon.info/resources/arctic-sea-ice-images/summer-2016-images/#Laptev

I reckon it'll be difficult to beat that this year.
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

be cause

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Re: The 2019 melting season
« Reply #1255 on: May 28, 2019, 09:04:32 PM »
  sorry Jim .. I have no idea how to share images .. but it is to the west of the main delta that I see water filling channels .. clearer yesterday .. @ 72.42N 126.30E ..

 My post was intended to be an advanced warning .. I expect the delta open in the next 48-73 hours ..

  Last year I reported the delta open on May 31 .. I first observed flow leaving the delta on the 29th .. earlier than 2016 .
  Your blue version of Worldview shows things best perhaps .. b.c.
2007 + 5 = 2012 + 4 = 2016 + 3 = 2019 + 2 = 2021 
 (phew)

Jim Hunt

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Re: The 2019 melting season
« Reply #1256 on: May 28, 2019, 09:34:00 PM »
clearer yesterday .. @ 72.42N 126.30E

Thanks - I'm with you now: https://go.nasa.gov/2Maln2W

I still reckon we'll be hard pressed to beat 2016 though!
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Rod

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Re: The 2019 melting season
« Reply #1257 on: May 28, 2019, 10:11:56 PM »
The ICESat2 data is now available!

I have no idea how to get it or how to use it, but it could make this melt season very interesting if it turns out to be user friendly. 

I can't get the links to Twitter to work from my phone, but it should be pretty easy to locate with a search. 
« Last Edit: May 28, 2019, 10:22:18 PM by Rod »

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Re: The 2019 melting season
« Reply #1258 on: May 28, 2019, 11:04:38 PM »
The ICESat2 data is now available!

It is indeed: https://nsidc.org/data/icesat-2/products/level-3b

As far as I can tell the nearest thing to what we are after is the level 3B Gridded Monthly Sea Ice Freeboard (ATL20). However a quick scan of the site has yet to reveal a product that converts those numbers into sea ice thickness.
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Rod

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Re: The 2019 melting season
« Reply #1259 on: May 28, 2019, 11:21:41 PM »
It looks like ATL07 and ATL10 might be necessary to answer that question Jim.  Unfortunately, this product seems very advanced for amateurs.  As far as I can tell, you need to write a script just to go in and retrieve the data you want to review. 

I seem to recall you have a programming background (I might be wrong but I think I remember reading that somewhere)  Maybe you and Wipneus can figure it out?

It appears to be a very powerful tool.  I just hope it is something that we don't have to wait for peer reviewed publications before we can see the data. 

EDIT- I just saw they answered the question you asked on Twitter, and not all data products have been released yet.  I guess that is good news.  Maybe things won't look so difficult to use once all of the data products have been released.  🤔
« Last Edit: May 28, 2019, 11:57:17 PM by Rod »

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Re: The 2019 melting season
« Reply #1260 on: May 29, 2019, 12:11:08 AM »
I just saw they answered the question you asked on Twitter, and not all data products have been released yet.  I guess that is good news.  Maybe things won't look so difficult to use once all of the data products have been released.  🤔

The NSIDC informed me that:

Quote
Not all of the ICESat-2 data has been released - these are just the first available data sets. Keep a look out for the Level-3B products, which are the gridded products. They will be released in the future, but we don’t yet have a release date.
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

Jim Hunt

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Re: The 2019 melting season
« Reply #1261 on: May 29, 2019, 12:44:15 AM »
I seem to recall you have a programming background (I might be wrong but I think I remember reading that somewhere)  Maybe you and Wipneus can figure it out?

You are not wrong! I learnt to program computers at school in the days when there were no computers in schools. We built our own.

I've asked the NSIDC some pertinent questions, but they haven't got back to me yet. It seems highly unlikely it's a job that "citizen scientists" could do, but if you never ask the question you never discover the answer!
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

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Re: The 2019 melting season
« Reply #1262 on: May 29, 2019, 01:39:37 AM »
According to GPS, we now have a setup with high pressure AND above average freezing temp right at the north pole. The size of the above average temp ring isn't massive. Maybe it's covering 20% of the ocean.

 ...Which is to say, about a million square miles, or 4x the size of Texas. Not so big at all :)

I guess that would make the area that is near or below freezing about 16 times the size of Texas.

All relative.

magnamentis

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Re: The 2019 melting season
« Reply #1263 on: May 29, 2019, 04:01:47 AM »
current temps in barrows alaska 12C

no clue where you're all looking, temps are obvious even with the naked eyes.

one image upthread showed a 10 days  forecast but i talk abou this afternoon (local)

use this link to see the webcam as well as the temps if you click the weather link on that page

last but not least windy confirmst the temp range and so does reanalyzer once looking carefully.

my point by the way is who the ice looks when it's melting in serious, not the temps, they are in fact 2C lower than forecasted yesterday.

http://seaice.alaska.edu/gi/observatories/barrow_webcam

petm

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Re: The 2019 melting season
« Reply #1264 on: May 29, 2019, 04:08:08 AM »
everything looks potentially catastrophic except , as Gerontocrat points out , the figures .
IMHO, top line numbers never mean much, particularly extent (unless you fancy a boat ride). Look at the Beaufort for example this year vs. 2016. Extent just increased, but I'd say the prognosis is terrible: huge areas of open water between very few large floes. Frankly it's not even clear to me what matters; we may not know it until we see it. One possibility: is halocine degeneration looming (and if so what conditions might accelerate it) (https://physicsworld.com/a/strength-of-arctic-halocline-indicates-climate-change/).

oren

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Re: The 2019 melting season
« Reply #1265 on: May 29, 2019, 04:35:17 AM »
current temps in barrows alaska 12C

no clue where you're all looking, temps are obvious even with the naked eyes.

one image upthread showed a 10 days  forecast but i talk abou this afternoon (local)

use this link to see the webcam as well as the temps if you click the weather link on that page

last but not least windy confirmst the temp range and so does reanalyzer once looking carefully.

my point by the way is who the ice looks when it's melting in serious, not the temps, they are in fact 2C lower than forecasted yesterday.

http://seaice.alaska.edu/gi/observatories/barrow_webcam
All other weather sites report around 2C for Barrow/Utqiagvik. It seems there is a bug with the Weatherbug website. I believe the reason could be their location for Barrow is further south than the actual location of the town, look at the map on their website, it's off. Temps inland are much higher than right on the coast.

Rod

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Re: The 2019 melting season
« Reply #1266 on: May 29, 2019, 04:36:23 AM »
current temps in barrows alaska 12C

http://seaice.alaska.edu/gi/observatories/barrow_webcam

I don't think current temperatures are anywhere near that hot in Barrow.  That is about where they are running in Anchorage right now.

However, I agree that the fast ice is melting in Barrow and won't be around much longer. 

Retron

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Re: The 2019 melting season
« Reply #1267 on: May 29, 2019, 05:16:38 AM »
current temps in barrows alaska 12C

More like 2C.

https://w1.weather.gov/obhistory/PABR.html

(That's the airport, which is on the south side of the town).

That said, the dewpoint is now above zero (Celcius) and that'll be accellerating the melt.

magnamentis

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Re: The 2019 melting season
« Reply #1268 on: May 29, 2019, 05:34:38 AM »
current temps in barrows alaska 12C

http://seaice.alaska.edu/gi/observatories/barrow_webcam

I don't think current temperatures are anywhere near that hot in Barrow.  That is about where they are running in Anchorage right now.

However, I agree that the fast ice is melting in Barrow and won't be around much longer.

so what click the link, click the weather link and see for yourself

further i checked various other sites like reanalyzer which show temps clearly in the 10C region one has to enlarge the images and look very carefully because about 50-100km out it's below freezing.

but if you wait long enough it will cool down to around 6C in a few hours LOL

Rich

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Re: The 2019 melting season
« Reply #1269 on: May 29, 2019, 07:20:27 AM »
current temps in barrows alaska 12C

http://seaice.alaska.edu/gi/observatories/barrow_webcam

I don't think current temperatures are anywhere near that hot in Barrow.  That is about where they are running in Anchorage right now.

However, I agree that the fast ice is melting in Barrow and won't be around much longer.

so what click the link, click the weather link and see for yourself

further i checked various other sites like reanalyzer which show temps clearly in the 10C region one has to enlarge the images and look very carefully because about 50-100km out it's below freezing.

but if you wait long enough it will cool down to around 6C in a few hours LOL

With all due respect, you've wandered into a bad data source. It's not hitting 12c in Barrow (Utqiagvik).


binntho

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Re: The 2019 melting season
« Reply #1270 on: May 29, 2019, 08:14:03 AM »

so what click the link, click the weather link and see for yourself

further i checked various other sites like reanalyzer which show temps clearly in the 10C region one has to enlarge the images and look very carefully because about 50-100km out it's below freezing.

but if you wait long enough it will cool down to around 6C in a few hours LOL

Just now the link shows 10C, but ALL OTHER sources show 1 between 1 and 2 degrees. So I don't know what "various other sites" other than reanalyzer you have checked. But even climatereanalyzer.com has northern Alaska firmly in the green colors signifying temperatures around 0 and nowhere near 10.
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Jim Hunt

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Re: The 2019 melting season
« Reply #1271 on: May 29, 2019, 10:27:39 AM »
current temps in barrows alaska 12C

no clue where you're all looking, temps are obvious even with the naked eyes.

I have no clue where you're looking, but here's the official NWS forecast for "Barrow, Wiley Post-Will Rogers Memorial Airport (PABR)"

https://forecast.weather.gov/MapClick.php?lat=71.290575&lon=-156.788716327

Meanwhile here's the official UKMO forecast for "Barrow in Furness (Cumbria)"

https://www.metoffice.gov.uk/weather/forecast/gcteyf1nd

Shall we play "spot the difference"?
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oren

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Re: The 2019 melting season
« Reply #1272 on: May 29, 2019, 11:27:31 AM »
I repeat:
It seems there is a bug with Weatherbug (the site linked from the Barrow webcam page). I believe the reason is that their location for Barrow is further south than the actual location of the town, look at the map on their website, it's off. Temps inland are much higher than right on the coast.

max_123

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Re: The 2019 melting season
« Reply #1273 on: May 29, 2019, 11:35:51 AM »
Hi everyone
first time poster and attentive reader of the forum  :)

Maybe that helps dissolve some of the confussion about the weather in barrow:
https://www.meteoblue.com/en/weather/forecast/multimodel/barrow_united-states-of-america_5880054

F.Tnioli

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Re: The 2019 melting season
« Reply #1274 on: May 29, 2019, 12:29:46 PM »
IMHO, top line numbers never mean much, particularly extent (unless you fancy a boat ride). ...
Very true. Can we have this line (possibly minus "IMHO" part) carved into stone-like background and put somewhere in or near ASIF header picture, please? I'm serious. So great many people overvalue "totals" it ain't no funny at all. You know.

Added: about Barrow - i see open water is present on shore land (ponds are not covered with any bit of ice), means it's above freezing:

And tomorrow, 10+ km visibility in Barrow forecasted all 24 hours, i noticed. Much sun, of course. "Ouch". Large area of open water on horizon is visible on the left side of the picture. Dark land, dark water, plenty low albedo, and much sun. Guess this ice is walking dead, too.
« Last Edit: May 29, 2019, 01:10:12 PM by F.Tnioli »
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!

Jim Hunt

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Re: The 2019 melting season
« Reply #1275 on: May 29, 2019, 01:01:52 PM »
Hi everyone
first time poster and attentive reader of the forum  :)

Welcome Max, and thanks very much for the heads up!

MeteoBlue has somehow avoided my radar screen up to now. A small sample:

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b_lumenkraft

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Re: The 2019 melting season
« Reply #1276 on: May 29, 2019, 01:06:03 PM »
Hi everyone

Hello and welcome to the forum Max. :)

MA Rodger

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Re: The 2019 melting season
« Reply #1277 on: May 29, 2019, 01:55:36 PM »
The Barrow AK temperature mystery comes from the weatherbug website (1st link below) which was mentioned upthread as a "weather" link from the webcam page (2nd link below).

https://www.weatherbug.com/weather-forecast/now/barrow-ak-99791
https://seaice.alaska.edu/gi/observatories/barrow_webcam/

The mystery arises when the weatherbug page is reset from Fahrenheit to Celsius (button on the top tool bar). Odd things happen unless the page is refreshed.

petm

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Re: The 2019 melting season
« Reply #1278 on: May 29, 2019, 02:14:56 PM »
Quote
Not all of the ICESat-2 data has been released - these are just the first available data sets. Keep a look out for the Level-3B products, which are the gridded products. They will be released in the future, but we don’t yet have a release date.

Can't wait to see this used for volume!

Jim Hunt

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Re: The 2019 melting season
« Reply #1279 on: May 29, 2019, 02:17:49 PM »
The Barrow AK temperature mystery ... arises when the weatherbug page is reset from Fahrenheit to Celsius (button on the top tool bar). Odd things happen unless the page is refreshed.

Thanks Al,

Hopefully we can all now get back to the extremely interesting 2019 melting season!
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petm

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Re: The 2019 melting season
« Reply #1281 on: May 29, 2019, 02:39:31 PM »
IMHO, top line numbers never mean much, particularly extent (unless you fancy a boat ride). ...
Very true. Can we have this line (possibly minus "IMHO" part) carved into stone-like background and put somewhere in or near ASIF header picture, please? I'm serious. So great many people overvalue "totals" it ain't no funny at all. You know.
Good, I needed a signature.  ;)

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Re: The 2019 melting season
« Reply #1282 on: May 29, 2019, 04:05:21 PM »
Thick ice possibly in another step of decline just off Banks & Queen Elizabeth Islands area. Additionally Beaufort joining the Chucki sea shortly with open water according to nrlssc.navy forecast.

https://www7320.nrlssc.navy.mil/GLBhycomcice1-12/navo/beaufortictn_nowcast_anim30d.gif


b_lumenkraft

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Re: The 2019 melting season
« Reply #1283 on: May 29, 2019, 04:21:24 PM »
Gnihihi, notice how this model is totally forgetting it predicted 5m ice when it cracked...

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Re: The 2019 melting season
« Reply #1284 on: May 29, 2019, 04:38:30 PM »
Hi Folks,

As we have discussed before about the influence of the jetstream on weather patterns and melting, there is also a link in the other direction and there's now a way to model it.
Article here:
https://phys.org/news/2019-05-arctic-weather-extremes-latitudes.html

And paper here:
https://www.nature.com/articles/s41598-019-43823-1

In summary - more loops in the jetstream are to be expected as warming reduces the temperature differential driving the jetstream leading to more mid latitude extreme weather / blocking patterns.


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Re: The 2019 melting season
« Reply #1285 on: May 29, 2019, 04:43:53 PM »
Gnihihi, notice how this model is totally forgetting it predicted 5m ice when it cracked...

I agree for some reason this model has huge and unrealistic fluctuations regarding sea ice thickness. However it may point out areas of interest to reflect on further in the season as melt gathers pace or winds change direction.

b_lumenkraft

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Re: The 2019 melting season
« Reply #1286 on: May 29, 2019, 04:50:49 PM »
Agreed James. Thanks for sharing.

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Re: The 2019 melting season
« Reply #1287 on: May 29, 2019, 05:08:15 PM »
Hi Folks,

Article here:
https://phys.org/news/2019-05-arctic-weather-extremes-latitudes.html
And paper here:
https://www.nature.com/articles/s41598-019-43823-1

In summary - more loops in the jetstream are to be expected as warming reduces the temperature differential driving the jetstream leading to more mid latitude extreme weather / blocking patterns.
loops in the jetstream = Rossby Waves

I wonder if any of these articles pay tribute to - Carl-Gustaf Arvid Rossby
"If I have seen further it is by standing on the shoulders of Giants" - Isaac Newton

https://www.britannica.com/biography/Carl-Gustaf-Arvid-Rossby
Quote
Carl-Gustaf Arvid Rossby, (born Dec. 28, 1898, Stockholm, Swed.—died Aug. 19, 1957, Stockholm), Swedish American meteorologist whose innovations in the study of large-scale air movement and introduction of the equations describing atmospheric motion were largely responsible for the rapid development of meteorology as a science.

In his studies he identified sinusoidal waves, now known as Rossby waves, in the polar jet stream. He also developed the theory of Rossby wave movement. He worked on mathematical models for weather prediction and introduced the Rossby equations, which were used in 1950 with an advanced electronic computer to forecast the weather.
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Re: The 2019 melting season
« Reply #1288 on: May 29, 2019, 06:03:23 PM »
As many of you here know, for an excellent source of approachable information on Rossby Waves and the jetstream, do a Youtube or Google search for Jennifer Francis.

She has a number of talks and interviews at various technical levels.

Over the (hopefully) longer term, the effects of a reduced temperature differential between the poles and mid latitudes can not be underestimated. 

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Re: The 2019 melting season
« Reply #1289 on: May 29, 2019, 07:02:52 PM »
Directed over there from Judith Curry's blog, I've just had a brief discussion with Judah Cohen on Twitter about his latest forecast for the Northern Hemisphere. Clearly great minds think alike!

https://twitter.com/GreatWhiteCon/status/1133776436702134272

Quote
If polar cap geopotential height anomalies remain on the warm/positive side for much of the summer, this could result in accelerated sea ice loss relative to recent summers.
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

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Re: The 2019 melting season
« Reply #1290 on: May 29, 2019, 09:28:36 PM »
Directed over there from Judith Curry's blog, I've just had a brief discussion with Judah Cohen on Twitter about his latest forecast for the Northern Hemisphere. Clearly great minds think alike!

https://twitter.com/GreatWhiteCon/status/1133776436702134272

Quote
If polar cap geopotential height anomalies remain on the warm/positive side for much of the summer, this could result in accelerated sea ice loss relative to recent summers.

Thanks for the blog link, Jim.

I'm struck by what appears to be a decent increase in ice volume overall from 2012 and 2016 at this date. Does there exist an end of season type summary that shows overall sea ice volume growth? I know Judith's post says the CryoSat-2 tries to measure ice thickness. How accurate is it?

I'm a long time lurker here but my memory must be poor. I don't recall the previous years ending with an increase in MYI. Am I wrong on that? Was 2017-2018 that good for ice in the CAA?

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Re: The 2019 melting season
« Reply #1291 on: May 29, 2019, 09:44:08 PM »
Yeah, the measurements of volume don't make much sense to me, given that MYI is at record lows, and extent is second lowest.

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Re: The 2019 melting season
« Reply #1292 on: May 29, 2019, 10:25:55 PM »
Second try. The forum software decided I had typed enough and "auto-posted" me.
-----
I'm going to stick my neck out here and say that there is a temptation to correlate thickness with age, when no such correlation exists. I think that assumption used to be valid, but the ice is now much thinner, weaker and mobile.

As such, is it very susceptible to bunching, ridging and just generally piling up, particularly along the CAA.

Because the ice is much more fragmented now at this time, it looks like the thickness is an indication of ice movement seen in the past, but much later in the season.

For example, if you look at the increased thickness on the AO side of Fram Strait, it looks like everybody is crowding in line, waiting for their express ride down to Newfoundland.

Of course that could all be dead wrong. It's been known to happen before... 

be cause

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Re: The 2019 melting season
« Reply #1293 on: May 29, 2019, 11:10:08 PM »
   If you can .. take a look at what has happened @ 69.40N 170.40E over the last week . Especially dramatic is the blue on Worldview that Jim Hunt uses to see the melt ponds .
   It looks like the Ice Queen losing posession of Narnia !  Summer arrives (out of the blue) .
 
   The sea ice off shore is just melting out in situ , almost as if it has been set on fire . I suppose this could be described as a ' melt whole ' :)  . May in the Siberian Arctic ! .. b.c.

ps .. nearly forgot .. the forecasts suggest that this is a small taste of what may come , but what @ that strange little cold low that's heading across the anticyclone toward Siberia ? Any thoughts ?
« Last Edit: May 30, 2019, 12:38:27 AM by be cause »
2007 + 5 = 2012 + 4 = 2016 + 3 = 2019 + 2 = 2021 
 (phew)

El Cid

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Re: The 2019 melting season
« Reply #1294 on: May 29, 2019, 11:44:22 PM »
I'm not goin' Friv 21 again :) but the latest ECMWF forecast still looks pretty damn serious: No end in sight for solar bombardment on the Pacific side/N. Pole (and it stay s that way up until T+10 days)

petm

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Re: The 2019 melting season
« Reply #1295 on: May 30, 2019, 12:17:38 AM »
loops in the jetstream = Rossby Waves

I wonder if any of these articles pay tribute to - Carl-Gustaf Arvid Rossby

Yes, nearly 1200 Google Scholar citations:
https://scholar.google.com/scholar?https://scholar.google.com/scholar?hl=en&as_sdt=5,33&sciodt=0,33&cites=12484635752749492230&scipsc=

Paul

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Re: The 2019 melting season
« Reply #1296 on: May 30, 2019, 12:23:55 AM »
Again I think there is a classic case of looking at a chart and immediately thinking because it's high pressure its going to be wall to wall blue skies and sunshine where in fact there is small troughs and marginally lower thicknesses circulating the high therefore I imagine there be more cloud cover than you may think. I could be wrong on the cloud cover but it how I see it. Also because the high is forecast to remain in situ over the Arctic, it is not as yet drawing in too much warm air from the continents either and the air under the high is fairly chilly.

No doubt there will be some sunny skies also though and given what we seen so far, the ice does look quite vunable in the Beaufort and the winds are forecast to be fairly strong but not to the scale we seen during this month.

Jim Hunt

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Re: The 2019 melting season
« Reply #1297 on: May 30, 2019, 12:28:06 AM »
   If you can .. take a look at what has happened @ 69.40N 170.40E over the last week . Especially dramatic is the blue on Worldview that Jim Hunt uses to see the melt holes .

Near Pevek? https://go.nasa.gov/2MgPJ3Y

Do the helpful hints make sense?
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

Jim Hunt

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Re: The 2019 melting season
« Reply #1298 on: May 30, 2019, 01:04:46 AM »
I'm struck by what appears to be a decent increase in ice volume overall from 2012 and 2016 at this date. Does there exist an end of season type summary that shows overall sea ice volume growth?

PIOMAS?

https://forum.arctic-sea-ice.net/index.php/topic,119.msg197804.html#msg197804

The slow transition thread? Here's an extract:

https://forum.arctic-sea-ice.net/index.php/topic,2709.msg201630.html#msg201630

Quote
I know Judith's post says the CryoSat-2 tries to measure ice thickness. How accurate is it?

You left out the "uncertainty" plot from my previous post! Not perfect by any means. Once the satellite has worked out the "freeboard" it has to make assumptions about snow density and thickness to work out the ice thickness.

https://www.sciencedirect.com/science/article/pii/S0273117717306403

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I'm a long time lurker here but my memory must be poor. I don't recall the previous years ending with an increase in MYI. Am I wrong on that? Was 2017-2018 that good for ice in the CAA?

Beginning in 2016 lots of the "oldest thickest ice in the Arctic" started meandering out of the Basin and out through the "garlic press" of the CAA. It chased brave little Northabout all the way to Baffin Bay for example!

http://GreatWhiteCon.info/2016/08/northabout-braves-the-northwest-passage/
« Last Edit: May 30, 2019, 01:24:29 AM by Jim Hunt »
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

GoSouthYoungins

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Re: The 2019 melting season
« Reply #1299 on: May 30, 2019, 03:06:51 AM »
WOW, 20 km west move in the coastal Beaufort in 24 hrs. I thought there was some fast and strongish ice between the Beaufort and the Chukchi seas. But apparently the whole area is slush. June will be harsh.
big time oops