Arctic Sea Ice Discussion 2015: The Melt Season

[stewfox]

Slow melt season??????? Have you even cared to notice the wholesale destruction of thickness across Beaufort over the past few days? With the Alaskan current delivering waters directly from 'The Blob' , through Bering, it doesn't look good for that side of the basin and into CAB. Aug PIOMAS Figures will be the ones to watch.

 

And a hint for KL, ice melts without disappearing........ it's only when the last bit melts that it disappears.......... Doh!!!

There was a poor winter across Beaufort so I wouldn't expect that area to be holding up well.

 

What we are seeing at present is a more resilient pack (due to volume multi year ice thickness etc). I am not comparing it to 1980's of course but I think the next two weeks will be telling.. Its perfectly plausible to not hit sub 8 m till 20/7 ish and that's allowing for some accelerated loss.IF and its a big if we do then something like a min of 5.8 could be on the cards if we had a average August up there

 

 

https://ads.nipr.ac.jp/vishop/vishop-extent.html?N

[Geordiesnow]

There was a poor winter across Beaufort so I wouldn't expect that area to be holding up well.

 

What we are seeing at present is a more resilient pack (due to volume multi year ice thickness etc). I am not comparing it to 1980's of course but I think the next two weeks will be telling.. Its perfectly plausible to not hit sub 8 m till 20/7 ish and that's allowing for some accelerated loss.IF and its a big if we do then something like a min of 5.8 could be on the cards if we had a average August up there

 

 

https://ads.nipr.ac.jp/vishop/vishop-extent.html?N

 

Heatwave in Siberia/Chuckchi sea aside, the weather conditions have been better for the sea ice in recent times but the ECM has now continually forecast for a strong high to develop and the potential for quite a deep low on the Atlantic side of the Arctic. Admittedly this prediction has largely remained in the 144 hour range but there is perhaps some hints its getting into the more reliable timeframe now. Its one too watch for sure.

[Gray-Wolf]

I think folk had also better be mindful that a good portion of the ice in the basin has been through a few melt cycles.

 

This means some of the ice is bound to be 'rotten ice' and so a Swiss cheese of older ice infilled with FY ice. Piomas/Cryosat just see this as volume and not its integrity under melt pressures.

 

Should the season continue as is then we should see a crash in older ice areas over Aug as the 'carcass' ice succumbs after the FY infill melts out over June/July?

[keithlucky]

Arctic sea ice 750,000 sq km above 2010 only 300.000 sq km from one standard deviation

[keithlucky]

Masie seems the the most accurate of all sea ice measurments, interesting read https://rclutz.wordpress.com/2015/06/28/arctic-ice-extent-leads-2014-june-27/

Edited June 28, 2015 by keithlucky

[Interitus]

Arctic sea ice 750,000 sq km above 2010 only 300.000 sq km from one standard deviation

 

The extent has been looking increasingly rosy throughout June, but the area has been falling at a faster rate. When the extent was at the record low a few weeks ago the compactness of ice described by the ratio area/extent was high but is now decreasing markedly, make no mistake the ice is melting in situ and there also has been little consistent wind which typically sweeps areas of ice leaving clear water.

[oldsnowywizard]

850temps over Barrow at the moment are around+5...where as the actual temp at ground level is +12 ...the forecast of 850s is set to increase to +10 to +15....however the ground temps are forecast to drop to +9 and then further to +4.. im using wetterzentrale and then barrow weather forecast on accuweather... either can be wrong i guess ..but interesting none the less as you would have expected warmer ground temps with an increase in 850s....right?

[knocker]

850temps over Barrow at the moment are around+5...where as the actual temp at ground level is +12 ...the forecast of 850s is set to increase to +10 to +15....however the ground temps are forecast to drop to +9 and then further to +4.. im using wetterzentrale and then barrow weather forecast on accuweather... either can be wrong i guess ..but interesting none the less as you would have expected warmer ground temps with an increase in 850s....right?

 

Not necessarily. 850 temps are a very unreliable guide to surface temps unless you familiar with the airmass structure. Possible low level CAA in your second example or a large inversion if the structure had changed. Assuming those figures are correct and I've no reason to doubt them. Well...............

 

Actually the 850 temp at the moment is -2C and the surface +2C

Edited June 28, 2015 by knocker

[oldsnowywizard]

Proves my point ...alot focus on the wetter charts as gospel... if you look at the 2m charts for barrow they read as 20+ degrees ..no wonder there are comments about extreme warmth... put it into context barrow rarely gets above 15 degrees in summer...not exactly warm... it would be helpful to use some of the towns around the arctic to gain some kind of more accurate reflection of what is going on at the coasts. Cheers knocks!

[knocker]

Actually it doesn't prove your point osw. Your forgetting diurnal variation for example the 12z and 00z soundings (remember these are in GMt not local time and the latest two charts. They are all compatible. You have to compare like with like.

http://www.tropicaltidbits.com/

Edited June 29, 2015 by knocker

[keithlucky]

Arctic sea ice 750,000 sq km above 2010 only 300.000 sq km from one standard deviation

Arctic sea ice 200.000sqkm from one standard deviation 900,000sqkm above 2010

[Geordiesnow]

However 850 temps are read and how that reflects the ground temps, there is now a definate trend the first week of July could be a major change from the fairly cool June, I do feel those on Nevan's forum do like to exagerate as they are eagar for the Arctic to completely melt but you can't deny the weather set ups for later on this week could potentially cause a lot of damage and melting to the ice on the Pacfic side of the Arctic.

 

It does look like this set up will happen in some capacity now after the ECM has hinted this a while back but never came towards the short term however it is now in the 96 hours range and there is firm support from the other models. The obvious question will be, how long will these very warm southerlies into the Pacific last for and how will this affect the SST's in what is an already Chuckchi sea. 

 

Conversely the Atlantic side of the Arctic looks rather cold but unfortunately the cold air is over the more open waters of the Beaufort and Kara Seas rather than say the North Pole itself. 

 

Coupled with the Baffin and Hudson Bay are due to melt(although with the latter, it may still be a short while as conditions still look fairly cool and cloudy here for a while) then we could see some quite large drops during the early part of July. 

[oldsnowywizard]

Actually it doesn't prove your point osw. Your forgetting diurnal variation for example the 12z and 00z soundings (remember these are in GMt not local time and the latest two charts. They are all compatible. You have to compare like with like.

http://www.tropicaltidbits.com/

 

Not really.. i was looking at the high temps... besides even the graphics you provide show Barrow in the green 50f zone... yes there are some warmer temps along the coast a little further along I can see some 20 degrees there but for some reason I like using Barrow to compare... a bit like when others use single points to justify their objective - controversial comment

 

weather.com - http://www.weather.com/weather/tenday/l/Barrow+AK+99723:4:US - highs of 55F or 15C and that is today... going down hill from now on... 

accuweather - http://www.accuweather.com/en/us/barrow-ak/99723/daily-weather-forecast/331720 - 

 

of note is the 850s forecast on the 5th July ie Sunday... I can see a pocket of +10 to +15 850 air... and according to the 2m temps on wetter implying temps of +25... if you compare the links above and any other forecast the high is set to be 49 or 50F or 10 degrees C... so again a point to be made about relying on GFS 2m temps... 

 

anyway.. some interesting charts for you all.. day charts... not bad considering... will they change ? of course... but this is nearly July...

 

 

[Interitus]

of note is the 850s forecast on the 5th July ie Sunday... I can see a pocket of +10 to +15 850 air... and according to the 2m temps on wetter implying temps of +25... if you compare the links above and any other forecast the high is set to be 49 or 50F or 10 degrees C... so again a point to be made about relying on GFS 2m temps...

But 850mb temps of 10-15°C do not imply a surface temperature of 25°C, though that may be wrongly inferred...as Knocker pointed out temperature inversions persist throughout the summer (indeed most of the year) over the Arctic ocean which buffers the ice from influxes of warm air to a large degree, and also keeping coastal locations cooler than inland. The GFS 2m temperatures quite accurately reflect this. The GFS 3d-globe on Meteociel is excellent for looking at individual locations and gives forecast tephigrams and temperatures at various levels. Right-click on a chosen point to see the various options - try 'Prévisions GFS - mode Neige avancé' which gives temperatures at 2m, 975mb, 950mb, 925mb, 900mb and 850mb, the geopotential heights at these levels, precipitation, surface pressure, 1000-500mb thickness and freezing level.

Edited June 29, 2015 by Interitus

[stewfox]

But 850mb temps of 10-15°C do not imply a surface temperature of 25°C, though that may be wrongly inferred...as Knocker pointed out temperature inversions persist throughout the summer (indeed most of the year) over the Arctic ocean which buffers the ice from influxes of warm air to a large degree, and also keeping coastal locations cooler than inland. The GFS 2m temperatures quite accurately reflect this. The GFS 3d-globe on Meteociel is excellent for looking at individual locations and gives forecast tephigrams and temperatures at various levels. Right-click on a chosen point to see the various options - try 'Prévisions GFS - mode Neige avancé' which gives temperatures at 2m, 975mb, 950mb, 925mb, 900mb and 850mb, the geopotential heights at these levels, precipitation, surface pressure, 1000-500mb thickness and freezing level.

 

Have a block of ice larger then the USA and you will find 2m temps have little correlation with 850mb.

 

Its why the 2m temps in high artic vary little in the summer , you don't get 15c (as average) or even 5c or 2c  up there ever

[Interitus]

Have a block of ice larger then the USA and you will find 2m temps have little correlation with 850mb.

 

Its why the 2m temps in high artic vary little in the summer , you don't get 15c (as average) or even 5c or 2c  up there ever

Of course the ice plays an important role in its own preservation, the latent heat of melting and the radiative surface creates the inversions. Cold water bodies act similarly to an extent, you don't get a 15°C average in the Shetlands for example. Mind you note that Alert in Canada north of 82° on the coast of the Central Arctic Basin and the northernmost permanently inhabited place reached 14.7°C today.

Edited June 29, 2015 by Interitus

[Geordiesnow]

What about 850 temps over open water in the Arctic ocean, surely upper air temps of those intensity will warm the open water areas even more therefore melting from underneath the ice will then occur. Then you got the unfavorable wind direction and the strength of the wind also which should start pushing the ice away from the coast. 

 

still, looking at the upcoming set ups, they do look quite concerning and there is the potential for quite a sharp drop in extent as we head into the first 7-10 days in July. 

[stewfox]

 

still, looking at the upcoming set ups, they do look quite concerning and there is the potential for quite a sharp drop in extent as we head into the first 7-10 days in July. 

 

Its pleasing that we haven't seen any 100k drops in recent weeks. Clearly as we enter what is often the biggest melt period we will start to see 100k plus drops. 

[Gray-Wolf]

We had a 100k + plus drop on June 28th?

[Geordiesnow]

Its pleasing that we haven't seen any 100k drops in recent weeks. Clearly as we enter what is often the biggest melt period we will start to see 100k plus drops. 

 

Coupled with the ominous weather patterns then I suppose things in terms of extent could be worse but I don't think I've seen a year where potentially we could see an awful lot of hot air over the high latitudes. Obviously that heat may not come off but the GFS run shows the 20C really widespread across Russia. 

 

The heat dome across Chuckchi is nailed on, but how much heat will enter the Laptev is still open to doubt and now the models are hinting at unfavourable wind direction and heat coming into Beaufort Sea so all in all, on paper, July is starting with testing conditions for the sea ice.  

[stewfox]

Coupled with the ominous weather patterns then I suppose things in terms of extent could be worse but I don't think I've seen a year where potentially we could see an awful lot of hot air over the high latitudes. Obviously that heat may not come off but the GFS run shows the 20C really widespread across Russia. 

 

 

What has that got to do with Arctic ? Even northern Siberia can often see 90F + this time of year with 24hr sun

 

500,000 now above 2012 cf 500,000 below on  6 June

 

Yesterdays 50k drop was the smallest for the start of July since 2005.

 

DMI temps remain average just above freezing

 

http://ocean.dmi.dk/arctic/meant80n.uk.php

[Geordiesnow]

What has that got to do with Arctic ? Even northern Siberia can often see 90F + this time of year with 24hr sun

 

500,000 now above 2012 cf 500,000 below on  6 June

 

Yesterdays 50k drop was the smallest for the start of July since 2005.

 

DMI temps remain average just above freezing

 

http://ocean.dmi.dk/arctic/meant80n.uk.php

 

Because of the close proximity to the Arctic , it is very unusual on that widespread scale, this afternoon runs has somewhat scaled back on that and its quite far off anyways. 

 

However what seems to be getting more certain is not only the heat that will hit the Chuckchi sea area but we will see the high pressure cell moving from there to Beaufort which will promote winds from the hot landmass and the likelyhood of clearer skies also. With extent remaining higher than in recent years in Hudson and Baffin, then the potential for quite a sharp drop in extent is there.

[stewfox]

Because of the close proximity to the Arctic , it is very unusual on that widespread scale, this afternoon runs has somewhat scaled back on that and its quite far off anyways. 

 

However what seems to be getting more certain is not only the heat that will hit the Chuckchi sea area but we will see the high pressure cell moving from there to Beaufort which will promote winds from the hot landmass and the likelyhood of clearer skies also. With extent remaining higher than in recent years in Hudson and Baffin, then the potential for quite a sharp drop in extent is there.

 

Can you post some evidence , e.g as I have posted before Hudson looks like very average (ice remaining) 

 

Another small drop today.

[keithlucky]

Arctic ice within 82,000sq km,of one standard deviation tied with 2005 this day ,Arctic sea ice similar to 2005 levels Piomas shows sea ice thickness is high toohttp://psc.apl.uw.edu/wordpress/wp-content/uploads/schweiger/ice_volume/Bpiomas_plot_daily_heff.2sst.png

Edited July 3, 2015 by keithlucky

[stewfox]

Arctic ice within 82,000sq km,of one standard deviation tied with 2005 this day ,Arctic sea ice similar to 2005 levels Piomas shows sea ice thickness is high toohttp://psc.apl.uw.edu/wordpress/wp-content/uploads/schweiger/ice_volume/Bpiomas_plot_daily_heff.2sst.png

 

 

 

I see another sub 60k drop today, at this rate we will be back to 1980s soon  

 

Seriously if you look at the ice thickness now cf 2012 you can see how much more of the 2m/3m ice there is.

 

Usual spots with 4/5m thickness are similar and of course most of the sub 2m will met out but you left with a much larger core.

 

However whats remaining in Hudson will go fairly soon (3 weeks) but i cant see sub 8m  in the next 2 weeks and given the winter we had that will be remarkable.

 

Still much of the summer to go of course but I'm sure most folk will agree we wont get a 'record this year' unless its for recovery.

Edited July 4, 2015 by stewfox