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One of the distinctive features of the 2012 season was a clear Greenland high/-ve NAO, extending slightly into the central Arctic basin. This pulled some very warm air up through the Canadian Archipelago and in across the Arctic Ocean.

.............................SLP Anomaly................................... Vector Wind Anomalies..................925hPa Air Temperature Anomalies

2012_SLPA.thumb.gif.2409ad70c470743e404ff7d5ea33b0b7.gif2012_VWA.thumb.gif.0e1a6aaa94ed49eb3dd6b310de6cf914.gif2012SATA.thumb.gif.ca1ab3608d76dc99bbe51fc46ebb0784.gif

The 2012 June-July-August average NAO was the most -ve on record at -1.61.  In fact, 4 of the 5 most -ve NAO JJA periods since 1950 occurred in the 6 years from 2011 to 2011 (2011, 2012, 2015 and 2016), yet the other years didn't quite match the ice loss of 2012.

.....................SLP Anomaly 2011..................................................2012 ........................................................... 2015 ............................................................. .2016
2011SLPA.thumb.gif.abbed570b109c03bec74be3ef46ce12c.gif2012SLPA.thumb.gif.add12b62ccd769d407139dd7cbb2915a.gif2015SLPA.thumb.gif.03c7bdfad0d739011cd69fd56b149d84.gif2016SLPA.thumb.gif.ffba5919aab7aff076db924d81ba8667.gif

The patterns of the NAO were different in each season, both in terms of the strength during the summer and the spatial distribution of the SLP anomalies. One of the big differences was the pack pre-conditioning during June. In 2012, there was widespread melt ponding in June, during what was the 2nd most -ve NAO on record. This is thought to help sustain fast rates of ice loss throughout the rest of the melt season. Of course, there was then the August storm, GAC 2012, that wiped out a large area of weak ice in August, helping to make the record low a substantial new record, but otherwise, the weather wasn't particularly extreme after June.

While this year has not seen the extreme -ve NAO values (weakly negative since April) the NAO looks like turning very -ve by the weekend, and we have seen widespread melt ponding events, beginning usually early in May, but also occurring in June. This has caused the sea ice modelling team, led by David Schröder at Reading Uni, to predict a September minimum this year of close to that of 2012.
If we manage to have an ice pack pre-conditioned for rapid melt, plus even warmer conditions throughout the remainder of the summer (the extreme heat records in Siberia and record low ice along the Siberian coastline demonstrates the potential for this), it could turn into a very interesting melt season. But Arctic weather tends to make fools of everyone, so best not to make any definitive predictions just yet!

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The anomaly continues to grow, NSIDC extent now 570k below the next lowest year, and below the minima of 1979, 80, 81, 82, 83, 86, 86, 87, 88, 89, 92, 94, 96, 97 and 2001. We're 1 million km^2 below

Your more than welcomed to post on this thread but even if the UK does not always have the heat, sadly elsewhere across the globe most certainly does.  MIA - From what I gathered, you thought the

Using previous 20 years melt rates from August 26th, all produce the 2nd lowest minimum on record. Here's a slow animation from the last few days, highlighting the continued push north of t

Posted Images

I'm a firm believer in both 'melt momentum' and that the ice has a 'point of no return' in any one melt season?

The past decade, to my eyes, has seen a year on year 'conditioning' of the ice for every easier melting.

The evolution of the Atlantification/Pacification of the basin also appears to be a change very difficult to see 'undone'

The 'mixing out' of the unique layering of the Arctic Ocean makes it impossible for me to imagine a return to the ice cover of my youth (60's & 70's?) without disastrous changes to the Earth's climate system in a direct opposite way to the forcings we see today

This said I'm of the opinion that "When the ice goes it will go very quickly....." and this constant 'conditioning' of the pack has made that an event we can now envisage in a way that we could not in our pasts.

A younger pack, a more fragmented pack, a pack with 'faux' aged ice (an old skim with a keel of FY ice below) and ever faster transport coupled with the changes to atmosphere and ocean must surely bring the first ice free year ever closer?

I feel the next month will see many folk with concerns for the ice esp. if we see continued 'torching' of regions and potential di-pole to clear out of the ice sat above Fram

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The ECM 12z of today is perhaps the most Arctic ice-hammering model run I’ve ever witnessed.

It creates strong highs in optimum positions for hammering sea ice volume especially. 

GFS’ version of events is less clean but still a story of unusual high pressure + very anomalous warmth combining over the high Arctic.

We can only hope that the models are overdoing this. Always a good chance of that longevity-wise for things past four days range.

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1avfter 07' , midst the cheering over 'recovery' we saw the collapse and spread of the older ice into the 'Rotten Ice' prof Barber named.

In 2010 (?) we saw the very last of our 'paleocryistic' ice go sp preparing the pack for the kind of drop we witnessed in 2012 ( when conditions arose to suit such losses?)

As I said above the lack of 'record lows' this past 8 years does not mean 'change' was not occurring across the basin?

Now Mother N. seems to be offering up the kind of conditions to help us see what that 'conditioning' has meant to the basin with regard to melt out/export/evolution of 'open water hot spots' inside the basin to melt transported ice.

I'm starting to think I should pay closer attention to the next 2 months of losses/weathers in the basin...... 

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Well we dropped to 2nd lowest on the JAXA plot today and it looks like we will slip to lowest as we move forward and current conditions across the basin begin to bite (incl. Fram export and the high pressure dome camped across the C.A.B.?)

The extreme heat in parts of Siberia looks likely to be drawn over the ice as the H.P. settles in?

When I look at 'ice age' comparisons from 2012 to today it confirms to me that even the ice this year will be easier to melt (before you look at fragmentation/drift and the impacts there?)

In 2012 we still has a sliver of '5 year+' ice along the north shore of Greenland..... no longer any ice of that age on the plots....

Again I'd caution that 'older ice' has undergone at least 1 'bottom melt' ends of a melt season so will have a much younger 'keel' of ice from the next refreeze season it encountered so all may well not be as it first appears?

Time to watch developments a little closer methinks?

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The next 5-7 days looks about as rough as you could get for the time of year. Still pretty much peak insolation with a strong high pressure aloft, little cloud and decent warmth spreading across much of the Arctic.

I think any idea that this summer will be a recovery summer compared to the last couple looks very unlikely now after a relatively ok May compared to recent years and ok previous winter.

 

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10 hours ago, Steve Murr said:

Another century drop today puts 2020 at the lowest ever ice at this point in July...

Yet according to the NSIDC, its 8th lowest... 

Of course couple of caveats, NSIDC uses a 5 day average and a lower resolution but even so, they are not usually that far apart. According to the NSIDC we been above 2012 for a good while now(and well ahead of 2010) whilst on JAXA, we not been above 2012 once.

I do believe in the JAXA charts more mind because of the higher resolution but its interesting too see nonetheless.

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Posted (edited)
1 hour ago, Geordiesnow said:

Yet according to the NSIDC, its 8th lowest... 

Of course couple of caveats, NSIDC uses a 5 day average and a lower resolution but even so, they are not usually that far apart. According to the NSIDC we been above 2012 for a good while now(and well ahead of 2010) whilst on JAXA, we not been above 2012 once.

I do believe in the JAXA charts more mind because of the higher resolution but its interesting too see nonetheless.

Are you sure it's 8th? Latest update appears to have it at 5th lowest using both the 5 and single day values, though maybe I've got something wrong.
Still, it's in a cluster for the 5 day averages, just 310k separating 2010 at the bottom with 9.27 million from 2017 at 7th with 9.58 million km2.

EDIT: I know what the issue is - leap year. The date values in the NSIDC daily extent spreadsheet is different to the values used in the Charctic graph.

Edited by BornFromTheVoid
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10 hours ago, kold weather said:

The next 5-7 days looks about as rough as you could get for the time of year. Still pretty much peak insolation with a strong high pressure aloft, little cloud and decent warmth spreading across much of the Arctic.

I think any idea that this summer will be a recovery summer compared to the last couple looks very unlikely now after a relatively ok May compared to recent years and ok previous winter.

 

I was hoping with such a strong pv last winter which gave the Arctic a decent winter that last winter would help regards this yrs summer melt. But alas doesn't seem to have made much difference. 

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https://www.bloomberg.com/news/articles/2020-07-02/arctic-fires-cause-record-jump-in-emissions-as-temperatures-soar

All very depressing news. Unfortunately the Coronavirus pandemic is hiding Global Warming news when really it should be top of the agenda. Hopefully once the pandemic is under control then we can put a focus on green recovery in order to look after the planet.

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4 hours ago, Steve Murr said:

very concerning now - Another century today (132k) -2020 putting some distance between other years now ?

I think an extent of under 4 million is about 70% likely now, I can't see the Beaufort ice surviving enough to keep extent up and the Siberian Arctic ice is all poised to melt leaving the ESS and Laptev seas ice free. I suspect a ice shape similar to 2007 is very much possible with the ice edge reaching 85 degrees north from the Siberian side but the difference being there willl be no tongue of ice in the Laptev sea. 

This is partly a result of the positive AO, the Siberian side of the basin struggled to thicken hence a lack of fast ice in both the ESS and Laptev seas because low pressure kept blowing the ice away leaving newer thinner ice to form. Time will tell whether this means the CAB will be more reluctant to melt or not but high SSTS in the Laptev may put pay to that. 

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Posted (edited)

Yep, more than 200k below the next lowest year with the ADS extent measures. High pressure and high temperatures remaining in control until at least the weekend too. 
Also just realised, we had a mega-melt week already on the daily NSIDC extent up to yesterdays update - 1.075 million km2 lost in 1 week, equivalent of an 11% drop in extent.

Edited by BornFromTheVoid
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13 minutes ago, Skullzrulerz said:

I'm no pro at this Arctic ice melt but it seems quite bad doesn't it?

Is this a record low for ice?

Most area and extent measures are showing a record low for the time of year. The latest volume update, to the end of June, had 2020 at 4th lowest, but it had undergone record fast losses in the second half of June, so it's probably close to a record low currently too.

The annual minimum extent isn't usually reached until September, but the trends in many metrics and the current forecasts lend weight to 2020 challenging the record low from 2012. Much can change between now and then, such as a switch to favourable weather for ice retention over the next 8 weeks, so it will be fascinating to watch how things unfold.

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2 hours ago, East_England_Stormchaser91 said:

That stagnant high right over the pole couldn’t have been timed any worse. Peak heating maximising itself over the most vulnerable areas. Gonna be some more huge losses this week I’m afraid. ?

Is the high causing all the extent losses though? I said at the start of the melt season, the ESS is vulnable and needs watching as the record breaking AO caused a lack of fast ice and the ice there did look vulnable. Coupled with a Siberian heatwave during June then that ice has melted quickly but what was slightly less expected was how sharp the Laptev ice has melted and the huge polyna that developed off the ESS islands. Its little wonder we are at record lows sadly. 

The ice pack does look fairly compact though and I do believe dispersion can be just as bad for the ice and actually can flatter things in terms of extent. 2019 finished below 2016 but the former had a far more compact ice cover than 2016.

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To be honest, the past week of observations in the Arctic have eradicated what uncertainties I had regarding the impact of sunlight on the high Arctic when it occurs within a strong anticyclone, within a few weeks of the summer solstice and with surface temps even slightly above zero. It hits hard & fast, leading to widespread melt pond formation.

The responses in extent and area were more dramatic than I anticipated, even taking into account the misreading of melt ponds as open water by satellites, which will be affecting area measures especially.

My main concern has always been the volume losses. We might lose the most important (...or, possibly, the only) gain that came from the relatively cold, low-dominated winter of 2019-20. The mid-month PIOMAS updated is awaited anxiously... still at least a week away, during which time forecast models are keen to persist the strong high in a near-central position. 

850s drop a little but the albedo feedback should enable sunlight to continue hitting hard wherever melt ponds persist as opposed to draining away.


Longer-term, best case scenario would be for the high to relax to a slack, 'gently' settled regime with no strong weather systems moving across the high Arctic.

Worst case scenario would be deep lows moving very near or over the CAB, dispersing the ice back out (after compaction beneath the central circulation of the anticyclone) into the warmed peripheral seas on the Atlantic & Asian sides.

Unfortunately, those warmed sees raise the likelihood of at least one deep storm occurring in that area, as a result of steep temperature gradients and more available moisture than usual for latent heat release. This being why I see 'gently settled' as a best scenario, as opposed to neutral - we need something aloft to suppress instability.

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2 hours ago, Singularity said:

To be honest, the past week of observations in the Arctic have eradicated what uncertainties I had regarding the impact of sunlight on the high Arctic when it occurs within a strong anticyclone, within a few weeks of the summer solstice and with surface temps even slightly above zero. It hits hard & fast, leading to widespread melt pond formation.

I'm still not too convinced the losses are all down to this high pressure cell, I think some of it will be down to the ESS ice melting away which would of happened regardless, the Laptev compaction and retreat is impressive and the winds from the high is playing a role there. The same thing is happening with the Atlantic front also. We also got Hudson Bay ice thinning and melting and because of the record lows Siberian ice, I'm not surprised we are at record lows sadly. Its going to be a real struggle to finish above 4 million because your relying on the Beaufort sea to hold up and dispersion not to be too widespread either and I'm not convinced either will occur sadly. 

Also this is a true Arctic high and not one that is dragging heat at lower heights or from the land masses and there has been clouds rotating around the high so still large parts of the basin has been cloudy at times even the CAB albeit today's worldview suggest it's alot clearer over the CAB. 

I'll still predict an ice shape similar to 2007 but without the Laptev part of the ice and that will likely mean an extent of below 4 million. 

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Further huge losses on ADS extent again today, nearly a double century. Got a gap of well over quarter of a million km2 to the next lowest year. However, the visuals show a huge flash melt in Hudson Bay. How real that is can't be determined until tomorrow at the earliest.

HudsonIceADS.thumb.gif.809b5b586da246d09eb662e0567d1cc8.gif

In terms of the cause of the current rapid losses... it's tricky, and probably not a whole lot of use, to pin it on any one thing. We have the preconditioning of the ice during May and June (widespread early melt ponding - a key feature of 2012), then we had the Siberian heatwave that's occasionally pushed warm air over the Eurasian Arctic (producing record low ice values here) and in recent weeks we've seen high pressure dominate during the 24 hour daylight, which is also likely to be increasing the SSTs across the areas currently free of ice, which may lead to enhanced melting later this month and into August.

On top of the above, we still had a relatively low volume to begin with and those volume measurements aren't as reliable as extent and area, so there's the potential that volume was lower than thought. We also have the reduction in aerosols due to the COVID induced industrial slowdown. There's going to be a bunch of other factors too

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3 hours ago, BornFromTheVoid said:

Further huge losses on ADS extent again today, nearly a double century. Got a gap of well over quarter of a million km2 to the next lowest year. However, the visuals show a huge flash melt in Hudson Bay. How real that is can't be determined until tomorrow at the earliest.

HudsonIceADS.thumb.gif.809b5b586da246d09eb662e0567d1cc8.gif

and in recent weeks we've seen high pressure dominate during the 24 hour daylight, which is also likely to be increasing the SSTs across the areas currently free of ice, which may lead to enhanced melting later this month and into August.

Again we are seeing analysis where we are assuming high pressure in the Arctic means clear blue skies and sunshine but a look at worldview shows that is not necessary the case. You mention sunshine over open areas of water but actually most open water areas such as the Laptev, Chukchi and the ESS has been largely cloudy recently and even the CAB has been cloudier at times as areas of shallow troughing heading around the high. There is some areas which are receiving sunny weather but the reason why this high is not as sunny as one might think is probably down to the fact its an Arctic high rather than a ridge from the landmasses which means there is much less drier air in the Arctic. 

The ice is getting compacted so extent is reducing, it really is now damage limitation and it will be a miracle if we finish above 4 million. You never know with the Arctic though. 

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