Facts About the Arctic in July 2020

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The new month starts with JAXA extent “lowest for the date in the satellite record” by a whisker:

The high resolution Arctic sea ice area and extent graphs based on the University of Hamburg’s AMSR2 concentration data are also in “statistical ties” for that honour, in records going back to 2013:

The 2020 melting season currently seems to be a game of two (geographical) halves. The sea ice on the Siberian side of the Arctic is currently at record lows:

Whereas the Beaufort Sea is near a record high:

Currently the tell tale signs of surface melt are visible across most of the central Arctic, as are the large number of wildfires across Arctic Siberia:

NASA Worldview “false-color” image of the Arctic on July 1st 2020, derived from the MODIS sensor on the Terra satellite

[Edit – July 4th]

The June 30th PIOMAS gridded thickness numbers have been released, and here are the results of Wipneus’s number crunching:

This month including a visualisation of the increasing negative anomaly:

Watch this space!

Facts About the Arctic in June 2020

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As is our current habit this month’s report begins with the high resolution Arctic sea ice area and extent graphs based on the University of Hamburg’s AMSR2 concentration maps:

Area and extent are currently vying for second place with 2019 on the “lowest for the date” leader board, a little behind 2016 at this point in the 2020 melting season.

However following the extremely warm spring in Siberia, the sea ice area along the assorted sea that comprise the Northern Sea Route is well below all previous years in the AMSR2 record:

Another effect of the sweltering Siberian spring is evident in the melt ponds visible below the clouds across the southernmost parts of the Laptev Sea:

NASA Worldview “false-color” image of the Laptev Sea on June 1st 2020, derived from the MODIS sensor on the Aqua satellite
NASA Worldview “false-color” image of the Laptev Sea on June 1st 2020, derived from the MODIS sensor on the Aqua satellite

plus the East Siberian Sea and Chaunskaya Bay:

NASA Worldview “false-color” image of the East Siberian Sea on June 1st 2020, derived from the MODIS sensor on the Terra satellite
NASA Worldview “false-color” image of the East Siberian Sea on June 1st 2020, derived from the MODIS sensor on the Terra satellite

[Edit – June 4th]

The May 31st PIOMAS gridded thickness numbers have been released, and Wipneus has crunched the numbers:

Here too is the latest volume graph:

According to the Polar Science Center’s May 2020 update:

Average Arctic sea ice volume in May 2020 was 21,500 km3. This value is 1700 km3 above the record minimum value of 19,800 km3 set in 2017, making it the sixth lowest on record. Monthly ice volume was 39% below the maximum in 1979 and 25% below the mean value for 1979-2019. May 2020 ice volume falls 0.8 standard deviations above the trend line. Daily volume anomalies for May progressed at a fairly normal pace for recent years. Average ice thickness is in the middle of the pack for the more recent years. Ice thickness anomalies for May 2020 relative to 2011-2018 continue the April pattern and show relatively thin ice along the Russian Coast and thicker than normal sea ice in the Barents sea. There are some fairly strong positive anomalies in the eastern Beaufort and north of Greenland. This anomaly pattern is likely due to the very strong positive Arctic-Oscillation index pattern that occurred during the Winter of 2020.

There looks to be a lot of anomalously thick ice waiting to melt out on the Atlantic periphery, and it will be interesting to see how the thicker ice in the eastern Beaufort Sea fares as the melting season progresses.

As also suggested by the area graph above, the Northern Sea Route is going to be open early in 2020. In fact a ice hardened tanker has already begun its journey through, unsupported by an icebreaker:

It was the “Christophe de Margerie” that on the 19th May kickstarted this year’s shipping season across the eastern part of the Northern Sea Route. The vessel owned and operated by Russian shipping company Sovcomflot loaded up liquefied natural gas in Sabetta and is due to arrive in the Chinese port of Jingtang on the 11th June. It was the earliest east-bound shipment on the route ever for this kind of vessel.

Shipments in the Northern Sea Route 27th May 2020. Map by MarineTraffic
Shipments in the Northern Sea Route 27th May 2020. Map by MarineTraffic

By 27th May, the ship had made it almost to Wrangel Island, information from ship tracker service MarineTraffic shows. The “Christophe de Margerie” is accompanied by nuclear powered icebreaker “Yamal”.

In the wake of the almost 300 meter long vessel now follows the “Vladimir Voronin”, a vessel that is operated by company Teekay. The “Vladimir Voronin” on the 25th May left Sabetta and was on May 27th located in the Vilkitsky Strait north of the Taymyr Peninsula.

The ”Vladimir Voronin” is not accompanied by icebreaker. The “50 Let Pobedy” that escorted the ship out of Sabetta and eastwards towards the Vilkitsky Strait has now returned and appears to be on its way back to Sabetta.

[Edit – June 17th]

The mid month PIOMAS gridded thickness numbers have just been released. Here’s the thickness map:

and the volume graph:

In addition JAXA extent is now in a “statistical tie” with 2019 in the “lowest for the date” competition:

Watch this space!

Facts About the Arctic in May 2020

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Let us begin this month’s report from the far north with the high resolution Arctic sea ice area and extent graphs based on the University of Hamburg’s AMSR2 concentration maps:

Area is currently lowest for the date in the AMSR2 record. After briefly occupying that position extent has increased over the last few days of April due to winds causing sea ice to move in the direction of the far North Atlantic:



The Alfred Wegener Institute has now finished reanalysing their CryoSat-2/SMOS thickness data, and the resulting volume graph looks like this:

“Measured” Arctic sea ice volume is the lowest in the CryoSat-2 era as we head towards the main 2020 melting season, which in my calendar at least begins on June 1st. The PIOMAS modelled volume numbers should be released shortly.

[Edit – May 5th]

The April 30th PIOMAS gridded thickness numbers have been released, and Wipneus has worked his usual magic. By way of comparison with the AWI metric:

Obviously differing from CryoSat-2/SMOS, PIOMAS has 2020 volume a long way above 2017, in amongst a gaggle of other years.

[Edit – May 13th]

The middle of May is rapidly approaching, so let’s start to set the scene for the forthcoming melting season. First off here are the hi res AMSR2 area and extent graphs:

Extent is currently significantly above 2016 due to the recent “dispersion” mentioned above, but area is very close to an all time low for the date.

Next take a look at the current northern hemisphere snow cover anomalies from the Rutgers University Snow Lab:

Whilst there is a positive anomaly near Hudson Bay, there are significant negative anomalies across Siberia and Alaska. This does not augur well for sea ice retention along both the Northern Sea Route and Northwest Passage by September 2020.

Watch this space!

China’s big Covid-19 business?

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We’ve already come across Glen Owen and Harry Cole, broadcasting batty bunkum about the novel coronavirus pandemic from the platform of the Mail on Sunday. Glen and Harry are now turning their searchlight away from science, and submitting business and economics to its cold, hard glare. In an article under one of the Mail’s trademark lengthy headlines they tell to us today the tall tale of the:

“‘Suited svengalis’ who help the Chinese government decide which British businesses to buy will be investigated by MPs amid fears Beijing is using coronavirus pandemic to advance its commercial interests”

Political figures and advisers who profit by helping the Chinese regime to target British businesses are to be investigated by MPs amid growing fears that Beijing is using the cover of Covid-19 to advance its commercial interests. 

The move comes after a China backed company mounted an attempted coup at Imagination Technologies, a UK firm which designs graphic chips for apple. 

The company was sold to private equity business Canyon Bridge Capital Partners in 2017 for £550million in a deal approved by Theresa May’s Government on the basis that the company would remain subject to US laws. 

However, the organisation later moved its head office to the Cayman Islands – outside US jurisdiction. Last week, senior MPs sounded the alarm after China Reform Holdings, the Beijing-backed lead investor in Canyon Bridge, tried to take control of the firm – amid fears it planned to transfer the ownership of intellectual property to China.  

I’m afraid I’m a bear of very little brain, and it’s unclear to me what Covid-19 has got to do with the alleged “attempted coup”. Perhaps the terrible twins can elucidate?

Tom Tugendhat, the Tory chairman of the Foreign affairs Committee, warns ‘suited svengalis’ who profit from the skills they’ve acquired over years of training would face scrutiny. 

Writing in the Mail on Sunday, he says: ‘too frequently, we’ve seen those who once wrote the rules and negotiated agreements to protect us, and some who still sit in our Parliament, selling the tricks they learned in Government.’ 

This newspaper has seen correspondence linking Global Counsel, the public affairs company chaired by Peter Mandelson, to Canyon Bridge. Global Counsel’s staff includes Alex Dawson, who was working for Mrs May in Downing street when the 2017 deal was agreed.

In the correspondence, Ben Wegg-Prosser, the company’s managing director, advises Canyon Bridge over how to respond to MPs demanding reassurances over the British company’s future.

Or perhaps not. Please excuse my French, but WTF has any of that got to do with Covid-19 pandemic? Please feel free scan the rest of the article if you have a well developed sense of the ridiculous. Then you’ll no doubt be able to point out to me the Covid-19 reference(s) that I must have inadvertently blinked and missed.

I still haven’t received any answer from anyone at the Mail on Sunday following my last such enquiry, but I’m a glutton for punishment, so here we go again:

Watch this space!

(But please don’t hold your breath)

David Rose’s Great Covid-19 Con?

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Recent readers may well have arrived here because I have started commenting on the Great Covid-19 crisis? Regular readers may recall my previous Arctic sea ice altercations with David Rose? He “writes for the Mail on Sunday” according to his byline in Andrew Neil’s Spectator magazine. One or two people of a certain age may even recall the initial raison d’être of my Arctic alter ego’s blog?

David has now also turned his attention to Covid-19 in an article in the aforementioned journal, entitled “Revealed: Extinction Rebellion’s plan to exploit the Covid crisis. The group sees ‘silver linings’ in the pandemic”. Perhaps given our long familiarity with David’s “skeptical” oeuvre we might be able to reveal Andrew Neil’s “plan to exploit the Covid crisis”? That being the case, let’s dive into David’s “silver linings playbook” shall we?

As we contemplate the havoc being wrought by coronavirus, most of us see mainly sickness, death and economic ruin. Dr Rupert Read, spokesman for the climate protest group Extinction Rebellion — plus sometime Green party candidate, and associate professor of philosophy at the University of East Anglia — has rather a different view. In this pandemic, he writes, ‘there is a huge opportunity for XR… It is essential that we do not let this crisis go to waste.’

Read’s thoughts are set out in a paper entitled ‘Some strategic scenario-scoping of the coronavirus-XR nexus.’ The paper is not meant to be widely read. ‘NB, this is a confidential document for internal XR use, NOT for publication!’ he writes at the head.

Now this is of course the point in the ClimateBall™ playbook where one always poses the question “Gotta link to evidence justifying your assertions David?”

David doesn’t provide one so perhaps one might enquire instead:

[Edit – April 11th]

Perhaps you won’t be surprised to discover that neither Andrew Neil or David Rose have provided me with a link as yet? In which case perhaps one should try another tack?

Facts About the Arctic in April 2020

Extent, , , , , , , , , ,

This comes to you a couple of days early, but the clocks have just changed to British Summer Time in the once United Kingdom and there is news to impart.

JAXA Arctic sea ice extent has fallen to the lowest level for the date in their satellite era records going back to 1979. This graph shows every year since 2000:

The high resolution AMSR2 regional graphs make clear that the precipitous drop on the Pacific periphery has continued:

The current combined SMOS/SMAP Arctic sea ice “thinness” map makes clear that there is plenty more thin ice ready for melting in the Sea of Okhotsk and Baffin Bay:

There is also a large area of thin ice in the Laptev Sea, which will be interesting to watch once the 2020 melting season gets underway in earnest.

[Edit – April 1st]

Today is All Fools’ Day, but this is no joke. Thanks to the consistent polar vortex over the Northern Hemisphere winter there is currently an anomalous “ozone hole” over the North Pole. As recently described in Nature:

A vast ozone hole — probably the biggest on record in the north — has opened in the skies above the Arctic. It rivals the better-known Antarctic ozone hole that forms in the southern hemisphere each year.

Record-low ozone levels currently stretch across much of the central Arctic, covering an area about three times the size of Greenland. The hole doesn’t threaten people’s health, and will probably break apart in the coming weeks. But it is an extraordinary atmospheric phenomenon that will go down in the record books.

“From my point of view, this is the first time you can speak about a real ozone hole in the Arctic,” says Martin Dameris, an atmospheric scientist at the German Aerospace Center in Oberpfaffenhofen.

Here are the latest graphics from the “Arctic Ozone Watch” section of the NASA web site:

Observations made during the still ongoing MOSAiC expedition, have confirmed the satellite derived measurements:

This year, powerful westerly winds flowed around the North Pole and trapped cold air within a ‘polar vortex’. There was more cold air above the Arctic than in any winter recorded since 1979, says Markus Rex, an atmospheric scientist at the Alfred Wegener Institute in Potsdam, Germany. In the chilly temperatures, the high-altitude clouds formed, and the ozone-destroying reactions began.

Researchers measure ozone levels by releasing weather balloons from observing stations around the Arctic (including the Polarstern icebreaker, which is frozen in sea ice for a year-long expedition). By late March, these balloons measured a 90% drop in ozone at an altitude of 18 kilometres, which is right in the heart of the ozone layer. Where the balloons would normally measure around 3.5 parts per million of ozone, they recorded only around 0.3 parts per million, says Rex. “That beats any ozone loss we have seen in the past,” he notes.

I’ve previously conjectured about the potential effect of the strong polar vortex on Northern Hemisphere snow cover this Spring, and here’s NOAA’s current snow extent graph:

JAXA extent’s precipitous recent decline has abated, and it’s now 5th lowest for the date in the satellite era:

[Edit – April 4th]

Here’s the March 31st PIOMAS Arctic sea ice gridded thickness map:

together with the traditional volume graph:

Wipneus comments on the Arctic Sea Ice Forum that:

Ice is thickening impressively against the Canadian Archipelago and North Greenland.

That is indeed the case with the PIOMAS “modelled” numbers, but is much less obvious in the latest CryoSat-2/SMOS “measured” thickness map where ice over 4 metres thick is still conspicuous by its absence North of Greenland:

Plus a bonus graph for “Turbulent Eddie”, who suggests that:

[There’s] not much thick ice on the East Coast of Greenland, indicating the increase was from reduced loss through the Fram Strait?

together with the latest AARI ice age map:

[Edit – April 6th]

Here’s the latest update of our novel NRT volume metric:

I’ve applied a crude correction to the still problematic NRT data so that it at least coincides with the reanalysed data on March 14th. Whilst we await the reanalysed numbers for the rest of March and early April it looks as though Arctic sea ice volume reached at least a temporary peak on March 20th 2020.

[Edit – April 19th]

Here’s another update of our novel NRT volume metric, still incorporating my “fudge factor”:

Note also this handy hint from Stefan Hendricks on Twitter:

[Edit – April 21st]

Wipneus has crunched the mid month PIOMAS gridded thickness numbers. Here’s the result:

The discrepancy between the PIOMAS model and the CryoSat-2 “reality” is still very evident.

[Edit – April 25th]

With another week’s worth of reanalysed data now processed, it now seems certain that the CS2/SMOS Arctic sea ice volume maximum was 18469 km³ on April 6th:

[Edit – April 28th]

The high resolution AMSR2 area and extent metrics are now both “lowest for the date” in the AMSR2 record:

JAXA/ViSHOP AMSR2 extent isn’t quite there yet:

The 2020 Maximum Arctic Sea Ice Extent

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As Zack Labe has recently pointed out, in 2015 the Arctic sea ice maximum extent based on the JAXA numbers had already occurred on February 15th:

Perhaps it’s time we started paying attention this year! However the National Snow and Ice Data Center reported a significantly later date in 2015:

On February 25, 2015, Arctic sea ice extent appeared to have reached its annual maximum extent, marking the beginning of the sea ice melt season. This year’s maximum extent not only occurred early; it is also the lowest in the satellite record. However, a late season surge in ice growth is still possible.

Each year we keep track of the assorted Arctic sea ice metrics over the next month or so, and they rarely agree on the date of maximum extent, and never agree on the sea ice extent on that date! The reason for that is explained in a 2017 paper entitled “Variability and trends in the Arctic Sea ice cover: Results from different techniques“:

Reports on the sea ice cover have been provided by different institutions using basically the same set of satellite data but different techniques for estimating key parameters such as ice concentration, ice extent, and ice area. In this study, a comparison of results from four different techniques that are frequently used shows significant disagreements in the characterization of the distribution of the sea ice cover primarily in areas that have a large fraction of new ice cover or significant amount of surface melt.

In due course we’ll look at the metrics from a variety of different institutions, but let’s start with JAXA, comparing 2020 with 2015 and the 2010s average:

Extent is clearly increasing just at the moment! Will the next peak prove to be the maximum for the year or will we have to wait another month or more to find out that value, as suggested by the average?

Compare and contrast JAXA extent with Wipneus’ high resolution AMSR2 extent and area:

Perhaps the 2020 maximum area has already been reached?

[Edit – February 25th]

Or perhaps not! We’re playing mix and match this morning, since Wipneus’s new numbers haven’t been released yet. Here UH AMSR2 high resolution Arctic sea ice area from February 23rd:

Plus JAXA extent for the 24th:

[Edit – February 27th]

Tony Heller’s latest sea ice themed article claims “Normal Sea Ice Extent At Both Poles”. Hence today’s JAXA extent graph includes the averages for previous decades:

Extent is evidently increasing once again, and is even more evidently well below what passed for “normal” in the twentieth century!

Let’s also compare the Pacific periphery:

with the Atlantic side of the Arctic Ocean:

The Bering and Okhotsk Seas will be sea ice free by the time September 2020 arrives. How about the Kara, Barents and particularly Greenland Seas though?

[Edit – February 29th]

Arctic sea ice maximum volume usually occurs in April, but nonetheless let’s keep an eye on the metric that most nearly measure the “amount” of sea ice left in the Arctic in 2020. Here’s our “measured” CryoSat-2/SMOS volume metric, using reanalysed data up to February 12th:

PIOMAS “modelled” volume for February should be released soon, but getting back to extent the JAXA flavour has been setting new highs over recent days:

whereas the NSIDC’s Charctic 5 day averaged extent has not!

[Edit – March 6th]

Here’s the February PIOMAS gridded Arctic sea ice thickness map, courtesy of Wipneus on the Arctic Sea Ice Forum:

plus the traditional modelled volume graph:

As angech has pointed out elsewhere, according to the PIOMAS team:

CryoSat-2 data show total volume for February 2020 substantially lower than PIOMAS with 2020 Febuary near record low levels over the 2011-2020 period

[Edit – March 19th]

The March mid month PIOMAS numbers have been crunched by Wipneus. Here’s how things look at the moment:

For comparison purposes here’s the current CryoSat-2/SMOS Arctic sea ice thickness map:

[Edit – March 20th]

After flatlining for a long time JAXA extent has posted significant declines for two days running. There’s been no official announcement from the NSIDC as yet, but it now seems safe to conclude that there won’t be a late surge in extent similar to 2010. Here’s the current JAXA graph:

plus NSIDC’s 5 day averaged extent:

Hence the (still provisional!) maximum numbers for 2020 are:

JAXA/VISHOP AMSR2 – 14.45 million square kilometers on March 3rd
NSIDC 5 day SSMIS – 15.05 million square kilometers on March 5th

The University of Hamburg’s JAXA AMSR2 concentration data seems to have suffered an outage over the crucial period. Hopefully the gaps will be filled in due course. However more recent regional graphs  reveal the following:

The recent declines in overall extent are evidently driven by declines on the Pacific periphery.

The Great White Con 2020 “New Einstein” Award

Satire, , , ,

Our regular reader(s) have grown to love the amazing prizes awarded to the winner of our annual Great White Con “New Einstein” Award . The jury has now finished its deliberations on the 2019 award in the traditional smoke filled igloo just outside the Great White Con Ivory Towers, not far from Santa’s secret summer swimming pool. I am pleased to be able to announce that the first prize of the loan of a polar bear suit kindly donated by the Daily Telegraph plus a battered big board from Cotty’s quiver has been awarded to the ever spiteful Spike55 at Tony Heller’s unReal Climate Science blog, with:

You’re an idiot. A LIAR. A child-minded troll. And a slimebag con-man.

Here for your viewing pleasure is the very first “New Einstein” contestant of 2020, astonishingly early since we’re still in the midst of the 2019/20 Arctic sea ice freezing season!

1) Michael Liebreich on Twitter, with:

2) Thomas Barlow, in a “Personal Message” following the introduction of a new moderation regime on the Arctic Sea Ice Forum with:

Fuck off, clique hobbit, shit-for-brains.

Jim Thomson Waves in Ice Webinar

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I only found out about this webinar after it had already started. My Arctic alter ego somewhat cheekily suggested to the Arctic Research Consortium of the United States (ARCUS for short) that our research into waves in the Arctic was ahead of theirs, and was rather surprised when they agreed with “her”!

Fortunately the “Ocean Waves in the New Arctic” webinar was recorded, and here it is in its entirety:

See if you can spot the question “Snow White” asked?

Amongst other things, Jim mentioned in his talk coastal erosion due to increased wave action.  That included a flooding event at Utqiaġvik (Barrow) in 2017. Here’s what happened during a similar event there in 2015:

Photograph by Brittni Driver via Alaska Dispatch News
Photograph by Brittni Driver via Alaska Dispatch News

Barrow Battered By Big Waves

Jim also mentioned the erosion of the permafrost bluff at Drew Point, exacerbated by increasing wave action. According to a recent article on that topic:

Eroding permafrost coasts are likely indicators and integrators of changes in the Arctic System as they are susceptible to the combined effects of declining sea ice extent, increases in open water duration, more frequent and impactful storms, sea-level rise, and warming permafrost.

Our results show that mean annual erosion for the 2007–2016 decade was 17.2 m yr−1, which is 2.5 times faster than historic rates, indicating that bluff erosion at this site is likely responding to changes in the Arctic System.

Here’s a video of permafrost disappearing into the Beaufort Sea in 2008:

[Edit – March 1st]

A slightly less technical video from the University of Washington featuring Jim Thomson and some big waves in the New Arctic:

Where’s the Thickest Arctic Sea Ice Gone?

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In the absence of the usual mid month PIOMAS Arctic sea ice volume update I’m being moaned at by “angech” over on Judith Curry’s “Climate Etc.” blog:

Any ideas on why PIOMAS mid month update not out, other than not wanting to show a big recovery?

Unlike any of Judy’s denizens I checked out the comparatively new merged CryoSat-2 plus SMOS thickness maps from the Alfred Wegener Institute. “Measured” rather than “modelled” data must be a good thing surely?

Just in case there’s some significant difference between the “reanalysis” and “operational” versions of that product, here is the AWI’s most recent reanalysed Arctic sea ice thickness map, for the week ending January 11th:

together with the same date from the previous two years:

Make sure to take a close look at the white areas north of Greenland and the Canadian Arctic Archipelago showing sea ice over 4 metres thick.

Over the winter of 2018/19 ASCAT revealed that there was a relentless movement of multi-year ice towards both the North Atlantic and the Beaufort Sea.

Not unexpectedly that meant that ice in the northern Barents Sea was slow to melt out in the summer of 2019:

whilst after a fast start the melt in the Beaufort Sea also suffered a “brief hiatus” in June before ultimately melting out almost completely as well:

Perhaps a significant amount of the multi-year ice that survived the winter of 2018/19 has now simply melted away in warm water, to be replaced by much less robust first year ice in the area between the North Pole and the Siberian coast? It will be very interesting to see what the next PIOMAS update in early February reveals.

[Edit – February 4th]

The next PIOMAS update referred to above has now arrived. Here’s the Polar Science Center’s graph:

Over on Climate Etc. angech is already exclaiming:

Strange it did go up a fair bit the old PIOMAS.
No publicity at the usual going down sites.

Actually it’s not at all strange, because thus far this winter the polar vortex has been remarkably well behaved. By and large cold air air has stayed in the Arctic. There hasn’t been much in the way of cold air intrusions into mid latitudes or warm air intrusions into the Arctic.

Hence it’s not at all surprising that the thickness of sea ice in the Arctic has been increasing slightly more quickly this winter than in other recent years. By way of some longer term context, here are the official Polar Science Center min/max trends:

[Edit – February 4th PM]

Wipneus has just released the January PIOMAS gridded thickness map. Here it is:

[Edit – February 5th]

As is all too frequently the case, AdR and other commenters below get very excited about trivial increases in sea ice extent without considering snow extent. One side effect of the lack of cold air outbreaks into mid latitudes so far this winter currently looks like this:

[Edit – February 6th]

The AWI and PIOMAS sea ice thickness maps above look somewhat different at first glance. That being the case, I’ve written a program to crunch the AWI numbers. Here’s the result:

The source code plus raw and processed data can be accessed via the Arctic Sea Ice Forum:

“CryoSat-2/SMOS Arctic Sea Ice Volume”

[Edit – February 10th]

Further support for my “polar vortex” theory, from Judah Cohen no less!

[Edit – February 16th]

Here’s the latest update of our novel NRT volume metric:

Please note that there is a known problem with the NRT data from January 31st onwards.

Here too are Wipneus’ latest high resolution AMSR2 area and extent graphs:

[Edit – February 18th]

Wipneus has released his usual mid month PIOMAS update on the Arctic Sea Ice Forum:

I am forced to ponder once again why the CryoSat-2/SMOS thickness “measured” numbers just above seem to be more at variance with PIOMAS in 2020 than in previous years:

[Edit – February 22nd]

Here’s another weekly NRT volume update:

This time I’ve left off the NRT data from February 6th onwards, since the “issue” referred to above obviously hasn’t been solved yet. As an added bonus here’s a graph showing the trends (or lack thereof) on 3 dates during the October to April freezing season: