Facts About the Arctic in April 2021

As part of his March PIOMAS gridded sea ice thickness update Wipneus also produced this graph of sea ice export from the central Arctic via the Fram Strait:

So far this winter export has been remarkably subdued, but that has now changed. A persistent dipole with high pressure over Greenland and low pressure over the Barents Sea is generating strong northerly winds in the Fram Strait, and even bringing some April snow showers to South West England:

Precisely how high the pressure has been over Greenland is the subject of much debate. See for example this discussion on the Arctic Sea Ice Forum about whether a new world high pressure record has just been set. Different weather forecasting models have come to very different conclusions about the mean sea level pressure of a high pressure area situated over the Greenland ice sheet, which reaches an altitude of over 3,000 metres. Here’s GFS for example, showing 1097 hPa at 06Z on April 4th:

whereas the Canadian Meteorological Centre synopsis for the same time shows a mere 1070 hPa:

At least all the assorted models agree that the isobars are closely packed over the Fram Strait, and hence some of the thickest sea ice remaining in the Arctic is currently heading towards oblivion in the far north Atlantic Ocean:

Here’s the US Navy’s sea ice drift forecast for Saturday 10th:

[Edit – April 12th]

The predicted drift of sea ice off north east Greenland towards the North Atlantic has come to pass. Here’s some empirical evidence:

Despite the recent export via the Fram Strait sea ice area in the Greenland Sea has barely changed over the past few days:

Extent has been decreasing rapidly in other peripheral seas, and JAXA’s metric is now second lowest for the date behind 2019. Other recent years are included in the graph for comparison purposes:

[Edit – April 12th]

Whilst there was a slight uptick in JAXA extent yesterday, high resolution JAXA Arctic sea ice area is once again lowest for the date in the AMSR2 record:

Watch this space!

The 2021 Maximum Arctic Sea Ice Volume

If the 2021 maximum Arctic sea ice extent is more your thing then please see the previous article:

The 2021 Maximum Arctic Sea Ice Extent

Maximum volume is still several weeks away, but let’s first of all take a look at the PIOMAS modelled volume numbers for February. They are not yet available via the University of Washington’s Polar Science Center web site, but Wipneus has once again crunched the gridded thickness numbers which are already available. Here is what they reveal:

As you can see, it will be a big surprise if the 2021 volume maximum occurs in March rather than April, and 2021 is currently 3rd lowest for the date, behind 2017 and 2018. For completeness here too is the PIOMAS thickness map for the end of February:

This does contain some surprises, such as an area of thick ice along the shore of the East Siberian Sea, but no such thing along the north coast of Greenland, the traditional bastion of “the thickest ice in the Arctic Ocean”.

The “measured” Arctic sea ice volume calculated from CryoSat-2 and SMOS thickness data has also updated to February 28th:

Note that the “near real time” figures graphed in blue will almost certainly be revised upwards when the “reanalysed” data is released in a couple of weeks. Equally certainly they will be “lowest for the date” in the 11 year record.

Here also is the CS2/SMOS thickness map for February 28th for comparison purposes:

[Edit – March 6th]

There has recently been some debate on the Arctic Sea Ice Forum about where the thickest ice in the Arctic is currently located. If you watch this ASCAT animation of the 2020/21 freezing season thus far carefully you can see there is still a large area of multi-year ice around the North Pole, in particular reaching towards Svalbard:

An equivalent area of thicker ice in that area seems to be strangely lacking in this GOFS thickness map:

By way of comparison, here’s ASCAT’s view of the 2019/20 freezing season:

For some further historical context and another ASCAT animation see also:

Where’s the Thickest Arctic Sea Ice Gone?

[Edit – March 12th]

The February 2021 update is now available on the Polar Science Center web site. As well as the latest updates on Arctic sea ice volume it also includes these thickness anomaly maps for both PIOMAS and CS2/SMOS. Note that since CryoSat-2 didn’t launch until 2010 the anomaly baseline in both cases is 2011-2020:

The ice thickness anomaly map for February  2021 relative to 2011-2020 shows a mixture of positive and normal anomalies across the Arctic with strong negative anomalies stretching from North of Greenland into the Eastern Beaufort. Strong positive anomalies exists near the East Siberian Sea, along the Siberian Coast of the Chukchi. Thicker than normal (2011-2020) ice is also present in the Beaufort. A strong positive anomaly is notable in the Laptev Sea.   CS2/SMOS satellite data show a  broadly similar anomaly pattern but the positive anomalies in the East Siberian and Chukchi Seas are much weaker.

[Edit – March 18th]

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

plus the calculated volume and anomaly thereof:

The PIOMAS model currently places 2021 at 5th lowest for the date, with thick ice still building on the shores of the East Siberian Sea. The CS2/SMOS thickness map is still showing significantly thinner ice in the same area:

[Edit – April 5th]

The end of March PIOMAS gridded thickness numbers have been mapped by Wipneus:

They show the fast ice on the shores of the East Siberian Sea getting ever thicker, but once again C2S/SMOS begs to differ on the current thickness in that vicinity:

Maximum volume is still some weeks away, but according to the available CS2/SMOS data Arctic sea ice volume is currently lowest for the date. As suggested by the discontinuity in the graph, it seems prudent to take the “near real time” values with a large pinch of salt until the reanalysed data is published, since it looks as though there is still an issue with NRT data on the Russian side of the Arctic:

By way of a contrast, 2021 is currently 6th lowest for the date in the PIOMAS data:

Perhaps maximum volume anomaly has been reached for this winter though?

[Edit – April 8th]

The March 2021 monthly update is now available on the Polar Science Center web site:

Average Arctic sea ice volume in March 2021 was 21,700 km³. This value is the fifth lowest on record for March  about  2,000 km³ above the  record set in 2017.   Monthly  ice volume was 38% below the maximum in 1979 and 25% below the mean value for 1979-2020.

The ice thickness anomaly map for March  2021 relative to 2011-2020 shows a mixture of positive and normal anomalies across the Arctic with strong negative anomalies stretching from North of Greenland into the Eastern Beaufort. Strong positive anomalies exists along the Siberian Coast. Thicker than normal (2011-2020) ice is also present in the Beaufort.

The update also includes this comparison with CryoSat-2/SMOS volume, which highlights the current divergence between the two metrics:

[Edit – April 14th]

Whilst we eagerly await the mid month PIOMAS update, and having recently validated the Great White Con homebrew volume processing with the professionals, it is not beyond the bounds of possibility that the maximum CryoSat-2/SMOS volume for 2021 will ultimately prove to have occurred on March 22nd or thereabouts:

Here too is the latest AWI “near real time” thickness map:

Watch this space!

The 2021 Maximum Arctic Sea Ice Extent

Here’s the latest graph of Arctic sea ice extent from JAXA/ViSHOP, with 2021 and 2015 highlighted:

Extent fell by over 100,000 square kilometres between February 16th and 17th! Can that steep fall continue, as it did for one more day in 2015?

Here too is Zack Labe’s 2021 overview of JAXA maximum extent over the previous couple of decades:

2015’s maximum was very early, on February 15th. Hence the current extremely tentative 2021 maximum is already both higher and later than that. The decadal average extent graphs show the date of the maximum getting later and later, and the 2010’s peaks in the middle of March.

It therefore seems likely that there is more freezing still to come this year. However lets take a look at the high resolution AMSR2 sea ice area graph for the Sea Of Okhotsk:

The recent fall in Arctic wide extent has evidently been driven by the recent rapid decline in this peripheral sea, where SMOS reveals more thin ice ripe for further melting:

In conclusion, the high res AMSR2 extent metric shows the tentative 2021 peak below that of 2015!

[Edit – February 19th]

Following another 100k decline JAXA extent is still following the 2015 playbook remarkably closely:

Animation via NASA WorldView: https://go.nasa.gov/3axTEDu

P.S. See also:

https://twitter.com/Icy_Samuel/status/1362704233854812161

[Edit – February 22nd]

Now seems like a good time to compare JAXA AMSR2 extent with the NSIDC flavour of an Arctic sea ice extent metric, based on SSMIS data. JAXA still hasn’t rebounded significantly:

but Boulder has a problem. The NSIDC’s information is stuck on February 19th:

The first conclusion to hastily jump to is that the venerable DMSP F17 satellite has finally failed, but according to Thomas Lavergne the problem is actually on the ground:

[Edit – February 23rd]

According to Thomas Lavergne the SSMIS data is flowing to OSI-SAF once again!

https://twitter.com/lavergnetho/status/1363990216965521412

Hopefully the NSIDC’s Charctic graph will update later today. Meanwhile JAXA extent is flatlining:

The current JAXA maximum still stands at 13.98 million km² on February 16th. The NSIDC 5 day average maximum is currently at 14.54 million km² on February 15th.

P.S. It’s nearly midnight UTC, and while Charctic is still stuck on February 19th this graph is now visible on the NSIDC “Arctic Sea Ice News & Analysis” page:

[Edit – February 24th]

JAXA extent is still decreasing slowly, and is now 3rd lowest for the date in their records. Here’s a comparison with previous years with comparatively low maxima:

[Edit – February 25th]

Another leg down for JAXA extent, which is now second lowest for the date:

The NSIDC’s Charctic graph is updating again, and currently looks like this:

Meanwhile via Thomas Lavergne on Twitter here’s a CMEMS forecast for a sudden surge in extent to well above the current maximum for 2021:

[Edit – February 26th]

The NSIDC extent metric seems to be suffering further problems today, but AMSR2 soldiers on:

[Edit – February 27th]

The long awaited “rebound” in Arctic sea ice extent has begun before JAXA extent reached “lowest for the date (in the satellite record!)”. Hence for completeness I’ve added in the curve for 2006:

[Edit – February 28th]

The “rebound” in JAXA extent continues apace, with a 100k gain yesterday:

The latest CMEMS forecast from Thomas Lavergne suggests this will continue for a few more days:

[Edit – March 1st]

Following another 100k km² gain yesterday JAXA extent is racing back towards the year’s high:

However high resolution AMSR2 sea ice area has yet to follow suit. Data to February 27th:

In another intriguing development, a strong cyclone is heading into the Bering Sea. Here’s a picture of it taken by the Suomi NPP satellite:

and here is the resulting “surf” forecast for the Bering Sea at midnight tonight UTC:

I cannot help but wonder what effect a huge swell directed straight at the ice edge in the Bering Sea will have.

[Edit – March 2nd]

After yet another 100k km² gain JAXA extent has breached the 14 million level and reached a new maximum for the year:

The Bering Sea cyclone has been filling in today, but is now much closer to the ice edge:

[Edit – March 3rd]

The JAXA extent trend is still up, but the rate of increase has decreased today:

Here’s a glimpse of the state of the ice in the Bering Sea following the recent cyclone:

Meanwhile NSIDC extent is still not updating, and another cyclone is heading for the Bering Sea:

Here’s the latest CMEMS forecast from Thomas Lavergne, with the added bonus of the OSI_SAF extent graph:

[Edit – March 4th]

JAXA extent is still increasing, and hence my graph is getting more crowded with earlier years:

However note that sea ice area is still well below the initial peak on February 15th:

[Edit – March 6th]

The NSIDC’s Charctic extent graph has burst into life again, to reveal extent still rising:

JAXA concurs:

High resolution AMSR2 Arctic sea ice area has also reached a new maximum for the year:

[Edit – March 7th]

JAXA extent has finally recorded another down day:

The extremely tentative new JAXA maximum is 14.14 million km² on March 5th.

Yet another cyclone is spinning on the Pacific side of the Arctic, but this one is forecast to move over the central basin rather than just the periphery. Here’s the current Environment Canada synopsis at 12Z:

Plus the US Navy’s ice drift forecast for March 10th:

[Edit – March 8th]

Another leg up for JAXA extent. Hence I’ve added 2007 to the list of years that 2021 extent is now greater than:

[Edit – March 10th]

JAXA extent is still increasing:

and the most recent in the current sequence of Arctic cyclones appears to have bottomed out with a central MSLP of 960 hPa according to Environment Canada:

By way of comparison note that the “Great Arctic Cyclone” of August 2012 reached a minimum MSLP of 966 hPa.

The most obvious effect of the passage of the cyclone has been the opening up of this by now refrozen lead along the edge of the fast ice in the East Siberian Sea:

[Edit – March 11th]

There are more Arctic cyclones on the way. Here is the ECMWF forecast for 0Z on Saturday, courtesy of TropicalTidbits:

There’s a 953 hPa MSLP cyclone over the Kara Sea, plus 970 hPa arriving in the Bering Sea. The isobars are also closely packed over the Fram Strait, so what with one thing and another it looks as though the 2021 maximum extent is still some way away.

[Edit – March 13th]

JAXA extent is declining quickly once again:

The slightly less tentative maximum is now 14.24 million km² on March 10th.

The world’s assorted meteorological offices have different opinions on the minimum MSLP of the Kara Sea cyclone. GFS went for 950 hPa, but ECMWF settled for 952:

The next sub 970 hPa cyclone is currently forecast to enter the Central Arctic from the North Atlantic in a week or so. That’s still a long way off though, so we’ll take another look at that in a few days time.

[Edit – March 15th]

JAXA extent is still declining, so the tentative maximum is looking more secure by the day. The NSIDC’s 5 day average is declining more slowly, but currently reveals a maximum of 14.75 million km² on March 12th:

The forecast cyclone on the Atlantic side of the Arctic changes from day to day and from model to model. However the ECMWF currently show it bottoming out at 959 hPa over the Barents Sea at 0Z on Sunday 21st:

[Edit – March 16th]

Sunlight is now reaching 80N and beyond, so it is now possible for MODIS to see through the clouds and observe wind driven sea ice breaking up north of Svalbard:

[Edit – March 22nd]

NSIDC 5 day averaged extent has just posted a new maximum for the year. 14.767 million km² to be (overly?) precise:

JAXA, on the other hand, seems more than content to stick with the existing maximum:

[Edit – March 25th]

All the extent metrics are now declining in unison, and the continual sequence of strong Arctic cyclones has paused for the moment. Barring unforeseen circumstances that leaves the 2021 Arctic sea ice maximum extent numbers as follows:

UH/Wipneus AMSR2 – 13.97 million square kilometres on March 11th
JAXA/ViSHOP AMSR2 – 14.24 million square kilometres on March 10th
NSIDC 5 day SSMIS – 14.77 million square kilometres on March 21st
NSIDC 1 day SSMIS – 14.87 million square kilometres on March 11th
OSI-SAF 1 day SSMIS – 14.99 million square kilometres on March 10th

P.S.

[Edit – March 30th]

The NSIDC have now issued a press release announcing the 2021 maximum extent:

Arctic sea ice has likely reached its maximum extent for the year, at 14.77 million square kilometers (5.70 million square miles) on March 21, 2021, according to scientists at the National Snow and Ice Data Center (NSIDC) at the University of Colorado Boulder. The 2021 maximum is tied with 2007 for seventh lowest in the 43-year satellite record.

Please note that the Arctic sea ice extent number is preliminary—continued winter conditions could still push the ice extent higher. NSIDC will issue a formal announcement at the beginning of April…

In addition NASA have produced a video to mark the event:

Watch this space, just in case!

Facts About the Arctic in November 2020

Arctic sea ice volume is of course far more important in the grand scheme of things. However sea extent is easier to measure, and the JAXA AMSR2 flavour thereof has now nudged into second place for the date above 2016:

[Edit – November 4th]

The PIOMAS gridded thickness numbers have been released, to reveal this end of October thickness map:

and these calculated volume graphs:

These show Arctic sea ice volume to be lowest for the date, even if extent has slipped into 2nd place.

For comparison purposes here too is the latest AWI CryoSat-2/SMOS merged thickness map:

[Edit – November 5th]

The latest edition of the NSIDC’s “Arctic Sea Ice News” has been published. Amongst other interesting information it reveals that:

Sea ice extent for October 2020 was 5.28 million square kilometers (2.04 million square miles), placing it lowest in the satellite record for the month. This was 3.07 million square kilometers (1.19 million square miles) below the 1981 to 2010 October average and 450,000 square kilometers (173,700 square miles) below the record low mark for October set in 2019. October 2020 is the largest departure from average conditions seen in any month thus far in the satellite record, falling 3.69 standard deviations below the 1981 to 2010 mean. Ice extent is far below average in all of sectors of the Eurasian side of the Arctic Ocean and in Baffin Bay.

[Edit – November 15th]

Laptev Sea ice area has finally reached a more “normal” value for the date:

However the “polynya” at ~80 N has still not yet closed:

and the ice covering the entire Siberian side of the Arctic is still very thin:

[Edit – November 18th]

The mid month PIOMAS gridded thickness numbers have been released, and Wipneus has crunched the numbers. Volume on November 15th reverted to 2nd lowest, just above 2016:

Moving on to the PIOMAS thickness map:

compare and contrast with the merged CryoSat-2/SMOS thickness data:

The area of thicker ice north of Greenland on the PIOMAS map seems to be absent from the CryoSat-2 data, although perhaps that’s an artifact of the CS2 “pole hole”?

Facts About the Arctic in October 2020

Let’s start this somewhat belated article by looking at Arctic sea ice volume. The mid month PIOMAS gridded thickness numbers have been released to reveal these volume graphs:

Modelled volume is now in a “statistical tie” with 2012 for lowest on record for mid October. Here too is the PIOMAS thickness map:

Meanwhile for comparison purposes here is the first merged Cryosat-2/SMOS thickness map of the 2020/21 freezing season, hot off the presses at the Alfred Wegener Institute:

Whichever way you look at it there certainly isn’t much ice on the Siberian side of the Arctic at the moment! However CryoSat-2 and PIOMAS don’t seem to be able to agree on where the thickest ice in the Arctic is at the moment. It certainly isn’t anywhere near the North Pole though. According to the Barents Observer:

The Arktika icebreaker will have to undergo a second test-voyage to prove its capabilities to crush thick and hard sea-ice.

Photo: Rosatomflot

After reaching the North Pole on her maiden voyage, the communication department of Atomflot sent a press release claiming the vessel to have confirmed its characteristics in ice conditions. The release also said Arktika on the way to the North Pole sailed through three meters ice thickness.

The statement was likely premature. Head of the icebreakers acceptance team, Oleg Shchapin, says new tests in the ice have to take place, news agency TASS reports.

“Ice tests are still ahead, probably this year, because now ice tests did not work out, the ice thickness was 1,1 to 1,2 meters. It was thin and loose, the icebreaker received no resistance at all,” Shchapin says.

He adds: “We tried to find a three-meters ice floe, but they did not find it.”

[Edit – October 31st]

JAXA extent is belatedly rising fast:

The next question to be answered is if and when it crosses above 2016.

Meanwhile AMSR2 suggests that the Northern Sea Route is now closed in the vicinity of the Vilkitsky Strait:

Facts About the Arctic in September 2020

A detailed dissection of the 2020 minimum of various Arctic sea ice extent metrics can be found on a dedicated thread. All other Arctic news in September will be found below. As is usually the case, let’s set the ball rolling by taking a look at Wipneus’s visualisations of the August PIOMAS gridded thickness data:

together with the computed volume:

and anomaly graphs:

PIOMAS volume at the end of August was still firmly in 3rd place behind 2012 and 2019.

[Edit – September 4th]

However Arctic sea ice extent is firmly in second place behind 2012, although that does not also apply to area:

[Edit – September 15th]

This is the first appearance of some “new ice” on one the Canadian Ice Service’s “stage of development” charts covering the Canadian Arctic Archipelago:

In this case in McDougall Sound to the west of Cornwallis Island.

[Edit – September 19th]

The mid month PIOMAS gridded thickness numbers have been released:

The computed volume is now in second place below 2019:

The minimum volume so far is on the last day of the available data, so we’ll have to wait another 2 weeks or so before coming to any conclusions about 2020 minimum Arctic sea ice volume.

One curiosity has struck me. The PIOMAS model shows Lancaster Sound almost full of sea ice on September 15th, whereas the Canadian Ice Service chart still does not:

Watch this space!

The 2020 Arctic Sea Ice Minimum Extent

I’ve been waiting for the results of the ARCUS SIPN August call, but despite the timetable specifying “26 August 2020 (Wednesday)” they’ve still not been published and I can wait no longer!

Hopefully the August “predictions” will be available soon, but for the moment let’s take a look at the July 2020 Sea Ice Outlook instead:

For the Arctic, the median July Outlook for September 2020 average sea-ice extent is 4.36 million square kilometers, essentially identical to the median prediction in the June report, with quartiles of 4.1 and 4.6 million square kilometers. For comparison, the historical record September low over the period of satellite observations was set in 2012 at 3.57 million square kilometers, and the second lowest record was 4.27 million square kilometers set in 2007. This year’s projection is close to the 2019 observed September sea-ice extent of 4.32 million square kilometers. As was also the case for the June report, only two of the outlooks project September sea-ice extent below the 2012 record. The consensus judgement against a new record low September sea-ice extent hence remains unchanged. Interestingly, as of this report, observed extent stands at a record low for this time of year.

Note that those numbers represent “September 2020 average sea-ice extent” and not the daily minimum. Let’s now take a look at the assorted different flavours of “Arctic sea ice extent” metric. Firstly here’s the NSIDC’s “Charctic” 5 day average extent:

Next here’s JAXA/ViSHOP extent, generally assumed to be a “2 day average”:

Next here’s the DMI version, which neglects to include 2012:

followed by the Alfred Wegenr Institute/University of Bremen version:

Last but not least here is our own favourite high resolution AMSR2 version of extent, plus sea ice area for good measure:

Would anybody care to play “spot the difference” with me?

[Edit – August 31st]

Stop press! The August ARCUS SIPN September average Arctic sea ice extent “predictions” have just been published. Here’s the graphical overview:

According to ARCUS:

The August Outlook is based on a total of 39 forecasts, of which 25 are new August submissions while the remaining 14 are carried over from June and July. The median August Outlook value for the September 2020 sea-ice extent is 4.30 million square kilometers, with quartile values of 4.1 and 4.5 million square kilometers. Of the 39 August 2020 contributions, 16 are based on dynamical models, 17 are based on statistical methods, 4 are based on heuristic approaches (qualitative analyses), and 2 used machine learning-based methods. The median of the August submissions is close to that from July (4.36 million square kilometers) and June (4.33 million square kilometers). The 2020 August Outlook median is higher than 2019 (4.22 million square kilometers) and lower than 2018 (4.57 million square kilometers).

[Edit – September 1st]

Following a one day decline of 51,770 km2 JAXA/ViSHOP minimum extent is now 2nd lowest in their records going back to 1979:

Just 2012 to beat!

The NSIDC 5 day average extent is now also lower than all previous minima since 1979 apart from 2012:

[Edit – September 4th]

[Edit – September 10th]

After being offline for maintenance the ViSHOP web site is up and running again this morning, to reveal:

JAXA extent stuck on 3.59 million square kilometers two days running! Perhaps the 2020 minimum is here already?

[Edit – September 15th]

A combination of central freezing with peripheral melting has resulted in high resolution AMSR2 area and extent both “flatlining” for several days:

Which means it’s still too early to consider calling the 2020 minimum for any of the assorted metrics!

[Edit – September 18th]

New ice has started appearing on the Canadian Ice Service charts of the Canadian Arctic Archipelago, and JAXA extent has just posted a 100k daily increase:

The NSIDC 5 day averaged extent is also on the increase:

Here then are the preliminary 2020 minimum extent values for the most watched metrics:

JAXA/ViSHOP – 3.55 million square kilometers on September 13th

NSIDC Charctic – 3.74 million square kilometers on September 15th

Watch this space!

Past Evidence Supports Complete Loss of Arctic Sea-ice by 2035

Our title today is shamelessly plagiarised from the “Watts Up With That” blog of our old friend Anthony Watts. However daring to be different we have redacted the initial word “Claim -“.

The WUWT blog post is bylined “Charles Rotter”, and refers to a new paper in the journal Nature Climate Change entitled “Sea-ice-free Arctic during the Last Interglacial supports fast future loss“. Here’s an extract from the abstract:

The Last Interglacial (LIG), a warmer period 130,000–116,000 years before present, is a potential analogue for future climate change. Stronger LIG summertime insolation at high northern latitudes drove Arctic land summer temperatures 4–5 °C higher than in the pre-industrial era. Climate model simulations have previously failed to capture these elevated temperatures, possibly because they were unable to correctly capture LIG sea-ice changes. Here, we show that the latest version of the fully coupled UK Hadley Center climate model (HadGEM3) simulates a more accurate Arctic LIG climate, including elevated temperatures. Improved model physics, including a sophisticated sea-ice melt-pond scheme, result in a complete simulated loss of Arctic sea ice in summer during the LIG, which has yet to be simulated in past generations of models. This ice-free Arctic yields a compelling solution to the long-standing puzzle of what drove LIG Arctic warmth and supports a fast retreat of future Arctic summer sea ice.

There’s no mention of “2035” in there, so let’s look instead at yesterday’s press release from the British Antarctic Survey:

High temperatures in the Arctic during the last interglacial – the warm period around 127,000 years ago – have puzzled scientists for decades.  Now the UK Met Office’s Hadley Centre climate model has enabled an international team of researchers to compare Arctic sea ice conditions during the last interglacial with present day.  Their findings are important for improving predictions of future sea ice change.

During spring and early summer, shallow pools of water form on the surface of Arctic sea-ice.  These ‘melt ponds’ are important for how much sunlight is absorbed by the ice and how much is reflected back into space.  The new Hadley Centre model is the UK’s most advanced physical representation of the Earth’s climate and a critical tool for climate research and incorporates sea-ice and melt ponds.

Using the model to look at Arctic sea ice during the last interglacial, the team concludes that the impact of intense springtime sunshine created many melt ponds, which played a crucial role in sea-ice melt.  A simulation of the future using the same model indicates that the Arctic may become sea ice-free by 2035.

That’s more like it! So too is the accompanying image of some melt ponds:

Melt Ponds, Arctic Chukchi Sea. Image: Julienne Strove, National Snow and Ice Data Center

The comments underneath the WUWT article are of course 99% nonsense. Let’s see if we can do better here, shall we?


Facts About the Arctic in August 2020

A new month begins today, and at the moment it looks as though it’s going to be the most interesting one since August 2012. Here once again is the satellite image of the enormous cyclone that was spinning over the Beaufort/Chukchi Seas just a few days ago:

Here too is the effect of the cyclone on the trajectory of the JAXA Arctic sea ice extent graph:

Here too is the current prognosis of the late Andrew Slater’s “Slater Probabilistic Ice Extent” 50 day forecast:

The cyclone has obviously resulted in a reduction in the rate of extent decline, but take a look at the high resolution AMSR2 “compaction” graph:

The gaps between the remaining sea ice floes have evidently increased, and hence the ice area is declining more rapidly than its extent.

[Edit – August 2nd]

Here’s an animation, based on the University of Hamburg’s AMSR2 concentration maps, which reveals the motion of the sea ice across the Beaufort and Chukchi Seas for the last two months:

Note in particular the side effects of the recent cyclone, visible at the end of the video.

Here too is a close up of the current state of the remaining ice in the Chukchi Sea, snapped by the Suomi NPP satellite through a gap in the clouds:

Plus the current open water north of Greenland. Perhaps once Polarstern has been flushed out into the open water of the Fram Strait at the end of the MOSAiC expedition she could take another look at this almost completely unexplored area of the Arctic Ocean?

[Edit – August 6th]

The latest gridded thickness data has been released by the PIOMAS team, and here are Wipneus’s visualisations:

According to the Polar Science Center:

Average Arctic sea ice volume in July 2020 was 9,300 km3. This value is  only 400 km3 above the  record minimum  value of 8,900 km3 set in 2019. This makes 2020 the fourth lowest on record for July with 2012, 2017,2019 falling just below 2020.

JAXA extent is still lowest for the date, but following the recent cyclone it looks as though it will not maintain that position for much longer:

Now we’re in the month of August it’s possible to do a direct comparison with AMSR2 data for 2012. Here’s sea ice area for the Central Arctic Basin:

[Edit – August 8th]

All of a sudden JAXA extent is in 3rd place in the race to the minimum:

However let’s also take a close look at the state of the sea ice in the Beaufort and Wandel Seas shall we?

At this juncture I reckon that come mid September second place is now more likely than first. However as always, it still all depends on the weather.

[Edit – August 9th]

Surprising as it may seem, high resolution AMSR2 Central Arctic Basin sea ice area has so far managed to keep up with the precipitous drop in 2012:

North of Greenland the clouds have cleared closer to the North Pole, to reveal this:

Fresh this morning from Terra, a rather cloudy view of the devastation near 80N, 150W:

[Edit – August 10th]

In a not entirely unexpected development one of ex Prof. Judy’s denizens is quibbling about the current condition of sea ice in the Arctic. Hence here is a close up of some “gaping holes in the sea ice cover” at 88N between Greenland and the North Pole:

[Edit – August 13th]

A nice clear view this morning of the marginal ice zone of the “Laptev Bite” and thereabouts from the Suomi satellite :

[Edit – August 16th]

JAXA AMSR2 extent has fallen below 5 million km²:

Having been flushed out of the Central Arctic through the Fram Strait the polar research vessel Polarstern is back, seemingly intent on taking a close look at the North Pole:

[Edit – August 19th]

The mid month PIOMAS gridded thickness numbers have been published:

According to the Polar Science Center model Arctic sea ice volume is currently third lowest after 2012 and 2019.

[Edit – August 24th]

Arctic sea ice area based on NSIDC concentration data is now in a “statistical tie” with 2012 for the honour of “lowest for the date” in the satellite record:


High resolution AMSR2 area isn’t far behind:

[Edit – August 24th]

A nice clear view of the disintegrating sea ice north of the East Siberian and Chukchi Seas yesterday:

Watch this space very closely for the next few weeks!

The Northwest Passage in 2020

Whilst the Northern Sea Route has opened up early this year, it will be be quite some time before the Northwest Passage follows suit. Nevertheless our old friend Northabout is currently sailing in the direction of Baffin Bay, so now seems as good a time as any to start speculating about the prospects for the Summer of 2020. The passage through Lancaster Sound is already navigable:

However as the Canadian Ice Service chart also shows, there are still some areas of 7-8/10 concentration along the Beaufort Sea coast en route to the Bering Strait. The central Canadian Arctic Archipelago is solid 9-10/10 at present, but what’s the prognosis? Here’s the final CryoSat-2/SMOS merged thickness map of the winter, from April 15th:

This suggests that the thickest ice on the usual route through the Northwest Passage for small vessels was around 1.2 meters in Larsen Sound. This seemed suspiciously thin to me, so next I tried the underlying Cryosat-2 data from AWI, which revealed this:

Suspicions confirmed. It looks like AWI are ignoring CS2 data in the CAA for 2020! Here’s how the CPOM Cryosat-2 numbers look for a similar date, which is hopefully nearer the reality:

The CAA was fairly cloud free on June 23rd, and this satellite image shows that surface melt had started across the entire central section of the Northwest Passage:

NASA Worldview “false-color”image of the Canadian Arctic Archipelago on June 23rd 2020, derived from the MODIS sensor on the Terra satellite

All in all it looks to me as though “small vessels” will be able to successfully make it through the Northwest Passage later in the summer of 2020, with thicker ice drifting south into Larsen Sound from the McClintock Channel being a potential bottleneck.

[Edit – August 1st]

Whilst there are certainly some cruise ships planning on voyaging through the Northwest Passage this summer it looks as though there will be very few yachts or other small vessels. According to Transport Canada:

To better protect Arctic communities, pleasure craft are prohibited from operating in Canada’s Arctic coastal waters north of the 60th parallel until October 31, 2020, at the earliest:

  • to limit any potential interaction with remote and vulnerable coastal communities in consideration of minimal health care infrastructure in these waterways that notably comprise the Northwest Passage as well as the territorial sea of Canada surrounding Nunatsiavut, Nunavik and the Labrador Coast).
  • to allow the Canadian Coast Guard to focus efforts on essential operations including community resupply ice-breaking, environmental response, and search and rescue.

With this proviso:

In the Canadian Arctic coastal waters, the following measures will not apply to:

Foreign pleasure craft exercising their right of innocent passage within the territorial sea. However, any such transits will be subject to receipt of a 60-day written notice in advance of arrival in Canadian Arctic coastal waters to Transport Canada, and be subject to any conditions the Minister determines necessary to ensure the protection of marine personnel and of local communities (for example, additional insurance, rescue strategy).

[Edit – August 6th]

The skies were clear over the Northwest Passage yesterday, and this is what could be seen from the Aqua satellite:

I don’t know about you, but based on that image I reckon a plucky little yacht like Northabout could just about squeeze past the remaining sea ice along the coast of the Boothia Peninsula?

However let’s also take a look at the charts of the Canadian Ice Service shall we? The daily regional maps don’t cover the “squeeze point” yet, but the weekly map dated August 3rd reveals this:

We’re forced to conclude that officially the Northwest Passage isn’t quite “open” yet!

[Edit – August 7th]

The Canadian Ice Service have extended their daily coverage to the “choke point” we looked at above:

The Northwest Passage is still not “officially” open!

[Edit – August 8th]

The southern “choke point” is still blocking the way, and winds are currently pushing ice into the north of Peel Sound:


This Sentinel 2 image from August 6th shows the Bellot Strait to be completely clear of ice, so despite that route 6 through the Northwest Passage may well be very open soon.

[Edit – August 11th]

Snow White is pleased to announce that she cut the ribbon at the 2020 Northwest Passage route 6 opening ceremony earlier today:

[Edit – August 14th]

Whilst this is no doubt only temporary, the route along the coast of the Boothia Peninsula is now blocked by an area of 7-8/10 concentration ice:

[Edit – August 16th]

Route 6 is open once again, and it is also now possible to take a circuitous route around the north of both Somerset and King William Islands without encountering anything worse than 6/10 concentration ice:

[Edit – August 25th]

As one door opens, another one closes?

[Edit – August 27th]

Making one of my periodic visits to MarineTraffic I couldn’t help but notice a “pleasure craft” approaching Bellot Strait!

Firing up a search engine revealed this intriguing news on CBC:

According to the Canadian government, he has no business being there. But 72-year-old Peter Smith is sailing the Northwest Passage anyway, in violation of COVID-19-related orders prohibiting most foreign yachts from entering Canadian waters.

Since June 1, Transport Canada has prohibited pleasure craft from operating in Arctic waters “to better protect Arctic communities” from the spread of COVID-19.

But according to a Facebook post on Aug. 20, Bobby Klengenberg, a local observer with the Inuit Marine Monitoring Program, spotted Smith’s custom yacht, the Kiwi Roa, off the coast of Cambridge Bay, Nunavut. 

Transport Canada confirmed the sighting in an email to CBC News, and said the vessel was told “to depart Canadian waters and not make landfall.”

A spokesperson said the Canadian Coast Guard will “monitor the vessel’s transit out of the region.” If Smith is indeed found to have broken the law, they wrote, the agency “will not hesitate to take appropriate enforcement action,” including penalties of up to $5,000.

Watch this space!