JAXA have updated their visualisations of Arctic sea ice extent data. The “traditional” 2 day average graph is now labelled “preliminary”, and currently shows 2026 in a tie with 2020 for third lowest for the date:
5 day averaged “confirmed” data is also available, including regional graphs. By way of example here’s JAXA’s latest extent graph for the Bering Sea, dated May 15th:
The Alfred Wegener Institute’s sea ice concentration data reveals open water in the Beaufort, Chukchi, East Siberian and Laptev Seas:
In the eastern Beaufort Sea albedo is further reduced by the waters of the Mackenzie River encroaching upon the fast ice off the river delta:
“False colour” image of the Mackenzie Delta on May 17th from the MODIS instrument on the Terra satellite
The monthly summary of atmospheric conditions over the Arctic during April 2026 reveal part of the reason for the open water. A persistent area of high pressure over the Beaufort Sea:
The NSIDC monthly average extent graph for April shows 2026 second lowest behind 2019:
Further north, melt ponds have begun to form in Darnley Bay:
“False colour” image of Darnley Bay on May 21st from the MODIS instrument on the Terra satellite
and Coronation Gulf:
“False colour” image of Coronation Gulf on May 21st from the MODIS instrument on the Terra satellite
[Update – May 26th]
According to the Canadian Meteorological Centre a cyclone in the Central Arctic achieved a minimum central pressure of 977 hPa at 12:00 UTC yesterday:
[Update – May 28th]
Melt ponds are now clearly visible in Chaunskaya Bay, and have begun to form further west along the Chukotka coast:
“False colour” image of Chaunskaya Bay on May 28th from the VIIRS instrument on the NOAA 21 satellite
[Update – May 29th]
In an early start to traffic along the Northern Sea Route this year, nuclear icebreaker Ural has just led LNG tanker Christophe de Margerie through the Vilkitsky Strait.
In other news, cracks have started to appear in the fast ice blocking the Nares Strait:
“True colour” image of the Nares Strait on May 29th from the MODIS instrument on the Terra satellite
[Update – May 31st]
Another cyclone has reached the Central Arctic, this time entering from the Barents Sea. This one reached a minimum central pressure of 978 hPa at 00:00 UTC this morning:
I was hoping that the September PIOMAS gridded thickness data would have been published by now, but no such luck. Reverting to JAXA/ViSHOP extent, after flatlining for most of September the refreeze has started in earnest over the last two weeks. Extent is currently 12th lowest in the satellite era:
The latest sea ice concentration map from Lars Kaleschke of the Alfred Wegener Institute, based on AMSR2 data, reveals plenty of new ice in the Beaufort Sea, plus a bit more to the north of the Laptev Sea:
The latest sea ice “stage of development” charts from the Canadian Ice Service confirm that, and reveal more new ice that has yet to show up in the AMSR2 data:
[Update – October 11th]
In the continuing absence of PIOMAS gridded thickness data (see below), here’s the latest SMOS/SMAP “thin ice thickness” map:
It appears to be badly affected by radio frequency interference on the Atlantic side of the Arctic. Here’s the raw SMOS map:
Further to a previous conversation on the subject, here’s the final NSIDC annual average extent graph for September:
As anticipated, 2025 annual average extent has proved to be the lowest in the satellite era.
[Update – October 16th]
I was hoping that the September edition of the NSIDC’s “Sea Ice Today” analysis would have been published by now, but no such luck. Here’s the latest data announcement from the NSIDC:
Effective October 15, 2025, due to non-renewed funding, NSIDC has suspended or reduced several Sea Ice Today tools and services.
Sea ice annual maximum and minimum announcements (typically occurring in March and September)
Previously-published Sea Ice Today analysis posts will remain online. The discontinued Sea Ice Today products will no longer update or be maintained, and will be removed in the next several weeks.
In Sea Ice Today’s absence, here’s the MSLP and 925 hPa temperature maps for September, usually contained in the monthly analysis articles:
Plus a hastily constructed graph of the monthly average extent for September:
The Arctic sea ice volume derived therefrom is 5.43 thousand km³. The data is accompanied by the following “Product Degradation Warning”:
SMOS input data continues to be affected by persistent and frequent radio-frequency interference (RFI) in the Barents, Kara, and Laptev Seas, resulting in missing thin ice thickness measurements. Consequently, sea ice thickness estimates for this region in the product will rely exclusively on radar altimeter data, which may lead to higher reported values than would have been obtained using SMOS.
[Update – October 27th]
The PIOMAS gridded thickness data for September 2025 has been belatedly released:
The associated volume graph reveals that the 2025 minimum modelled Arctic sea ice volume was 3.87 thousand km³ on September 12th, which is the 2nd lowest minimum in the PIOMAS record going back to 1979:
Whilst we’re on the topic of sea ice volume, here’s the latest “measured” volume graph:
Note the proviso about recent SMOS data above, and also that the version 3.00 data from AWI is currently only available beginning in Autumn 2023. Prior years shown on the graph above are based on version 2.06 data, which amongst other things does not incorporate Sentinel 3 data.
[Update – October 29th]
Much of the Siberian side of the Arctic Ocean has now refrozen:
There is a significant difference between progress of the refreeze on the the Pacific and Atlantic sides of the Arctic. Extent in the Chukchi Sea is currently highest for the date in the AMSR2 record:
However, refreeze of the Kara Sea has yet to begin, and extent is currently lowest for the date in the AMSR2 record:
Pan Arctic JAXA/ViSHOP extent is now 6th lowest in the satellite era:
At the beginning of last month JAXA/ViSHOP extent was third lowest for the date in the satellite era. With the date of the 2025 minimum extent rapidly approaching that is no longer the case:
Whilst JAXA extent is now 10th lowest, PIOMAS volume remains second lowest for the date:
Here’s the associated thickness map. Note the change of scale from last month
Compare and contrast that map with the AWI’s sea ice concentration map, particularly in the Beaufort Sea area:
Some “pleasure craft” are currently heading up the west coast of Greenland en route to the Bering Strait via Lancaster Sound and one of the assorted routes through the Canadian Arctic Archipelago. For those of you unfamiliar with the geography of the Northwest Passage, here are couple of hopefully helpful maps:
Whilst there is still ice blocking the route across Baffin Bay from Greenland, the Canadian Ice Service has already started daily coverage of the heart of the southern route through the Northwest Passage. There’s plenty of open water in Lancaster Sound and low concentration sea ice in Prince Regent Inlet:
Further south there is also open water in the Coronation Gulf, but the fast ice between Peel Sound and King William Island has not yet started breaking up:
This slightly cloudy satellite image of the Canadian Arctic Archipelago also shows that the exit of the northern route via McClure Strait into the Beaufort Sea is already navigable:
Since a certain “sceptic” has recently been comparing 2024 sea ice extent to “20 years ago”, here’s the current JAXA/ViSHOP extent graph of selected years, including 2004:
The CryoSat-2/SMOS merged Arctic sea ice volume graph finishes on April 15th, but older data is being reanalysed and here is the latest version:
The gap in the near real time data due to the problem with the SMOS satellite during the first half of March has been filled in, but the result doesn’t look very convincing to say the least!
The PIOMAS gridded thickness data for April 2024 is now available. Here’s the end of month volume graph:
Starting this month with a look at assorted volume/thickness data, here is the CryoSat-2/SMOS merged Arctic sea ice thickness map for March 31st:
Plus the associated volume graph, which still suffers from a gap in the near real time data due to the problem with the SMOS satellite during the first half of March:
The PIOMAS gridded thickness data for March 2024 is also available. Here’s the end of month thickness map:
Plus the calculated volume graph:
Especially for Peter, here too is the DMI’s chart of monthly Arctic sea ice volume for March:
By way of a change, which is allegedly as good as a rest, let’s start the new month with a very pretty and almost cloud free “pseudo-colour” image of the Lena Delta and adjacent areas of the Laptev Sea:
“False colour” image of the Lena Delta on June 1st from the MODIS instrument on the Aqua satellite
Arctic sea ice extent in early April is singularly unexceptional. Here’s the AWI AMSR2 version:
Things start to become more interesting when looking at the third dimension. Here’s the PIOMAS gridded thickness map for March 31st:
and the CryoSat-2/SMOS map for the same date:
Note the differing distribution of thick ice north of Greenland and the Canadian Arctic Archipelago between the two maps. Note also the area of thinner ice along the coast of the Beaufort Sea visible on the CS2/SMOS map.
By way of explanation for that phenomenon see the March sea level pressure map from the latest edition of the NSIDC’s Arctic Sea Ice News:
This website uses cookies to improve your experience. We'll assume you're ok with this, but you can opt-out if you wish. Cookie settingsACCEPT
Privacy & Cookies Policy
Privacy Overview
This website uses cookies to improve your experience while you navigate through the website. Out of these, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website. We also use third-party cookies that help us analyze and understand how you use this website. These cookies will be stored in your browser only with your consent. You also have the option to opt-out of these cookies. But opting out of some of these cookies may affect your browsing experience.
Necessary cookies are absolutely essential for the website to function properly. This category only includes cookies that ensures basic functionalities and security features of the website. These cookies do not store any personal information.
Any cookies that may not be particularly necessary for the website to function and is used specifically to collect user personal data via analytics, ads, other embedded contents are termed as non-necessary cookies. It is mandatory to procure user consent prior to running these cookies on your website.
