Winter Solstice 2025 Arctic sea ice update
Still at record low extent
Arctic sea ice extent as of December 21 was the lowest for the date in the satellite era (since fall 1978) in all the major analyses, i.e. National Snow and Ice Data Center (NSIDC), EUMETSAT OSI SAF, the Japanese Aerospace Exploration Agency (JAXA) and the U.S. National Ice Center/NSIDC Multisensor Analyzed Sea Ice Extent (MASIE). Total ice extent has been at or close to the lowest on record since early November (Fig. 1).
This record low extent is not a blip: Arctic-wide sea ice extent has been the lowest in the satellite era every day since late November (Fig. 2) in NSIDC data. So far in 2025, 106 days rank as the “lowest sea ice extent for the date”, including long stretches in late last winter and in early summer.
Unsurprisingly, the sea ice edge is poleward of the long-term median in both Atlantic and Pacific sectors of the Arctic, but as has been in the case all year, most pronounced on the Atlantic side of the North Pole (Fig. 3 left). Analysis from Met Norway shows record low ice extent for winter solstice in the Svalbard sector, and in the central Arctic Basin northeast of Svalbard, there was open water to within 400 miles (650km) of the North Pole.
Unlike summer and early autumn, except near the ice edge, ice concentrations during the winter are very high (Fig. 3 right). Large polynya (open water surrounded by sea ice) more commonly occur in the spring.
Regional sea ice extent
As is usually the case by winter solstice, some of the regional seas are completely ice covered. Where open water areas remain, ice extent on December 21 was the lowest of record in the Barents Sea, the Central Arctic basin, the Greenland Sea and Baffin Bay (Fig. 4). Hudson Bay is finally freezing over but some open water remains. While much of mainland Alaska has been significantly colder than normal this month, that cold weather has not extended as far west as the Bering Sea, where ice extent, which was above the normal for a while in early December, is now below the long term median.
Sea ice thickness
Modeled sea ice thickness from the Danish Meteorological Institute shows ice more than two meters thick is confined to near the northern Canadian Arctic Archipelago coast, with smaller areas of thick ice in the eastern Beaufort Sea and off the northeast Greenland coast (Fig 5). It’s no surprise that the model ice thickness is quite low in the Kara Sea, but thin ice is also shown in the Laptev Sea, where there is very little ice more a meter thick.
Based on this model, total Arctic sea ice volume is even lower than last year at this point in the season, and so is the lowest on record for December 21.
Ah- NM, I found it in the Danish report.
I am not a scientist; just a layman. From my uneducated perspective these declining sea ice numbers appear alarming. Is this a short term blip (less than 100 years) or, factoring in feedback loops, we looking at the possibility of an ice free summer arctic in the next 50 years?