In midwinter, the seas around Svalbard are usually covered by expanding Arctic sea ice, forming a continuous barrier between the archipelago and the central Arctic Ocean. In December 2025, however, satellite observations revealed a striking departure from these typical conditions, with large areas of open water persisting north and east of the islands.
This absence of sea ice north of Svalbard formed part of a wider pattern across the Arctic during the month. Arctic sea ice extent remained well below average, reaching the lowest December level in the 47-year satellite record. The Copernicus Climate Change Service (C3S) reported that the average extent in December 2025 was 11.3 million km², about 1.1 million km², or roughly 9%, below the 1991–2020 average. This marked the second consecutive year in which December sea ice extent reached record-low levels for the time of year.
These conditions are illustrated by a Copernicus Sentinel-1 image acquired on 14 January 2026, which shows extensive open water northeastern of the Svalbard archipelago, where sea ice would normally be present at this stage of the season.
Regionally, the strongest negative sea ice concentration anomalies were observed in the western Eurasian sector of the Arctic. This included the northern Barents Sea and the area between Svalbard and Franz Josef Land, as well as parts of the western Kara Sea. In these regions, much-below-average sea ice concentrations coincided with much-above-average surface air temperatures during December. Similar ice deficits were also present in the northeastern Canadian sector, including Hudson Bay and parts of Baffin Bay.
While Arctic sea ice extent continued its seasonal growth through December, record-low daily values persisted for most of the month. On 31 December, daily sea ice extent reached its lowest value on record for that date, at 12.45 million km². Together, these observations point to increasingly frequent midwinter periods in which Arctic sea ice fails to recover to levels seen in previous decades.
Featured image credit: European Union, Copernicus Sentinel-1 imagery
