Lowest Sea Ice Level in the Arctic in Five Years
Around March 22, the Arctic sea ice reached its annual maximum for 2025. There has been a very low development of sea ice throughout the winter, with a sharp reduction in January. By the end of the season, the ice approached the 2023 peak but just fell short of it. As a result, the ice cover in 2025 was lower than the past five years.
Publisert 27. March 2025
Image of the Greenland Sea, taken during a cruise in Mars. Photo: Ellen Viste
Warm Period in January
According to Copernicus, sea ice extent experienced a significant drop in January, falling by about 0.3 million km², an area roughly the size of Italy, in less than a week. January is typically a time of ice expansion, with ice nearing its maximum. Such a reduction is highly unusual for that time of year.
The reduction coincided with a warming event over the Greenland Sea and the Svalbard region. During the heat outbreak, sea ice was already near record-low levels for the season.
Graph showing the development of sea ice in the Arctic. The blue line shows the sea ice development for 2025. Source: NOAA https://nsidc.org/sea-ice-today/sea-ice-tools/charctic-interactive-sea-ice-graph
Retreat in Svalbard
The northern Barents Sea and the area north of Svalbard are two regions where we have seen the most significant reductions in sea ice cover during winter in recent decades. This is according to Marius Årthun, research leader for the Polar research group at the Bjerknes Centre.
"In these two areas, warm Atlantic water flows into the Arctic. This has always been the case, but in recent decades, these warm, ice-free areas have gradually shifted northward. We refer to this as the 'Atlanticization' of the Arctic," he explains.
More ice east of Greenland
But not all areas in the Arctic are experiencing the same decline in sea ice, says Kjetil Våge, professor at the Department of Geophysics (University of Bergen) and researcher at the Bjerknes Center.
"Along most of the Greenland slope between the Fram Strait and Denmark Strait, there has been more ice this winter than the 2000s' average. The same applies for the previous 3-4 winters," he says.