Arctic sea ice hits record-low winter maximum

Record Winter Low

Arctic sea ice reached its lowest winter maximum ever recorded this year, statistically tying last year's record low, according to the U.S. National Snow and Ice Data Center in Boulder, Colorado.

The annual maximum was reached on March 15, about a week earlier than last year. Sea ice extent measured 14.29 million square kilometers, just below last year's 14.31 million square kilometers, a difference the center described as a statistical tie.

It is the lowest level observed in 48 years of satellite monitoring. Previous record lows were also set in 2016, 2017 and 2018.

Climate Impact

Arctic sea ice forms when seawater freezes during the winter and partially melts in summer. But the amount that reforms each winter has been declining as rising temperatures linked to climate change disproportionately affect the Arctic.

NSIDC senior researcher Walt Meier said the weak ice formation gives a head start to the spring and summer melt season. Samantha Burgess of the European Centre for Medium-Range Weather Forecasts said the low maximum could lead to a potentially faster and more extensive summer melt.

The weak growth had been visible on satellite images for weeks and had already been reported earlier in March.

Risks Beyond Sea Level

Unlike glaciers and ice sheets on land, melting sea ice does not directly raise sea levels. But it can still have broad climate effects that threaten ecosystems.

Many species depend on sea ice for breeding and feeding, including polar bears in the Arctic and emperor penguins in Antarctica. Scientists also warned of wider knock-on effects. Gilles Garric, a polar oceanographer at Mercator Ocean Toulouse, said some areas in the Beaufort Sea near Canada and in the Siberian seas had never previously been exposed to the atmosphere, and that exposure could help warm those waters in summer.

The melting also carries geopolitical consequences by opening new shipping routes and improving access to mineral resources. Elizabeth Chalecki, an expert on climate change and security, said climate change-driven sea ice loss is turning the Arctic into a shared maritime space surrounded by competing states.