2025 Arctic Sea Ice Reaches Record Low Maximum Extent

Scientists at the National Snow and Ice Data Center (NSIDC) have said that Arctic sea ice most likely reached its yearly maximum extent on March 22, at 5.53 million square miles.

The maximum sea ice extent for 2025 is the lowest in a satellite record going back 47 years, falling short of the last record low set in March of 2017.

“This new record low is yet another indicator of how Arctic sea ice has fundamentally changed from earlier decades,” said Walt Meier, NSIDC senior research scientist, in a press release from NSIDC. “But even more importantly than the record low is that this year adds yet another data point to the continuing long-term loss of Arctic sea ice in all seasons.”

Scientists from NSIDC stressed that the measurement of Arctic sea ice extent was preliminary. Weather conditions could alter the total maximum ice extent for the year. NSIDC’s full analysis will be issued in early April.

“In the dark and cold of winter, sea ice forms and spreads across Arctic seas. But in recent years, less new ice has been forming, and less multi-year ice has accumulated. This winter continued a downward trend scientists have observed over the past several decades. This year’s peak ice cover was 510,000 square miles (1.32 million square kilometers) below the average levels between 1981 and 2010,” a press release from NASA said.

Antarctic sea ice hit a near-record-low minimum extent on March 1, at 764,000 square miles, tying the second-lowest yearly minimum on record.

That’s 30 percent lower than the 1.1 million square miles of typical Antarctic sea ice extent prior to 2010. Sea ice extent is the total ocean area with a minimum of 15 percent ice concentration.

“Warming temperatures are what’s causing the ice to decline,” Meier said, as The Associated Press reported. “You know, sea ice in particular is very sensitive… 31 degrees is ice skating and 33 degrees it’s swimming.”

Reduced sea ice extent in both polar regions marked another milestone — the planet’s total sea ice has reached an all-time low. Ice coverage globally in mid-February was more than one million square miles below the average before 2010.

“We’re going to come into this next summer season with less ice to begin with,” said Linette Boisvert, a NASA ice scientist based at the Goddard Space Flight Center in Greenbelt, Maryland, in the NASA press release. “It doesn’t bode well for the future.”

The Arctic is warming at four times the rate of the rest of the planet, and it impacts weather all over the world, reported The Associated Press. As temperature and pressure differences shrink between north and south, the jet stream becomes weaker. This causes it to dip further south, bringing storms and cold temperatures that frequently get stuck, dumping more rain and snow.

“The warming winter atmosphere above the Arctic Circle does impact large-scale weather patterns that do influence those of us outside the Arctic,” said Julienne Stroeve, a University of Manitoba ice scientist.

Ice scientists mostly rely on measurements of Earth’s microwave range radiation by the Defense Meteorological Satellite Program. The natural radiation is distinct for sea ice and open water, with ice cover appearing bright on satellite images.

“It’s not yet clear whether the Southern Hemisphere has entered a new norm with perennially low ice or if the Antarctic is in a passing phase that will revert to prior levels in the years to come,” Meier said.