The Arctic has endured a year of record heat and diminishing sea ice as the world’s northern latitudes continue their rapid shift toward becoming wetter and less frozen due to the climate crisis, scientists reported.
From October 2024 to September 2025, temperatures across the entire Arctic region were the warmest in 125 years of modern record keeping, NOAA said, with the past 10 years being the 10 warmest on record in the Arctic.
The Arctic is warming up to four times faster than the global average, due to the burning of fossil fuels, and this extra heat is warping the global refrigerator, a region that acts as a key climate regulator for the rest of the planet.
The maximum sea ice extent in 2025 was the lowest in 47 years of satellite records, NOAA reported in its annual Arctic report. It’s the latest milestone in a longer trend, with the region’s oldest and thickest ice having shrunk by more than 95% since the 1980s as the Arctic becomes warmer and rainier.
This year has been a record-breaking year for precipitation in the Arctic. Much of this is not deposited as snow: the extent of June snow cover across the Arctic today is half what it was six decades ago.
“This year was the warmest on record and had the most precipitation — to see those two things happen in a single year is remarkable,” said Matthew Langdon Druckenmiller, an Arctic scientist at the University of Colorado National Snow and Ice Data Center and editor of the Arctic Report Card. “This year has really highlighted what lies ahead. »
Scientists have been struck by how the exceptional warmth of other seasons, particularly summer, is now also showing up in winter, affecting the annual growth of sea ice in the Arctic during the colder months. Over the past month, sea ice extent has been the lowest on record, which could herald further maximum sea ice reduction next year.
“There has been a steady decline in sea ice and unfortunately we are now seeing rain even in winter,” Druckenmiller said. “We’re seeing changes in the depths of winter, when we expect the Arctic to be cold. The very concept of winter is being redefined in the Arctic.”
These changes are deeply felt by humans and Arctic wildlife: rain falling on snow can freeze and form a barrier that makes it more difficult for animals to find food, while creating slipperier and more dangerous conditions for people traveling by road. Retreating glaciers can also cause potentially dangerous flooding, as was the case in Juneau, Alaska, this year.
The loss of sea ice opens up vast areas of dark ocean, which absorb, rather than reflect, more of the heat that drives global temperatures higher. While melting sea ice does not in itself cause rising seas, the loss of land-based glaciers does, with NOAA reporting that Greenland’s massive ice sheet lost 129 billion tons of ice in 2025. This will add to sea level rise that will threaten coastal cities for generations to come.
“We’re seeing cascading impacts of Arctic warming,” said Zack Labe, a climatologist at Climate Central. “Coastal cities are not prepared to cope with rising sea levels. We have completely changed fishing in the Arctic, which is leading to higher seafood bills. We may think of the Arctic as a faraway place, but the changes there affect the rest of the world.”
—Olivier MilmanThe Guardian
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