moneyplay Arctic Tundra Has Long Helped Cool Earth. Now, It’s Fueling Warming.

For thousands of years, the shrubs, sedges, mosses and lichens of the Arctic have performed a vital task for the planet: gulping down carbon dioxide from the air and storing the carbon in their tissues. When the plants die, this carbon is entombed in the frigid soil, where it no longer helps warm Earth’s surface.

But as fossil fuel emissions heat the planet, balmier air temperatures are thawing Arctic tundra, activating carbon-hungry microbes, and more vegetation is being burned up by wildfires.

The result, for the past two decades or so, is that the tundra has been adding more carbon dioxide to the atmosphere than it has removed, a reversal from the usual state of affairs since the peak of the last ice age.

It’s one of many signs of rapid change in the National Oceanic and Atmospheric Administration’s Arctic Report Card, the agency’s yearly checkup on the polar region. The 2024 report card was issued on Tuesday in Washington at the annual meeting of the American Geophysical Union, an association of earth and space scientists.

For the 11th year in a row, the Arctic this year was more abnormally warm than the world as a whole, the report card said. The period from October 2023 to September was the second-warmest for the region since 1900. In the Northwest Passage, the sea route that links the Atlantic and the Pacific through the islands of northern Canada, the area covered by sea ice this summer was the lowest since records began. Parts of Arctic Canada had their shortest snow season on record.

“The Arctic today, year after year, looks vastly different than the Arctic did 20 years ago,” said Twila Moon, an editor of the report card and the deputy lead scientist at the National Snow and Ice Data Center in Boulder, Colo.

We are having trouble retrieving the article content.

Please enable JavaScript in your browser settings.

Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.

Thank you for your patience while we verify access.

Already a subscriber? Log in.

Want all of The Times? Subscribe.moneyplay

• Has
• moneyplay
• Long
• Arctic
• Tundra