Arctic tundra is becoming a source of carbon dioxide emissions, NOAA warns

Premonitory environmental milestones were abundant again this year in the Arcticwhere experts say dramatic climate changes are fundamentally altering the ecosystem and its functioning. A recent turning point for the region has to do with its carbon footprint: where conditions in the Arctic historically worked to reduce global emissions, they are now actively contributing to them.

This is a major transition that could have consequences for human, plant and animal life far beyond the northernmost part of the Earth, warned a group of scientists whose research appears in the National Oceanic and Atmospheric Administration report. Arctic Report Card 2024published on Tuesday. The report is an annual assessment of the polar environment, which in recent years has become a stark warning sign marked by sinister and unprecedented observations, all related to rising temperatures due to human-caused climate change. .

A central theme of the latest Arctic assessment was the effects of warmer climate and wildfires on the tundra, a far northern biome often known for its extreme cold, little precipitation and a layer of permanently frozen soil called permafrost. , which covers the earth. Those traits together made the Arctic a major carbon sink for millennia, meaning the region essentially helped reduce carbon dioxide emissions worldwide by absorbing more carbon than it emitted into the atmosphere.

This is mainly due to carbon uptake by plants, which regulate atmospheric levels of the molecule through photosynthesis, and a storage process in permafrost, which traps carbon dioxide in the soil. But rising air temperatures in the Arctic are breaking down permafrost across the tundra, in some cases severely. The Arctic report, for example, showed that Alaska permafrost temperatures in 2024 were the second warmest ever recorded. That causes the soil to warm up and thaw, and its carbon stores decompose along with it.

Research included in NOAA’s Arctic report shows that carbon that was once stored in tundra permafrost is actually being released into the atmosphere. In some parts of the region, this is happening at a rate that exceeds the carbon sink and instead creates a net increase in greenhouse gas emissions, something that is of particular concern to climate scientists at a time when that pollution from fossil fuel production has already increased. reached a record.

The same fossil fuels that overwhelm the atmosphere and prompt constant warnings from top United Nations weather and climate officials are fueling emissions in the Arctic, NOAA Administrator Rich Spinrad said in a statement about the new report’s findings.

“Our observations now show that the Arctic tundra, which is experiencing warming and increased wildfires, is now emitting more carbon than it stores, which will worsen the impacts of climate change,” Spinrad said. “This is one more sign, predicted by scientists, of the consequences of inadequate reduction in fossil fuel pollution.”

Forest fires in the Arctic They have been increasing at a rate never seen before, and that alone increases carbon emissions. The researchers suggest that 2024 had the second-highest recorded annual volume of wildfire emissions north of the Arctic Circle. Along with the release of carbon dioxide and methane gas from permafrost deposits, they say net emissions could continue to rise there. that climate change is warming faster than anywhere else on the planet.