For thousands of years, the Arctic tundra served as one of Earth’s most dependable carbon storage systems. That role is now unraveling at an alarming pace. Wildfires, fueled by a rapidly warming climate, are converting the tundra into a net source of carbon dioxide, according to the U.S. National Oceanic and Atmospheric Administration (NOAA).
The development is chronicled in NOAA’s 2024 Arctic Report Card, which underscores that surface air temperatures in the region this year climbed to their second-highest levels since recordkeeping began in 1900.
“The Arctic is now emitting more carbon than it sequesters, creating a feedback loop that amplifies global climate impacts,” NOAA Administrator Rick Spinrad remarked in response to the findings.
The Arctic is warming up to four times faster than the global average, a trend that has endured for over a decade. While warmer conditions initially spur plant growth, which helps extract carbon dioxide from the atmosphere, the thawing of permafrost negates the gains. As frozen soil melts, ancient organic material trapped beneath begins to decompose, releasing significant amounts of carbon dioxide and methane, two of the most potent greenhouse gases.
“We require a nuanced understanding of how much carbon the Arctic is discharging and absorbing to confront this crisis effectively,” said Dr. Sue Natali, a climate scientist at Woodwell.
High-latitude wildfires, intensified by human-driven climate change, are emerging as a powerful force behind the transformation. These fires, which are escalating in size, ferocity, and frequency, contribute to widespread carbon expulsion.
Burning vegetation and soil organic matter are only part of the issue. Fires also strip away insulating layers of soil, hastening permafrost thaw and the subsequent liberation of stored carbon.
“We’re starting to assess the cumulative effects of increased wildfire activity on Arctic carbon emissions, and the numbers are staggering,” explained Dr. Brendan Rogers, another contributor to the research.
Since 2003, wildfires across the Arctic have unleashed an average of 207 million tons of carbon each year, according to NOAA. Methane emissions from Arctic ecosystems have also remained a persistent concern, compounding the challenges posed by warming.
Brenda Ekwurzel, a climate scientist with the Union of Concerned Scientists, cautioned that the region’s shift from a carbon sink to a source could push ecosystems past irreversible tipping points.
“The Arctic’s transformation is not an isolated event—it’s a warning signal for the entire planet,” she said. “Once these systems cross critical thresholds, reversing the damage becomes nearly impossible.”
