Scientists have discovered that carbon dioxide may be escaping from thawing permafrost in Antarctica, a phenomenon that has previously worried climatologists regarding the Arctic region.
Livio Ruggiero from Italy’s National Research Council and his colleagues conducted three field campaigns during the southern summers of 2020, 2023, and 2025. The team collected hundreds of measurements across the Taylor Valley, a freezing cold desert on the edge of the continent. To monitor the gases, the scientists drove small canisters into the ground at selected sites to determine the speed at which carbon dioxide seeped through the frozen soils.
In 2020, measurements showed an average of roughly 1.7 grams of CO2 creeping through 1 square metre of soil every day. By 2025, Ruggiero reported that this rate had grown five-and-a-half fold to 9.5 grams per day. Ruggiero stated, “We were really surprised,” and described the increase as "amazing" and "entirely unexpected." To confirm the findings, Ruggiero extracted gas samples from the field instruments and verified the concentrations using sophisticated equipment in a lab at their research station.
The 9.5 grams of CO2 per day is roughly equivalent to the amount of CO2 Arctic soils emit in the summer. However, while Arctic emissions often come from decomposing long-frozen flora, Antarctic gases appear to be seeping from ancient stores of CO2 mobilised by underground processes as warming alters the continent's hydrology.
Peter Morse at the Geological Survey of Canada called the findings "intriguing." While permafrost can act as a frozen lid on oil and gas reservoirs, Morse noted that the CO2 leak doesn’t appear to be driven by permafrost thaw, stating, “What is driving the rise is unclear.”
Ruggiero and his colleagues speculate that perhaps subglacial lakes in Antarctica’s interior, which have accumulated salt and carbon dioxide over aeons, could be discharging brines at a quicker pace as glaciers melt. They suggest this salt water may be thawing the permafrost from the bottom up, allowing subterranean stores of carbon dioxide to escape. The team intends to investigate this hypothesis in a future expedition.
Ida Kubiszewski at University College London, who led an interdisciplinary paper on global threats posed by Antarctic tipping points in 2024, identified permafrost as a threat. She stated, “But we don’t understand the processes enough, so this study is an important piece of the puzzle.”
Ruggiero’s team argues that climate scientists must begin to account for these processes in carbon budgets for the southern hemisphere. When scaling measurements to the total ice-free terrain in Antarctica, the team found that emissions could add up to 76.8 million tonnes of CO2 per year. This figure is comparable to Chile’s annual greenhouse gas emissions in 2024, which were 78.7 million tonnes. The team noted this estimate is by no means a rigorous inventory of Antarctica’s natural carbon emissions, but it reveals a potential significant source of carbon entering the atmosphere that has not yet been accounted for.
