A new study reveals that Arctic river deltas store roughly 58 billion tons of carbon in their frozen soils and sediments, an amount that has been missing from climate models. The research, published in Nature Communications, is the first comprehensive estimate of carbon and nitrogen stored in these remote regions. The deltas cover only 1% of permafrost land but hold 5% of its carbon, making them a potentially significant source of emissions if thawing accelerates. The study also found about 3.8 billion tons of nitrogen buried in the same deposits, which could fuel microbial activity and increase carbon dioxide and methane release as permafrost thaws. The Arctic is warming up to four times faster than the global average, and delta erosion is already visible in places like Alaska's Colville Delta, where frozen banks are crumbling at 3 to 13 feet per year. These findings could change how scientists forecast future warming.
