A first of its kind study led by geoscientist Michael Rawlins at the University of Massachusetts Amherst has mapped in unprecedented kilometer level detail what is happening as a Wisconsin sized section of Alaska’s North Slope thaws across 44 years of model data from 1980 to 2023. The research reveals that runoff from hundreds of rivers and streams draining into the Beaufort Sea is increasing sharply as the Arctic active layer deepens each year and now stays unfrozen well into September and October, weeks longer than historical norms. The dissolved organic carbon locked in that permafrost for tens of thousands of years is now washing into Arctic rivers and ultimately into the ocean at accelerating rates, with more than 275 million tons of carbon released as carbon dioxide every year from the Arctic Ocean alone.

The carbon feedback loop is the most alarming mechanism the study describes. As the active permafrost layer deepens it unlocks ancient organic material that decomposes and releases CO2, which warms the atmosphere further, which deepens the active layer more. The northwest Alaska region is experiencing the largest DOC export increases because its flat terrain accumulated vast stores of decaying organic matter over millennia that are now mobilizing quickly, while the more mountainous eastern stretches have rockier soils that limit how much carbon dissolves into runoff. These are not modern organic compounds from recent vegetation but ancient carbon that has been frozen since the last ice age, effectively reintroducing prehistoric carbon stores into a climate system that has no natural mechanism to reabsorb them on any human timescale.

The ocean impacts are compounding on top of the atmospheric ones. Arctic rivers deliver 11 percent of the world’s total river water into an ocean that contains only 1 percent of global ocean volume, making the Beaufort Sea disproportionately sensitive to every change happening upstream on land. The influx of freshwater and dissolved carbon is already altering coastal salinity, shifting food web dynamics, and changing biogeochemical cycles in ways that researchers say are only beginning to be understood. Rawlins and his team are now modeling how ice wedge polygon thaw, ubiquitous across the high Arctic, is further intensifying the land to ocean carbon pipeline, and say the data is urgently needed for a global community that still has large gaps in its understanding of how much permafrost carbon ultimately reaches the sea.

EXCLUSIVE: A Wisconsin-Sized Chunk Of Alaskan Permafrost Is Thawing And Releasing Ancient Carbon Into The Ocean. Scientists Say The Climate May Never Fully Recover ⛈️🌞