LAUSR

Significance Topography change caused by melting ice in Arctic soils has the potential to accelerate permafrost thaw and trigger abrupt and large-scale change in the Arctic. We extended a site-scale permafrost thermal hydrology model to represent ground subsidence and combined it with new and existing data from a well-characterized tundra site to better understand the consequences of thaw subsidence in a warming Arctic. Our spatially resolved simulations of a representative carbon-rich tundra site indicate that subsidence will not accelerate permafrost thaw significantly and cause abrupt permafrost thaw over large areas. However, thaw subsidence will likely lead to more runoff and significantly accelerate drying of the tundra landscape in a warming climate with important effects on sensitive Arctic ecosystems.