Potential for extreme loss in high-latitude Earth surface processes due to climate change

Climatically driven Earth surface processes (ESPs) govern landscape and ecosystem dynamics in high-latitude regions. However, climate change is expected to alter ESP activity at yet uncertain rate and amplitude. We examined the sensitivity of key ESPs (cryoturbation, solifluction, nivation, and palsa mires) to changing climate by modeling their distribution in regard to climate, local topography, and soil variables in northern Fennoscandia. The distributions of ESPs were then forecasted under two future time periods, 2040-2069 and 2070-2099, using ensemble modeling and three emission scenarios. Increase of 2 degrees C in current temperature conditions caused an almost complete loss of ESPs, highlighting the extreme climatic sensitivity of high-latitude geomorphic processes. Forecasts based on three scenarios suggest a disappearance of suitable climate for studied ESPs by the end of this century. This could initiate multiple opposing feedback between land surface and atmosphere through changes in albedo, heat fluxes, and biogeochemical cycles.