Self‐Amplifying Feedbacks Accelerate Greening and Warming of the Arctic

Abstract

Increased greening, higher vegetation productivity, and shrubification have been observed in Arctic tundra in response to recent warming. Such changes have affected the near‐surface climate through opposing biogeophysical feedbacks (BF) associated with changes to albedo and evapotranspiration. However, the likely spatiotemporal variations of BF to future climate change and the consequences for Arctic vegetation and ecology have not been robustly quantified. We apply a regional Earth system model (RCA‐GUESS) interactively coupling atmospheric dynamics to land vegetation response in three potential 21st‐century radiative forcing simulations for the Arctic. We find that BF, dominated by albedo‐mediated warming in early spring and evapotranspiration‐mediated cooling in summer, have the potential to amplify or modulate local warming and enhance summer precipitation over land. The magnitude of these effects depends on radiative forcing and subsequent ecosystem responses. Thus, it is important to account for BF when assessing future Arctic climate change and its ecosystem impacts.