The atmospheric response to extratropical ocean warming induced by sea ice loss
Sea ice loss impacts the atmosphere by altering the surface energy balance, warming the Arctic lower troposphere, and potentially changing the large scale atmospheric circulation at mid-latitudes. A large number of studies have carried out numerical modeling experiments to isolate the atmospheric impacts of sea ice loss from other effects. These typically use an Atmospheric General Circulation Model (AGCM) forced with reduced sea ice concentrations while keeping sea surface temperatures and other forcings fixed. As the ocean cannot respond, these experiments ignore potentially important thermodynamic and dynamical feedbacks with the ocean. In this talk, I will examine the impact extratropical ocean warming caused by sea ice loss has on the atmosphere using both coupled ocean-atmosphere climate model and AGCM experiments. I will show that the extratropical ocean warming amplifies the atmospheric circulation response to sea ice loss, suggesting that previous studies using only AGCM experiments may underestimate the response.