Ice loss induced by wind-induced anomalous heat storage in the Antarctic seasonal ice zone

Edward Doddridge, Massachusetts Institute of Technology, Earth, Atmospheric and Planetary Sciences, Cambridge, MA, United States, John C Marshall, MIT, Cambridge, United States, Jean-Michel Campin, M.I.T./EAPS, Cambridge, United States and Maxwell Kelley, NASA Goddard Institute for Space Studies, New York City, United States
Stronger summertime westerly winds lead to anomalously cold sea surface temperature in the following weeks and months. Here we present a mechanism by which these winds can also cause anomalously warm wintertime sea surface temperatures and a reduction in the maximum wintertime sea ice extent. Strong summertime winds lead to enhanced vertical mixing, which draws heat downwards from the warmer surface waters. At the same time, anomalous atmospheric heat fluxes act to damp the cold sea surface temperature anomalies, drawing additional heat into the ocean. As the mixed layer deepens during the autumn months, the subsurface heat anomalies are brought back to the surface, leading to anomalously warm sea surface temperatures and reduced sea ice extents. Using a combination of observations and models we assess this mechanism in a zonally averaged context, and speculate about its importance regionally.