Impacts of Antarctic summer sea-ice extremes

Abstract

Antarctic sea ice plays many crucial roles in the physical environments and ecosystems of Antarctica and the Southern Ocean. In this study, we synthesize the physical, biogeochemical, ecosystem, and societal impacts of summers with extreme low Antarctic sea-ice coverage. These extreme events result in the loss of multiyear landfast ice and changes in sea-ice seasonality. Following extreme low sea-ice events, we find surface warming of the Southern Ocean and changes to the formation rate of Antarctic Intermediate Water, likely affecting heat and carbon uptake. Ice-shelf calving is negatively correlated with sea-ice area, so that years with less sea ice show increased calving. Prolonged open w..