Relative roles of the Arctic and Antarctic sea ice melt on Indian summer monsoon

Abstract

The response of low-latitude weather and climate to polar sea ice melt is not well understood. In this study, we run a suite of fully coupled simulations using the Community Earth System Model to investigate the effects of polar sea ice melt on Indian summer monsoon (ISM). In the coupled model simulation, the albedo of the sea ice is reduced in such a way that the increased absorption of the solar radiation would melt the sea ice. The effects of the Arctic and Antarctic sea ice melts on the ISM have been examined. The findings reveal that the combined melting of sea ice in the Arctic and Antarctic exerts a stronger influence on the ISM compared to the melting at a single pole. Specifically, the ISM exhibits a relatively weak sensitivity to the Arctic sea ice melt, while showing a stronger response to sea ice melt over the Antarctic and the combined melt over both poles. The response of summer monsoon to sea ice melt is characterized by a weakening of the circulation and a decrease in the continental precipitation, indicating an overall weakening of the monsoon system as a result of the polar sea ice melt. The intertropical convergence zone (ITCZ) and associated precipitation pattern shift equatorward in the sea ice melt experiments.