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Abstract

The Arctic surface is undergoing rapid changes due to the warming of the Earth’s atmosphere and oceans, including a reduction in perennial sea ice, creation of leads early in the spring, as well as the expansion of marginal ice zone and its fractured sea ice in late spring and summer. The changing surface can lead to modifications in Arctic meteorology, which can also then spread to lower latitudes. This study seeks to understand the role of the surface heterogeneity of ice/water patterns on surface-atmosphere coupling. Remote satellite observations (ice-water interface data, among others) are used as a bottom boundary condition for Large Eddy Simulations (LES) of air flow and associated heat transport to understand the non-linear surface-air exchanges. The strong thermal contrast between warm sea water and cold Arctic air/ice is shown to generate convective plumes and secondary circulations that enhance the transport of heat, humidity, and aerosols. The results suggest that surface heterogeneity of the ice-water-air interface acts as a significant driver of accelerated ice melting in the Arctic spring and summer. The long-term goal is to develop parametrizations for mesoscale and global models and enable them to resolve these microscale processes and feedbacks that are not currently resolved.