Solar Partitioning in the Arctic Basin: the Role of Melt Ponds and Sea Ice Thickness

Synthesis of existing data has been carried out to assess the partitioning of solar heat across the Arctic basin over the satellite era. This assessment includes the effects of shortwave radiation reflected to the atmosphere, absorbed within the ice, and transmitted to the ocean and is computed daily on a 25 km x 25 km Equal-Area Scalable Earth Grid. Existing data sets used in the synthesis include: sea ice concentration obtained from passive microwave remote sensing using NASA Team algorithm of Maslanik and Stroeve and Cavalieri and others, downwelling incident shortwave radiation obtained from Modern Era Retrospective-Analysis for Research and Applications (MERRA), melt pond fraction obtained from visible remote sensing as made available by Rosel and others [2012], ice age computed by Tschudi and others, ice-type dependent seasonal albedo climatologies as put forth by Perovich and others [2002] and Perovich and Polashenski [2012], ice thickness obtained from Arctic regional modeling results using the PIOMAS model as described by Zhang and Rothrock [2003], and in-ice light extinction coefficients derived from the observational record as described by Light and others [2015]. The assembled data set is an informative tool for addressing many questions involving the ice-albedo feedback, in particular, the role of reduced ice concentration relative to enhanced melt pond coverage and the role of reduced ice thickness in ocean mixed layer heating.