DISPOSITION OF SOLAR-RADIATION IN SEA-ICE AND THE UPPER OCEAN

A one-dimensional sea ice model with an ice thickness distribution is presented to examine the disposition of the incoming surface shortwave radiation within the sea ice and the upper ocean. The sea ice model c onsists of 15 different ice thickness categories and an open water (le ads) category. Ice growth, melting on horizontal and vertical surfaces , meltwater pond growth and drainage, and snow accumulation evolve ind ependently for each of the ice categories. Leads, melt ponds, and thin ner ice categories are of particular interest, as these features accou nt for nearly all of the solar energy that is transmitted into the upp er ocean beneath the ice pack. Also examined is the surface reflection and absorption, internal ice absorption, and lateral melting for pond ed and pond-free ice. Area-averaged results show that 69% of the total annual solar energy is reflected, 15% is absorbed by the snow cover, 12% is absorbed by the ice, and 4% is transmitted to the ocean mixed l ayer through thin ice and leads.