"Albedo evolution of seasonal Arctic sea ice," by Donald K. Perovich & Christopher Polashenski, GRL 39 (2012); doi:10.1029/2012GL051432

Geophysical Research Letters 39 (2012) L08501; doi:10.1029/2012GL051432

Albedo evolution of seasonal Arctic sea ice

Donald K. Perovich (CRREL, ERDC, and Thayer School of Engineering, Dartmouth College, Hanover, NH, U.S.A.) and Christopher Polashenski (CRREL, ERDC, Hanover, NH, U.S.A.)

Abstract

There is an ongoing shift in the Arctic sea ice cover from multiyear ice to seasonal ice. Here we examine the impact of this shift on sea ice albedo. Our analysis of observations from four years of field experiments indicates that seasonal ice undergoes an albedo evolution with seven phases; cold snow, melting snow, pond formation, pond drainage, pond evolution, open water, and freezeup. Once surface ice melt begins, seasonal ice albedos are consistently less than albedos for multiyear ice resulting in more solar heat absorbed in the ice and transmitted to the ocean. The shift from a multiyear to seasonal ice cover has significant implications for the heat and mass budget of the ice and for primary productivity in the upper ocean. There will be enhanced melting of the ice cover and an increase in the amount of sunlight available in the upper ocean.

Key points:

• During the melt season the albedo of seasonal ice is less than multiyear
• Seasonal ice absorbs and transmits more sunlight to ocean than multiyear
• Albedo evolution of seasonal sea ice has 7 phases