Snow Depth on Sea Ice in the Changing Arctic

The Arctic has undergone dramatic changes in recent decades, the most prominent being the record sea ice loss during the 2012 summer season. The ice pack has shifted from thick, multiyear sea ice to a thinner, younger sea ice regime; it has become more dynamic and susceptible to changes in surface energy terms, such as snow cover, solar absorption, oceanic heat flux, and others. Though these terms are all intimately linked to each other, this study focuses primarily on snow cover because of its instrumental role in the growth and decay of Arctic sea ice. This study provides a current assessment of the snow cover on Arctic sea ice using IceBridge snow thickness data for 2009-2012. Spring snow cover has thinned by approximately 50% in the Beaufort and Chukchi seas and 20% in the Arctic Ocean compared to the 1954-1991 climatological record from Soviet drifting ice stations. The decrease in snow thickness is likely due to delayed sea ice freeze-up and changes in snowfall rates. These results may help us better understand the surface energy budget in the changing Arctic, and may improve our ability to predict the future state of the sea ice cover.