As Arctic sea ice has shrunk and thinned, so has the snowpack blanketing it.

Credit: Chris Linder/UW

Melinda Webster at the University of Washington in Seattle and her colleagues studied data on spring snow depth gathered between 2009 and 2013 by radar surveys conducted from the air and verified with surface measurements (pictured). They compared these to information collected between 1954 and 1991 by Soviet ice stations. The error bars are large, but between the older and the current surveys, snow thickness had decreased by some 37% in the western Arctic and by 56% in the Beaufort and Chukchi seas.

As sea ice starts forming later each autumn, there is less time for snow to accumulate before winter sets in, the authors say.

J. Geophys. Res. Oceans http://doi.org/t3q (2014)