The changing ice cover of the Beaufort Sea and the impact of recent extreme events

Abstract:

The ice cover of the Beaufort Sea has undergone a notable change from a predominantly multiyear ice cover, that was resilient to melt and fostered the distribution of multiyear ice throughout the Arctic, to a primarily seasonal ice cover, that is more susceptible to breakup earlier during spring and melt rapidly during summer. This change began in 1998 but has been exacerbated lately, highlighted by complete summer regional sea ice-loss in September 2012 and 2016. Ice loss in 2016 was conditioned by ice export and divergence during winter that created a thinner end of winter ice cover that broke up early and melted rapidly. The following winter a predominantly seasonal ice cover formed throughout the beaufort, but the inherently thin ice cover was heavily deformed by ice import and convergence during the winter 2017 reversal of the Beaufort Gyre. Ultimately by the end of winter the seasonal ice cover of 2017 was the thickest and roughest ice cover within the CryoSat-2 record. Within this work we use a variety of remotely sensed and in situ observations to contrast these two conditioning processes and examine how winter conditioning influences summer melt in the Beaufort Sea.