Satellite-observed drop of Arctic sea ice growth in winter 2015–2016

Abstract

An anomalous warm winter 2015–2016 lead to the lowest winter ice extent and highlights the sensitivity of the Arctic sea ice. Here we use the 6 year record of an improved sea ice thickness product retrieved from data fusion of CryoSat-2 radar altimetry and Soil Moisture and Ocean Salinity radiometry measurements to examine the impact of recent temperature trend on the Arctic ice mass balance. Between November 2015 and March 2016, we find a consistent drop of cumulative freezing degree days across the Arctic, with a negative peak anomaly of about 1000 degree days in the Barents Sea, coinciding with an Arctic-wide average thinning of 10 cm in March with respect to the 6 year average. In particular, the loss of ice volume is associated with a significant decline of March first-year ice volume by 13%. This reveals that due to the loss of multiyear ice during previous years, the Arctic ice cover becomes more sensitive to climate anomalies.