Spread of Svalbard Glacier Mass Loss to Barents Sea Margins Revealed by CryoSat‐2

Abstract

The Norwegian Arctic archipelago of Svalbard is located in the most rapidly warming area of the Arctic, at the interface of Arctic and Atlantic air and ocean masses. The presence of a large number of surge‐type glaciers and the potential for rapid changes in surface mass balance and ice dynamics necessitates regularly updated mass balance assessment. This study uses swath processing of CryoSat‐2 SARIn mode data to obtain glacier elevations for 2011–2017. Individual elevation estimates are collected into 1‐km2 grid cells, and a least squares plane‐fitting technique is used to calculate rates of elevation change, with residuals being used to reveal the temporal pattern. A 7‐year rate of mass change of −16.0 ± 3.0 Gt a−1 is estimated (equivalent to 0.044 mm a−1 of global sea level rise), of which −11.0 Gt a−1 results from the melt and dynamic thinning of nonsurging ice and −5.0 Gt a−1 results from surges. This compares to ‐3.4 Gt a−1 previously estimated using ice, cloud, and land elevation satellite (ICESat) (2003–2008). The west coast remains a major contributor to mass loss from nonsurging ice in the archipelago, with mass loss increasing from areas bordering the Barents Sea. Sea ice concentration and climate reanalysis data sets show ocean and lower atmospheric warming and sea ice decline in this region, likely contributing to enhanced glacier melt and discharge.