Simulating the Climatic Mass Balance of Svalbard Glaciers from 2003 to 2014 Using a Coupled Atmosphere and Climatic Mass-Balance Model

As a result of increasing air temperatures over the past few decades, the glaciers of the Svalbard archipelago show generally negative climatic mass balance (CMB). There are, however, large temporal and spatial variations in the CMB in this region, due to interannual changes in winter snow accumulation and summer melt. Previous mass-balance modelling efforts have mainly focused on individual glaciers or ice caps, with atmospheric forcing data obtained from either point measurements or coarse-resolution reanalyses. Here we present an 11-year simulation of the climatic mass balance of all Svalbard glaciers, performed with the coupled atmosphere and glacier model, WRF-CMB. The atmospheric component is the Weather Research and Forecasting model (WRF), which is used to dynamically downscale ERA-Interim reanalysis data to a resolution of 3 km for direct forcing of the simulation of glaciated grid cells by the CMB model. The results are evaluated with in situ mass-balance and meteorological observations from Austfonna, Northeast Svalbard, which covers an area of ~8000 km²and is the largest ice cap in the archipelago, as well as from glaciers in the Ny-Ålesund region, western Svalbard.