Abstract
Abstract. In this study we simulate the climatic mass balance of Svalbard glaciers with a coupled atmosphere–glacier model with 3 km grid spacing, from September 2003 to September 2013. We find a mean specific net mass balance of −257 mm w.e. yr−1, corresponding to a mean annual mass loss of about 8.7 Gt, with large interannual variability. Our results are compared with a comprehensive set of mass balance, meteorological, and satellite measurements. Model temperature biases of 0.19 and −1.9 °C are found at two glacier automatic weather station sites. Simulated climatic mass balance is mostly within about 100 mm w.e. yr−1 of stake measurements, and simulated winter accumulation at the Austfonna ice cap shows mean absolute errors of 47 and 67 mm w.e. yr−1 when compared to radar-derived values for the selected years 2004 and 2006. Comparison of modeled surface height changes from 2003 to 2008, and satellite altimetry reveals good agreement in both mean values and regional differences. The largest deviations from observations are found for winter accumulation at Hansbreen (up to around 1000 mm w.e. yr−1), a site where sub-grid topography and wind redistribution of snow are important factors. Comparison with simulations using 9 km grid spacing reveal considerable differences on regional and local scales. In addition, 3 km grid spacing allows for a much more detailed comparison with observations than what is possible with 9 km grid spacing. Further decreasing the grid spacing to 1 km appears to be less significant, although in general precipitation amounts increase with resolution. Altogether, the model compares well with observations and offers possibilities for studying glacier climatic mass balance on Svalbard both historically as well as based on climate projections.
Highlights
The Svalbard archipelago has a glacierized area of ca. 34 000 km2 (Nuth et al, 2013), representing ∼ 4 % of the world’s land-ice mass outside the Greenland and Antarctic ice sheets
To examine the importance of model resolution in this region we compare results from domains with 9 and 3 km grid spacing and, for a selected month, precipitation results from 9, 3, and 1 km grid spacing domains. Through this high-resolution simulation and extensive model evaluation, we aim to provide a detailed estimate of recent climatic mass balance (CMB) of Svalbard glaciers, including its spatial and temporal variations
We simulated the CMB of the Svalbard archipelago with a coupled atmosphere–glacier model, for the period 2003 to 2013 with 9 km and 3 km grid spacings, as well as with 1 km grid spacing for a shorter period
Summary
The Svalbard archipelago has a glacierized area of ca. 34 000 km (Nuth et al, 2013), representing ∼ 4 % of the world’s land-ice mass outside the Greenland and Antarctic ice sheets. The archipelago has already experienced significant warming during the 20th century (Førland et al, 2011) and, with the expected retreat of the sea ice margin, further warming as well as precipitation increases are expected (Day et al, 2012). Projections presented in the latest assessment report of the IPCC (AR5) shows that annual-mean temperatures in this region could rise between 7 and 11 ◦C by the end of the 21st century under the RPC8.5 scenario, accompanied by a projected precipitation increase between 20 and 50 % (IPCC, 2013). Svalbard glaciers are expected to undergo significant changes during this century (Day et al, 2012; Lang et al, 2015a). Reliable estimates of future glacier changes require modeling tools that are able to reproduce recent observations. Current model estimates based on global climate data sets (Marzeion et al, 2012, 2015)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
