Stable climate and surface mass balance in Svalbard over 1979–2013 despite the Arctic warming

Abstract. With the help of the regional climate model MAR (Modèle Atmosphérique Régional) forced by the ERA-Interim reanalysis (MAR_ERA) and the MIROC5 (Model for Interdisciplinary Research on Climate) global model (MAR_MIROC5) from the CMIP5 (Coupled Model Intercomparison Project) database, we have modelled the climate and surface mass balance of Svalbard at a 10 km resolution over 1979–2013. The integrated total surface mass balance (SMB) over Svalbard modelled by MAR_ERA is negative (−1.6 Gt yr⁻¹) with a large interannual variability (7.1 Gt) but, unlike over Greenland, there has been no acceleration of the surface melt over the past 35 years because of the recent change in atmospheric circulation bringing northwesterly flows in summer over Svalbard, contrasting the recent observed Arctic warming. However, in 2013, the atmospheric circulation changed to a south–southwesterly flow over Svalbard causing record melt, SMB (−20.4 Gt yr⁻¹) and summer temperature. MIROC5 is significantly colder than ERA-Interim over 1980–2005 but MAR_MIROC5 is able to improve the near-surface MIROC5 results by simulating not significant SMB differences with MAR_ERA over 1980–2005. On the other hand, MIROC5 does not represent the recent atmospheric circulation shift in summer and induces in MAR_MIROC5 a significant trend of decreasing SMB (−0.6 Gt yr⁻²) over 1980–2005.