Altitudinal dependence of projected changes in occurrence of extreme events in the Great Alpine Region

Climate change has a strong impact on the environment in mountain areas, where ecosystems have adapted to climatic conditions that change with elevation. In this study, the response of temperature and precipitation climatic indices in the complex orography setting of the Great Alpine Region is discussed. The high-resolution gridded dataset that is presented has been produced with the Weather Research Forecasting (WRF) convection permitting regional model. Two 30-year periods have been considered (1979–2008, 2039–2068), obtained by downscaling global climate simulations with historical setting and RCP8.5 emission scenario. Both daily temperature and precipitation statistics have been found to be significantly different in the two periods, consisting in an overall projected warming and drying of the region. The dependence of the projected changes on elevation is highlighted, indicating a larger warming at medium and high elevations as well as a limited or nonexisting drying at high elevations. Physical mechanisms at the base of those differences are presented and discussed.