Future changes in cyclone climatology over Europe as inferred from a regional climate simulation

This study analyzes the cyclone climatology of regional climate model simulations of present day (1961-1990) and future (2071-2100, A2 and B2 emission scenarios) european climate conditions. The model domain covers the area from Scandinavia to Northern Africa and from the Eastern Atlantic to Russia at a horizontal grid spacing of 50 km. Compared to present day, in the A2 and B2 scenario conditions the annual average synoptic variability increases over the North-East Atlantic and decreases over Russia and the Eastern Mediterranean region. This overall change pattern is larger in the A2 than in the B2 simulations. However, the cyclone climatology change signal shows a large intermonthly variability and important differences across European regions. The largest changes are found over the North-East Atlantic, where the synoptic variability and the intensity of extreme cyclones increase in winter and decrease in summer. A significant reduction of synoptic variability is found during late summer and autumn over the Mediterranean region, and from October to January over Russia. The number of cyclones decreases in future conditions throughout Europe, except over the central Europe and Mediterranean in summer (where it increases). The frequency of intense cyclones and the depth of extreme cyclones increases over North-East Atlantic, decreases over RUssia and show an irregular response to climate change throughout the rest of the domain.