Topography and recent winter rainfall regime change in temperate Western European areas: a case study in the Rhine‐Meuse basin

Earlier trend analyses on rainfall series have clearly shown that the winter rainfall regime has changed since World War II over Northwestern Europe as a consequence of an enhanced westerly atmospheric circulation. However, few studies have been conducted on the potential link between the spatial variability of winter rainfall regime change and the topography. In the present study, a time series analysis of winter rainfall due to atmospheric westerly fluxes is performed and related to the topography of the middle Rhine‐Meuse area. The resulting geographical patterns show a zonal anisotropism of the winter rainfall regime change implying an intensification of horizontal rainfall gradients. More contrasted westerly winter rainfall amounts are observed in mountainous areas during the post‐1979 period following the changing‐point year of atmospheric circulation over Northwestern Europe. Copyright © 2006 Royal Meteorological Society.