Climate of the Past Discussions www.clim-past-discuss.net 1814-9340 1814-9359 2 2 2006 10.5194/cpd-2-157-2006 http://www.clim-past-discuss.net/2/157/2006/ http://www.clim-past-discuss.net/2/157/2006/cpd-2-157-2006.html http://www.clim-past-discuss.net/2/157/2006/cpd-2-157-2006.pdf 157 189 2006-04-24 On the variability of return periods of European winter precipitation extremes over the last five centuries A. Pauling H. Paeth Institute of Geography, University of Bern, Hallerstrasse 12, 3012 Bern, Switzerland Meteorological Institute, University of Bonn, Auf dem Hügel 20, 53121 Bonn, Germany We investigate the changes of extreme European winter (December–February) precipitation over the last half millennium and show for various European regions that return periods of extremely wet and dry winters are subject to significant changes both before and after the onset of anthropogenic influences. Additionally, we examine the spatial pattern of the changes of the extremes covering the last 300 years where data quality is sufficient. Over central and eastern Europe dry winters occurred more frequently during the 18th and the second part of the 19th century relative to 1951–2000. Dry winters were less frequent during both the 18th and 19th century over the British Isles and the Mediterranean. Wet winters have been less abundant during the last three centuries compared to 1951–2000 except during the early 18th century in central Europe. Although winter precipitation extremes are affected by climate change, no obvious connection of these changes was found to solar, volcanic or anthropogenic forcing. However, physically meaningful interpretation with atmospheric circulation changes was possible.