Severe summertime flooding in Europe

摘要

Using a high-resolution climate model, we are able to quantify the influence of greenhouse-gas-induced global warming upon heavy or extended precipitation episodes that inflict catastrophic flooding. We find that an increase in the amount of precipitation that exceeds the 95th percentile is very likely in many areas of Europe, despite a possible reduction in average summer precipitation over a substantial part of the continent. Our results indicate that episodes of severe flooding may become more frequent, despite a general trend towards drier summer conditions. In the European Union project PRUDENCE (EVK2-CT-2001-00132; ref. 1), the high-resolution (50-km grid) regional climate model HIRHAM4 (ref. 2) created by the Danish Meteorological Institute has been applied to two of the emission scenarios, A2 and B2, drawn up by the Intergovernmental Panel on Climate Change (IPCC). Three 30-year time-slice experiments were carried out for periods representing roughly the present (1961―90) and two future scenarios (2071―2100), respectively. The large-scale controlling conditions originated from transient climate-change simulations using the coupled ocean―atmosphere global climate model (OAGCM) ECHAM4/OPYC (300-km grid; refs 4, 5).