Trends in European precipitation extremes over 1951-2010

摘要

Significant trends in precipitation extremes over Europe since the middle of the 20th century have been found in earlier studies. Most of these studies are based on descriptive indices of moderate extremes that occur on average a few times per year. Here we have analyzed rarer precipitation events which occur on average once in 5, 10 and 20years in the 1950s and 1960s using extreme value theory. We have focused on the 1-d and 5-d precipitation amounts in Northern and Southern Europe in all four seasons. Changes over the time period 1951-2010 are studied by considering five consecutive 20-year time intervals with 10-year overlap. Despite considerable decadal variability, our results indicate that 5-, 10- and 20-year events of 1-d and 5-d precipitation for the first 20-year period generally became more common during this 60-year period. For all regions, seasons and return periods, the median reduction in return period between the first and last 20-year periods is ~21% with variations between a decrease of ~2% and ~58%.