Shifts in flood generation processes exacerbate regional flood anomalies in Europe

Abstract Anomalies in the frequency of river floods, i.e., flood-rich or -poor periods, cause biases flood risk estimates and thus make climate adaptation measures less efficient. While observations have recently confirmed presence anomalies Europe, their exact causes are not clear. Here we analyse streamflow during 1960-2010 to show that shifts generation processes contribute more occurrence regional than changes extreme rainfall. A shift from rain on dry soil wet events by 5% increased periods Atlantic region, an opposite Mediterranean region flood-poor but will likely singular floods occur often. Flood driven changing Europe may further intensify a warming should be considered estimation management.