The Rise of Atmospheric Evaporative Demand Is Increasing Flash Droughts in Spain During the Warm Season

Abstract

Flash droughts are characterized by rapid development and intensification, generating a new risk for drought impacts on natural and socio-economic systems. In the current climate change scenario, the meteorological drivers involved in triggering flash droughts are uncertain. We analyzed the role of meteorological drivers underlying the development of flash droughts in Spain over the last six decades, evidencing that the effect of atmospheric evaporative demand (AED) on flash drought is mainly restricted to water-limited regions and the warm season. However, the contribution of the AED has increased notably in recent years and particularly in summer (∼3.5% per decade), thus becoming a decisive driver in explaining the occurrence of the latest flash droughts in some regions of Spain. Our findings have strong implications for proper understanding of the recent spatiotemporal behavior of flash droughts in Spain and illustrate how this type of event can be related to global warming processes.