Reply on RC2

Abstract

The inherently dry summer climate of the Iberian Peninsula (IP) is undergoing drought exacerbated by more intense warming and reduced precipitation. Although many studies have studied changes in summer climate factors, it is still unclear how the changes in moisture contribution from the source lead to the decrease in summer precipitation. This study investigates the differences in the IP precipitationshed between 1980–1997 and 1998–2019 using the Water Accounting Model-2layers with ERA5 data, and assesses the role of local recycling and external moisture in reducing summer precipitation. Our findings indicate that the moisture contributions from the local IP, and from the west and the east of the precipitationshed contributed 1.7, 3.6 and 1.1 mm mon−1 less precipitation after 1997 than before 1997, accounting for 26 %, 57 % and 17 % of the main source supply reduction, respectively. The significant downward trend of the IP local recycling closely links to the disappearance of the wet years after 1997 as well as the decrease of local contribution in the dry years. Moreover, the feedback between the weakened local moisture recycling and the drier land surface can exacerbate the local moisture scarcity and summer drought.