Spatial variability of global lake evaporation regulated by vertical vapor pressure difference

Evaporation ( E ) from about 300 million lakes worldwide without plant physiological constraints directly reflects hydrological response to atmospheric forcings. However, it remains inadequately understood about what regulate spatial variability of global lake E across seasons. Here we show that vertical vapor pressure difference ( e D ) accounts for 66% of the spatial variability of annual E , followed by wind speed (16%). The e D is also the predominant factor modulating diurnal variability in E and causing greater E at night than during the daytime. As a consequence, spatial variability in nighttime E strongly regulates that in global E across seasons. Therefore, the observed widespread, heterogeneous changes in lake surface temperature that imply spatial variability in e D may have contributed to changes in global E variability.