The Radiative controls of the Earth’s Hydrological Sensitivity

Abstract:

It is commonly stated that the hydrological cycle ‘intensifies’ under global warming. It has also been posited that this intensification is realized as an increase in global precipitation that is a slave to the availability of water determined by thermodynamically constrained increases of water vapor. This increase in global precipitation is referred to as the hydrological sensitivity of the climate system and it is only indirectly controlled by water vapor but through the latters influence on radiative fluxes. These radiative controls of the hydrological sensitivity are illustrated by analysis of CMIP5 data and the factors that determine the magnitude of the sensitivity are emphasized. The role of hemispheric differences in radiation balance on the hydrological sensitivity is also described.