Large changes in the Earth's hydrological cycle have been observed in the paleoclimate record and are projected to emerge as the climate warms. Expected responses to global warming include an enhancement of the climatological water cycle, the so-called "rich-get-richer" effect, and increases in global-mean precipitation of approximately 2% per degree of surface warming. However, on regional scales and over land, model simulations of future changes in the hydrological cycle remain highly uncertain. Challenges also remain in reconciling paleoclimate records of the hydrological cycle with theory and simulations. This points to a lack of understanding of the processes controlling the hydrological cycle, including changes in atmospheric circulation and clouds. The objective of this session is to advance our understanding of the large-scale hydrological cycle under past, current and future climate change. We encourage theoretical, observational, and modeling contributions on this topic.

Solicited talks: Pascale Braconnot, Debbie Polson, and Aiko Voigt