This grant supports international scientists and graduate students to participate in a University of Pennsylvania Earth System Science Workshop on "The Global Water Cycle: Past, Present, and Future". The nature of the global water cycle and its role in global change has been singled out as a major problem area critical to an understanding of planetary change. The scientific approaches in this workshop involve atmospheric moisture transport and precipitation models, transfer between major reservoirs, the role of the hydrologic cycle in climate, the role of water in the world ecosystem, the water cycle coupled to biogeochemical cycles, hydroclimates of geologic history and associated phenomena, societal issues and a changing water cycle and the hydrologic cycle and future global change. Workshops in Earth System Science sponsored by the Earth System Science Center are directed to foster multidisciplinary interaction in the study of major problems in the sciences of the earth. This workshop is important because it treats broadly, the processes that control our planet's water cycle. This is a fundamental scientific problem that must be better understood in order to advance our knowledge of the earth's climate and its variability.
