WCR: Quantifying Fresh Water Fluxes, Runoff and Precipitation in the Global Water Cycle and Applying Them to Evaluate the Community Climate System Model (CCSM)

University Corporation For Atmospheric Res, Boulder CO

Investigators

Abstract

This Water Cycle Research (WCR) project seeks to determine the flux of water between various reservoirs, in order to quantify the global water cycle. The quantification is necessary for understanding the physical processes, characterization of hydroclimate variability and change, and for evaluation of climate models. Dai and co-PI Trenberth (both at NCAR) will strive to quantify the precipitation amounts, intensity and frequency, and evaporation, from atmospheric water budgets and fresh water discharges from the continents; global streamflow records from over 8000 stations will be analyzed. The results should improve understanding of the fundamental components of the water cycle, especially, runoff, river discharge, net surface water fluxes, and oceanic freshwater transport. The effort should lead to improved characterization of the interannual and decadal variabilities of the water fluxes, and of inter-basin transports. The PIs expect their efforts to advance climate model development since the major model deficiencies are related to aspects of the water cycle. The research should lead to improved modeling and prediction of hydroclimate variability and change, on both regional and continental scales. This work is of potential benefit to the broad community of climate scientists studying water cycle science in the context of climate change and variability. Moreover, the information from this research will improve climate models and their ability to project future climates, an important contribution to societal issues concerned with the environment.