Mission: to observe, understand and model the hydrological cycle and energy fluxes in the Earth's atmosphere and at the surface

The Global Energy and Water Cycle Experiment (GEWEX) leads the WCRP studies of the dynamics and thermodynamics of the atmosphere, the atmosphere's interactions with the Earth's surface (especially over land), and the global water cycle. The goal of GEWEX is to reproduce and predict by means of suitable models the variations of the global hydrological regime, its impact on atmospheric and surface dynamics, and variations in regional hydrological processes and water resources and their response to changes in the environment, such as the increase in greenhouse gases. GEWEX will provide an order of magnitude improvement in the ability to model global precipitation and evaporation, as well as accurately assess the feedback between atmospheric radiation, clouds, land use, and climate change. Detailed plans for Phase II of GEWEX are available in the GEWEX Roadmap.

GEWEX projects are organized into three focus areas designed to address the key elements of the global energy and water cycle: Radiation, Hydroclimate, and Modelling and Prediction. 

GEWEX has four primary global data projects: the International Satellite Cloud Climatology Project (ISCCP), the Global Aerosol Climatology Project (GACP), the Global Precipitation Climatology Project (GPCP) and the Surface Radiation Budget Project (SRB). The latter two are supported by surface data projects, the Global Precipitation Climatology Centre (GPCC under Climate and Environment, Climate Data Centres) and the Baseline Surface Radiation Network (BSRN), respectively. GEWEX data sets can be accessed through the GEWEX website.

Examples of GEWEX accomplishments:
> The African Monsoon Multidisciplinary Analysis (AMMA) project - jointly with WCRP-CLIVAR - which involves the capabilities of meteorological services in West Africa yields unique data sets that support the development of climate models.
> GEWEX has developed high-resolution next generation hydrologic land surface and regional climate models by improving parameterizations and applying them for experimental predictions.
> GEWEX has developed global data sets on clouds, radiation and other parameters that are invaluable in understanding and predicting global processes.
> Modelling studies have identified key land-surface processes & conditions that contribute most significantly to the predictability of precipitation.
> GEWEX is developing land data assimilation systems that will resolve land surface features at resolutions as small as 1 km.

International GEWEX Project Office
Silver Spring, Maryland, United States
E-mail: gewex@gewex.org
Web: http://www.gewex.org/igpo.html