Fourth Study Conference on BALTEX Scala Cinema Gudhjem

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Activities of the GEWEX Hydrometeorology Panel (GHP)
J. Roads (GHP chair)
University of California, San Diego, 9500 Gilman Drive MC 0224, La Jolla, CA 92093-0224
During the past decade, the Global Energy and Water
Cycle Experiment (GEWEX), under the auspices of the
World Climate Research Program (WCRP), has
coordinated the activities of the Continental Scale
Experiments (CSEs) and other global land surface
research through the GEWEX Hydrometeorology Panel
(GHP). The GHP contributes to specific GEWEX
objectives such as "determining the hydrological cycle
and energy fluxes, modeling the global hydrological
cycle and its impact, developing a capability to predict
variations in global and regional hydrological processes
and fostering the development of observing techniques,
data management and assimilation systems." GHP
activities include diagnosis, simulation and prediction of
regional water balances by various process and modeling
studies aimed at understanding and predicting the
variability of the global water cycle, with an emphasis on
regional coupled land-atmosphere processes in different
climate regimes. This talk will provide an overview of
past, present and future GHP efforts to develop a water
and energy budget synthesis over the individual CSEs.
For example, during summer, atmospheric water vapor,
precipitation and evaporation as well as surface and
atmospheric radiative heating increase and the dry static
energy convergence decreases almost everywhere. We
can further distinguish differences between hydrologic
cycles in midlatitudes and monsoon regions. The
monsoon hydrologic cycle shows increased moisture
convergence, soil moisture, runoff, but decreased sensible
heating with increasing surface temperature. The
midlatitude hydrologic cycle, on the other hand, shows
decreased moisture convergence and surface water and
increased sensible heating.