The Global Soil Wetness Project was started to shed lights on the hydrological processes on the continental scale and their impacts on the general circulation of the atmosphere.
At the Intercomparison Center, soil wetness index (SWI), snow depth and the basin-scale energy and water budget etc. were intercompared and validated against available observations. The working ranges of the normalized SWI was quite different among participating LSPs, although differences in the evapotranspiration and sensible heat flux were less. This raises a never-ending discussion on how soil moisture should be intercompared and validated against observations, and on what the spatially averaged soil moisture means.
The intercomarison between simulated fields in 1987 and 1988 showed marked interannual variabilities in many regions, say, mid-West U.S. and Indian monsoon area. The GSWP-II is planned to start from '99 and it will cover the ten years 1986-1995. The thrusts of the GSWP-II are the matters to be discussed among the participants, however the main thrust should be the investigation on the interannual variability of the land surface processes and its impact on the anomalous atmospheric circulation. Coodinations between LSP and GCM modellers (or groups) are desirable from the start of the planning of the project.
In Japan, an international workshop on "Hydrological Processes Over Land" is planned in February '99 and a research project on the same isuue is being proposed for the years starting from '99. The WS and the project is expected to make a contribution and give a thrust to the activities of GSWP-II