DPRI Newsletter International Cooperative Study
GEWEX Asian Monsoon Experiment


In order to clarify the impact of land surface-atmosphere interaction on the global climate system, an international research program GAME (GEWEX Asian Monsoon Experiment) was initiated in 1997.1998 was the key year in which intensive observation was carried out at three major observational regions, Huaihe, Tibet and Tropics. The hydrologists and meteorologists of DPRI took part in these three observational campaign.
The hydrologists of the Water Resources Research Center participated in the observation in the Huaihe river basin.(HUBEX) collaborating with staffs at the Huaihe River Commision (HRC). They set up one automated weather station(GAME-PAM) at Shouxian Meteorological Bureau and started observation from 14th August, 1998. They also conducted intensive flux observation at four sites with different landscape in the Shi-Guan river basin by using the flux observation system of Kyoto University (KU-AWS). The selected sites are forest, farmland, paddy field and water body. KU-AWS can collect many items such as 4 components of radiation, profiles of wind, air temperature, humidity and soil temperature, and turbulent flux. To get the data from different land condition, the KU-AWS was installed and removed from place to place during the observation period. This kind of moving observation was conducted in three seasons.
As for hydrological data, they installed two water gauges at Jiangi and Liji station. During the GAME-IOP several flood events were recorded by these instruments in 10 minute interval.
Hydrological data are also collected by HRC, which can be used according to an agreement.
Modeling studies are also conducted. The LSP (SiBUC) developed by WRRC is being tested with the GAME-IOP flux data. A mesoscale land-atmosphere coupled model (JSM88-SiBUC) was developed and used to understand the interaction between land surface processes and mesoscale cloud system.
The meteorologists of the Division of Atmospheric Disaster participated in the observation on the Tibetan Plateau collaborating with scientists at the Lanzhou Institute of Plateau Atmospheric Physics and the Lanzhou Institute of Glaciology and Geocryology of Chine-se Academy of Sciences. They set up four automated weather stations (AWSs), a fourteen meter meteorological tower, and the radiation observation sensors. The AWSs have successfully been collecting data since August 1997 and the others since May 1998. These automated observations have provided the continuous data of atmospheric temperature, humidity, wind, land surface temperature, soil temperature, radiation budget, precipitation and other hydrological and meteorological variables, which are valuable scientific data over the data sparse region of Tibetan Plateau.
A turbulence measurement system was operated during the Intensive Observation Period (May to September, 1998). More than 4000 Runs of turbulence data for temperature, three-dimensional wind and humidity were obtained, with which important parameters of land surface-atmosphere interaction, such as drag coefficient, sensible heat flux and latent heat flux are computed. These data are to be used to clarify the land surface-atmosphere processes and to establish its numerical model.
A PhD student of the Division of Atmospheric Disaster also participated in the aerological observation in Thailand. He also analyzes the GMS infrared Data over the tropical region.
The GAME Project will be continues at least another three years. On the Tibetan Plateau the automated observations are to be continued for several years. In the Huaihe region another intensive observation are planed in 1999.

Intensive Flux observation on the water body. PBL tower at Amdo, Tibetan Autonomous Region.