Coordinated Asia-European long-term Observing system of Qinghai – Tibet Plateau hydrometeorological processes and the Asian-monsoon systEm with Ground satellite Image data and numerical Simulations

Human life and the entire ecosystem of South East Asia depend upon the monsoon climate and its predictability. More than 40% of the earth's population lives in this region. Droughts and floods associated with the variability of rainfall frequently cause serious damage to ecosystems in these regions and, more importantly, injury and loss of human life. The headwater areas of seven major rivers in SE Asia, i.e. Yellow River, Yangtze, Mekong, Salween, Irrawaddy, Brahmaputra and Ganges, are located in the Tibetan Plateau. Estimates of the Plateau water balance rely on sparse and scarce observations that cannot provide the required accuracy, spatial density and temporal frequency. Fully integrated use of satellite and ground observations is necessary to support water resources management in SE Asia. To clarify the roles of the interactions between the land surface and the atmosphere over the Tibetan Plateau in the Asian monsoon system, a series of international efforts initiated in 1996 with the GAME-Tibet project. The effort described in this proposal builds upon 10 years of experimental and modeling research and the consortium includes many key-players and pioneers of this long term research initiative. The goal of this project is to: 1. Construct out of existing ground measurements and current / future satellites an observing system to determine and monitor the water yield of the Plateau, i.e. how much water is finally going into the seven major rivers of SE Asia; this requires estimating snowfall, rainfall, evapotranspiration and changes in soil moisture; 2. Monitor the evolution of snow, vegetation cover, surface wetness and surface fluxes and analyze the linkage with convective activity, (extreme) precipitation events and the Asian Monsoon; this aims at using monitoring of snow, vegetation and surface fluxes as a precursor of intense precipitation towards improving forecasts of (extreme) precipitations in SE Asia. The processes summarized above lead to identify the elements of a comprehensive system useful to observe timely the state of land surface over the Plateau, extract precursor information to improve forecast precipitation over the headwater areas of the Yellow River, Yangtze, Mekong, Salween, Irrawaddy, Brahmaputra and Ganga, monitor the water balance of the Plateau and its water yield, and assess the consequences of such forecasts in terms of floods and droughts, as well as contribute to establish an infrastructure for the Group on Earth Observations (GEO) water theme and capacity building in SE Asia.