Streamflow Forecasting in Chao Phraya River Basin by Ensemble Streamflow Prediction method

 

Wongnarin Kompor (Doctoral Course)

 

 Streamflow, water from the river, is crucial for all of the living life. A streamflow coming from the mountain and flow into the ocean through the river’s canal. The amount of water in the river increase by the precipitation. The precipitation regard as the most influential climate variable on the catchment water resources, and hydro climatic variables such as temperature, evaporation and soil moisture content influence the availability of water resources in a catchment. Recent decade, a phenomenon named “El Nino-Southern Oscillation (ENSO)” that can be seen over the eastern equatorial Pacific Ocean. ENSO is an anomalous oceanic-atmospheric circulation in terms of sea surface temperature (SST), and it has linked with changes in climate in the region.

 In Thailand, 2011, severe flooding occurred during monsoon season. The flooding began at the end of July by tropical storm. Theses floods spread through the province of northern, northeastern, and central part of Thailand along Chao Phraya river basin. In October, floodwaters reached the capital city of Thailand, Bangkok. Flooding remained in some areas until mid-January 2012. Sixty-five of Thailand’s seventy-six province were declared flood disaster zones, 815 deaths, 13.6 million people affected, and over 20,000 square kilometers of farmland was damaged.

 Since 2011, the importance of streamflow prediction have gradually become crucial to understand streamflow and support water management. Thus, understand and know how much of water increase or decrease for enough time will give a benefit to water management.

 

 In this study, a hydrological model, H08, has selected for streamflow simulation. H08 model is a distributed global water resources model (Hanasaki et al., 2008a). Three of six module, which contain land surface, river module and reservoir module, has selected in this study. An Ensemble Streamflow Prediction (ESP) method has applied with H08 model. An ensemble of climatic data, especially precipitation, has driven the possible results of streamflow. We expect that the outcomes from this study will provide a benefit information for water management in Thailand.

 

Schematic of H08 model

Streamflow simulation from 1982-2004