Future projection of mean river discharge climatology for the Chao Phraya River basin
Adisorn Champathong1,2, Daisuke Komori2, Masashi Kiguchi2, Thada Sukhapunnaphan1,
Taikan Oki2 and Tosiyuki Nakaegawa3,2
1Office of Water Management and Hydrology, Royal Irrigation Department, Thailand
2Institute of Industrial Science, The University of Tokyo, Japan
3Climate Research Department, Meteorological Research Institute, Japan
Abstract:
We projected future river discharge in the Chao Phraya River basin and evaluated the uncertainty in future climate projections by using different resolutions and ensemble experiments of the Atmospheric General Circulation Model of the Meteorological Research Institute (MRI-AGCM). We also obtained estimates of precipitation, evaporation, runoff, and river discharge under climate conditions projected for the late 21st century. The results show that precipitation is projected to significantly increase in the future during April
to August, excluding May. The projected river discharge at Nakhon Sawan located in the central region shows a peak in September, a delay of one month after the maximum monthly mean precipitation. The estimated reduction in river discharge for January and February was robust based on all members of the 60-km mesh MRI-AGCM ensembles changing in the same direction as that of the 20-km mesh MRI-AGCM. The uncertainty assessment conducted in this study could lead to increased robustness in projected changes in mean river discharge in the late 21st century for this basin.
KEYWORDS future climate projection; Chao Phraya River basin; Thailand; AGCM; Global River flow model using TRIP (GRiveT)
Hydrological Research Letters 7(2), 36–41 (2013)
Published online in J-STAGE (www.jstage.jst.go.jp/browse/HRL). doi: 10.3178/HRL.7.36