ESTIMATING FUTURE CHANGES OF EXTREME RIVER DISCHARGE IN THE RED RIVER, VIETNAM USING d4PDF

Abstract

 Future changes in annual maximum river discharge in the Southeast Asia region were estimated using “database for Policy Decision making for Future climate change (d4PDF)” taking the Red River basin, Vietnam as a case study. A distributed Hydrologic Model 1K-DHM, based on a kinematic wave approximation, was used for rainfall-runoff simulation. In addition, future changes of the atmospheric environments resulting largest-class flood peak discharge were evaluated. The results show that 1) the frequency distributions of annual maximum 15-days rainfall for d4PDF of the historical experiment match with those for APHRO_MA. 2) In the return period of 10 years or more, a significant difference was detected in the probability distributions of the annual maximum discharge between the past and 4-degree rise experiments. 3) In the 4-degree rise experiment, the instability of a moist atmosphere increases, which may enhance the convergence of vertically integrated water vapor flux and thus, result in stronger precipitation.