ASSESSMENT OF HYDRO-CLIMATOLOGY DROUGHT UNDER THE IMPACT OF CLIMATE CHANGE: A CASE STUDY IN THE SREPOK WATERSHED, VIETNAM

摘要

In recent years, the frequency of droughts that are due to climate change has increased around the world as well as in Vietnam and is accompanied by a rise in the severity of the phenomena. Understanding the characteristics of historical hydro-meteorological drought will benefit water resource managers because it will reveal the possible impacts of future climate change on drought, and subsequently, the availability of water resources. The objective of this study is to construct the past drought conditions and predict future drought scenarios for the Srepok watershed using two drought indices, i.e., standardized precipitation index (SPI) and streamflow drought index (SDI). Monthly climate data from the observational period 1980-2009 and over the projection period 2010-2099 from ensemble of four GCMs (CGCM3.1 (T63), CM2.0, CM2.1 and HadCM3) for A1B and B1 emission scenarios are used to calculate the duration, severity, and extent of meteorological droughts. Besides that, runoff data from the well-calibrated SWAT (Soil and Water Assessment Tool) hydrological model are used to examine the drought from a hydrological perspective. The impacts of climate change on the hydro-meteorological drought are assessed by comparing the present and the future drought. The results show that more severe droughts are predicted to increase in the future for the study area.