EVALUATING POTENTIAL IMPACT OF CLIMATE CHANGE ON HYDROLOGICAL VARIABLES IN UPPER GODAVARI RIVER SUB BASIN, INDIA USING SWAT

Throughout the world, climate change impacts are the main concern for sustainability of water management and water use activities. Climate changes alter regional hydrologic conditions and results in a variety of impacts on water resource systems. The goal of this study is to investigate the potential impact of climate change on runoff generation at upper Godavari River sub-basin watershed located in Maharashtra State, India. The GCM derived scenarios (HadCM3 A2 & B2, SRES emission scenarios) were used for the climate projection. The statistical Downscaling Model (SDSM) was used to generate future possible local meteorological variables in the study area. Downscaled and projected precipitation and temperature variables were used to simulate runoff for current and future climate scenarios using the Soil and Water Assessment Tool (SWAT) model. The time series generated by GCM of HadCM3, A2 and B2 and Statistical Downscaling Model (SDSM) indicate a significant increasing trend in maximum and minimum temperature values and a slight decreasing trend in precipitation for both A2 and B2 emission scenarios in sub-basin for all three bench mark periods (2020s, 2050s and 2080s). The result shows overall decreasing trend in annual and monthly runoff in the study area, in three benchmark periods in the future. The results of this work would be of great benefit to the design of economic and social development planning in the study area.