Assessment of Climate Change Impact on Hydrological Regime of Mahanadi River

Abstract

Climate change has a significant role on the available water resources. There is a large variability in the water availability in the Mahanadi basin. Therefore, there is a requirement to modify the present knowledge and methods in measures modification in water resources during this region. To analysis the climate change, CORDEX data of two RCMs at daily time step for two different climate RCP 4.5 and RCP 8.5 scenarios has been used which are respectively produced by IITM and SMHI. The Early century (2010-2039), Mid-century (2040-2069), and End century (2070-2099) with respect to Reference period (1973-2004) was used for climate data analysis under two climate scenarios. The result showed that each climate model showed variability in the projected climate. VIC hydrological model has been used for Normal long-term discharge simulation. Calibration and validation was done for two different periods. For future river discharge simulation, VIC calibrated model forced by climate model data was used to generate the runoff scenarios. The result show large change in simulated runoff under the future climate scenarios RCP 4.5 and RCP 8.5 respectively. The results obtained from this study showed surface runoff is more sensitive to the changes in surface temperature and precipitation. Moreover, it was found that the change in stream flow and surface runoff are more effected due to change in precipitation rather than air temperature.