Assessment of Impact of Climate Change in the Western Ghats Region, India

Abstract

Objectives: The current research assessed the patterns of precipitation and discharge in the Sagar and Kokkarne catchments in the Western Ghats of Karnataka. Methods: Soil and Water Assessment Tool (SWAT) model was used to find the discharge at the outlets of the catchments. The yearly precipitation and discharge patterns of both the catchments were studied using data from observed data (1991 to 2020) and the projected data (2021-2050). Considering the IMD data (1991-2020) as the reference data, the percentage change in precipitation and discharge were calculated. Findings: For the Sagar catchment, the maximum percentage change in precipitation and discharge were projected to be 24.79 % and 53.71 %, and the minimum percentage change in precipitation and discharge were projected to be -20.29 % and -41.65 %. For the Kokkarne catchment, the maximum percentage change in precipitation and discharge were projected to be 31.30 % and 42.92 %, and the minimum percentage change in precipitation and discharge were projected to be -18.22 % and -16.98 %. In both the catchments, the increase or decrease in precipitation has led to corresponding changes in the discharge of the catchment. Novelty: This present work tries to project and compare the precipitation and discharge patterns in two catchments belonging to two varied river flow regimes in the Western Ghats of Karnataka to establish how the changing climate is affecting the hydrology of the catchments. As the precipitation varies in intensity throughout time and space and Indian agriculture relies heavily on precipitation, the present study can help in formulating water resource management techniques. Keywords: Western Ghats; Hydrological Cycle; IPCC; SWAT model; Lockdown; Vaccination