Climate change impacts on water flux dynamics in Shingoda basin having agriculture and forest ecosystems: A comprehensive analysis

Abstract

An assessment of climate chnage and its impacts on water fluxes in the Shingoda basin of the Saurashtra region having 14% agriculture and 75% forest were made through analysis of time series (1951-2100) of bias corrected maximum/minimum temperature and rainfall (RCP4.5), rreference evapotranspiration (ETo), evapotranspiration (ETc) and runoff. Results showed significant climate changes in the basin, with day mean temperature rising from 24.4°C in the second half of the 20th century to 26.5°C and 27.9°C in the first and second half of the 21st century, respectively. During the first and second half of the 21st century, seasonal rainfall increased by 23.0% and 46.33%, and runoff rose by 46.78% and 86.40% compared to the second half of the 20th century. However, annual reference evapotranspiration (ETo) decreased by -1.41% and -6.5%, and crop evapotranspiration (ETc) decreased by -3.2% and -9.8% in the same periods. The analysis also revealed a deficit of -16.10% in downward water flux (rainfall) in the first half of the 20th century, followed by a surplus of 8.46% and 28.37% compared to the upward flux (ETc) in subsequent periods. The upward water flux deficit during 2nd half of 20th century were supported by evidence of depleted groundwater levels and seawater intrusion in the study area.