Evaluation of Maize Crop Water Requirement Under Changing Climate over Konso, Southern Ethiopia

Abstract

Climate change has become a major concern and receiving serious attention at global, National, regional and local levels. The purpose of this study is to evaluate maize crop water requirement under climate change scenario in konso woreda, Southern Ethiopia. This was conducted based on near-term 2019-2048 projected climate variables from CORDEX-Africa data for RCP 4.5 and RCP 8.5 scenarios. The projected data was quality checked, biased corrected and model performance was evaluated. Mann Kendall trend detection and Sen’s slope estimator were used by XLSTATA software to evaluate the trends of projection and to detect changes. The Cropwat model was used to estimate crop water requirement of maize. Projected rainfall pattern shows decrease by 1.312mm/annual, 1.5mm/annual and 0.803 under RCP 2.6, RCP 4.5 and RCP 8.5 respectively. Maximum temperature projected to increase 0.004, 0.004 and 0.005̊C/annual for near term under RCP 2.6, RCP4.5 and RCP 8.5 scenarios respectively. Minimum temperature is projected to increase significantly along with calculated evapotranspiration from projected temperature under three Scenarios. Overall result of this research shows that adaptation measures and water harvesting technologies are mandatory and recommended for cropping season to have sustainable production to feed increasing population. Keywords: Climate change; Evapotranspiration; CROPWAT