Analysis of Climate Variability and Its Impact on Crop Yield Over Waghemra Zone, Ethiopia

Abstract

Climate variability manifested by seasonal rainfall and temperature variability greatly affects agricultural crop production under rain-fed conditions (main source of income for rural communities). Therefore, this study has focused on analyzing the impacts of climate variability on rain-fed wheat and sorghum production in Waghemra Zone, Ethiopia. Daily rainfall and temperature data were collected from National Meteorological Agency of Ethiopia and crop yield data was collected from Central Statics Agency of Ethiopia. Temporal variability of rainfall, temperature and crop yield was analyzed using coefficient of variation (CV) and standardized anomaly method. The rainfall and temperature trends were assessed via Mann-Kendall test and Sen’s slope estimator. The impacts of climate variability on crop yields were evaluated using correlation and regression analysis. The rainfall analysis exhibited large inter-annual and seasonal variation both in amount and distribution. The rainfall has showed decreasing trends in Belg and increasing in both annual and Kiremt season. Moreover, the detected trends are not significant. In contrast, minimum and maximum temperature showed significantly increasing trends at annual and seasonal time scales. The number of warm days and nights has increased and the number of cold days and nights has decreased. The regression analysis revealed that climate variability over the study area has differential effects on the yield of Wheat and Sorghum with coefficient of determination 86% and 84%, respectively. The observed rainfall and temperature variability has posed major risks to rain-fed agriculture and specific adaptation strategies are needed to cope with the risks, sustain farming and improve food security.