Temporal Rainfall Anomaly and Its Association with Crop Yield: In the Case of Afar Region, Ethiopia

Abstract

Ethiopian economy is predominantly agrarian and the majority of the population in the country engaged in agricultural activities which is considerably affected by rainfall variability. The majority of the nation's crops are rain-fed, making them particularly vulnerable to the fluctuation that can cause severe food insecurity, which can result in famine and poverty over the whole nation. The impact of rainfall variability was very serious in the pastoral areas that are largely inhabited by the pastoralist whose livelihood depend primarily on livestock farming. For this study, rainfall data were taken from Ethiopian Meteorology Institute (EMI) for 1981-2020 period and yield data were taken from Central Statistical Agency (CSA) of Ethiopia for 1994-2019 period. This study was briefly evaluated rainfall variability and its impact on yield and computed Rainfall Anomaly Index (RAI) for Kiremt cropping season in a pastoral area of Afar region, Ethiopia. Regression analysis for the Kiremt cropping season based on observed rainfall dataset was used in the study to further analyze the relationship between rainfall variability and yield. The temporal analysis of RAI clearly indicated that there were more dry years than wet years with varies magnitude. The year of 1984 and 2009 were found extremely dry with magnitude of -4.95 and -4.13, respectively whereas 1987, 2015, 2002, 2004 and 1997 were identified as very dry with magnitude of -3.92, -3.39, -3.16, -2.88 and -2.41, respectively. The year of 1988 and 1998 found extremely humid with magnitude of 5.87 and 5.33 whereas 2020, 1994, 2010 and 1992 were very humid with magnitude of 3.47, 3.20, 2.98 and 2.34 respectively. The outcome of the regression analysis showed a positive link between rainfall anomaly and crop production for the Kiremt cropping season, with yield increasing with a positive rainfall anomaly and rainfall anomaly accounting for 29.4% of crop yield. Keywords: Kiremt Cropping Season, Rainfall Anomaly Index, Pastoral Area, Regression, Yield DOI: 10.7176/JEES/12-9-03 Publication date: September 30 th 2022