Fourteenth International Conference on Climate Change: Impacts & Responses

Abstract

Drought is one of the most important environmental, social, and economic challenges. This study investigated the trend and temporal variation of drought for the period of 1981-2017 in East Wollega Zone, Western Ethiopia. The daily rainfall data of seven stations for 37 years (1981-2017) was collected from National Meteorological Agency of Ethiopia. The study utilized multi-index approach drought indexes such as Standardized Precipitation Index (SPI), Standardized Precipitation Evapotranspiration Index (SPEI), Rainfall Anomaly Index (RAI), Palmer Drought Severity Index (PDSI), Deciles Index (DI), Reconnaissance Drought Index (RDI), Percent Normal Precipitation Index (PNI), Z-Score (ZSI) and Precipitation Concentration Index (PCI) using R and DrinC software. The result of the study showed a declined trend of rainfall while the trend and frequency of drought increased. All the drought indices commonly indicated the area more affected by drought during the period of 1999-2005. The trend of annual rainfall deviation from normal was increased while it was decreased on seasonal bases. The temporal precipitation distribution of the area was moderate for 22 years (59.46%) and irregular rainfall distribution for 15 years (40.54%). Decisions regarding the cropping system and planning adaptation in the area are better to take into account the declining rainfall and in increased trend and frequency of drought.