Spatio-Temporal Characteristics of Meteorological Drought Under Changing Climate in Semi-Arid Region of Northern Ethiopia

Abstract Background: Below-normal availability of water for a considerable period of time induces occurrence of drought. This paper investigates the characteristics of meteorological drought under changing climate. The meteorological drought was assessed using the Standardized Precipitation Index (SPI) and the Reconnaissance Drought Index (RDI). The climate change was also analyzed using delta based statistical downscaling approach of RCP 4.5 and RCP 8.5 in R software packages. Results: The result of climate change projections showed that the average annual minimum temperature will be increased by about 0.8-2.9°C. The mean annual maximum temperature will be also increased by 0.9-3.75 °C. The rainfall projection generally showed an increasing trend, it exhibited an average annual increase of 3.5-13.4 % over the study area. The drought projection showed that there would be extreme drought events in study area for the future (2018-2099). The SPI result indicates that drought will be occurred in the study area after 1-5 and 1-6 years under RCP 4.5 and 8.5 emission scenarios respectively and the RDI value also shows drought will occurred after 1-6 and 2-7 years under RCP 4.5 and RCP 8.5 emission scenarios respectively over the study area. Almost more than 72% of the current and future spatial coverage of drought in the study area will be affected by extreme drought, 22.3% severely and 5.57% also moderate drought.Conclusions: Therefore, the study helps to provide useful information for policy decision makers to implement different adaptation and mitigation measures of drought in the region.