Characterizing the Spatiotemporal Distributions of Meteorological Droughts as a Response to Climate Variability: The case of rift valley lakes basin of Ethiopia

Climate variability and recurrent meteorological droughts frequently affect the rain-dependent Ethiopian agriculture, where the rift valley lakes basin is one of the most drought-prone regions in the country. The aim of this study was to evaluate climate variability and characterize the spatiotemporal distribution of meteorological droughts using a merged satellite-gauge rainfall across the major agroecological zones (AEZs) of the rift valley lakes basin. To this end, coefficient of variation (CV) and standardized rainfall anomaly (SRA) were used to evaluate rainfall variability; Mann-Kendell test was used to examine trends of temperature and rainfall; and a grid-rainfall based standardized precipitation index (SPI) was used to assess the spatiotemporal distribution and severity of meteorological droughts. The SPI was computed for 37 years over 1981–2017 at 3-month and 4-month timescales for the bimodal rainy seasons. Finally, a higher inter-annual and spatial variability of rainfall a...