Changes in the frequency and severity of hydrological droughts over Ethiopia from 1960 to 2013


  • A. M. El Kenawy Lecturer in Physical Geography, Department of Geography, Faculty of Education, Mansoura University, Mansoura, Egypt
  • M. F. McCabe Division of Biological and Environmental Sciences and Engineering King Abdullah University of Science and Technology Thuwal
  • S. M. Vicente-Serrano Instituto Pirenaico de Ecología (CSIC)
  • J. I. López-Moreno Instituto Pirenaico de Ecología (CSIC)
  • S. M. Robaa Cairo University



Drought, Standardized Precipitation Index, Precipitation, Variability, Trends, Principal Component Analysis, Ethiopia


Here we present an analysis of drought occurrence and variability in Ethiopia, based on the monthly precipitation data from the Climate Research Unit (CRU-v3.22) over the period from 1960 to 2013. The drought events were characterized by means of the Standardized Precipitation Index (SPI) applied to precipitation data at a temporal scale of 12 months. At the national scale, the results reveal a statistically significant decrease in the severity of droughts over the 54-year period, a pattern that is mostly attributed to a statistically significant decrease in the frequency of high intensity drought episodes (i.e., extreme and very extreme droughts), compared to moderate droughts. To assess the general patterns of drought evolution, a principal component analysis (PCA) was applied to the SPI series. PCA results indicate a high spatial heterogeneity in the SPI variations over the investigated period, with ten different spatially well-defined regions identified. These PCA components accounted for 72.9% of the total variance of drought in the region. These regions also showed considerable differences in the temporal variability of drought, as most of the regions exhibited an increase in wetness conditions in recent decades. In contrast, the regions that receive less than 400 mm of annual precipitation showed a declining  trend, with the largest changes occurring over Afar region. Generally, the highly elevated regions over the central Ethiopian Highlands showed the weakest changes, compared to the lowlands. This study confirms the local character of drought evolution over Ethiopia, providing evidence for policy makers to adopt appropriate local policies to cope with the risks of drought. Over Ethiopia, the detailed spatial assessment of drought evolution is required for a better understanding of the possible impacts of recurrent drought on agriculture, food production, soil degradation, human settlements and migrations, as well as energy production and water resources management across Ethiopia.


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How to Cite

El Kenawy AM, McCabe MF, Vicente-Serrano SM, López-Moreno JI, Robaa SM. Changes in the frequency and severity of hydrological droughts over Ethiopia from 1960 to 2013. CIG [Internet]. 2016 Jun. 27 [cited 2024 Apr. 19];42(1):145-66. Available from: