Research Article
Trends and spatial distribution of annual and seasonal rainfall in Ethiopia
Article first published online: 5 MAR 2008
DOI: 10.1002/joc.1623
Copyright © 2008 Royal Meteorological Society
Additional Information
How to Cite
Cheung, W. H., Senay, G. B. and Singh, A. (2008), Trends and spatial distribution of annual and seasonal rainfall in Ethiopia. Int. J. Climatol., 28: 1723–1734. doi: 10.1002/joc.1623
Publication History
- Issue published online: 16 OCT 2008
- Article first published online: 5 MAR 2008
- Manuscript Revised: 11 AUG 2007
- Manuscript Accepted: 11 AUG 2007
- Manuscript Received: 28 DEC 2006
- Abstract
- References
- Cited By
Keywords:
- Ethiopia;
- climate;
- trend analysis;
- hydrology;
- precipitation;
- rainfall distribution
Abstract
As a country whose economy is heavily dependent on low-productivity rainfed agriculture, rainfall trends are often cited as one of the more important factors in explaining various socio-economic problems such as food insecurity. Therefore, in order to help policymakers and developers make more informed decisions, this study investigated the temporal dynamics of rainfall and its spatial distribution within Ethiopia. Changes in rainfall were examined using data from 134 stations in 13 watersheds between 1960 and 2002. The variability and trends in seasonal and annual rainfall were analysed at the watershed scale with data (1) from all available years, and (2) excluding years that lacked observations from at least 25% of the gauges. Similar analyses were also performed at the gauge, regional, and national levels. By regressing annual watershed rainfall on time, results from the one-sample t-test show no significant changes in rainfall for any of the watersheds examined. However, in our regressions of seasonal rainfall averages against time, we found a significant decline in June to September rainfall (i.e. Kiremt) for the Baro-Akobo, Omo-Ghibe, Rift Valley, and Southern Blue Nile watersheds located in the southwestern and central parts of Ethiopia. While the gauge level analysis showed that certain gauge stations experienced recent changes in rainfall, these trends are not necessarily reflected at the watershed or regional levels. Copyright © 2008 Royal Meteorological Society

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