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Recent drought tendencies in Ethiopia and equatorial-subtropical eastern Africa

Chris Funk·Gabriel B. Senay·Alemu Asfaw·James Verdin·Jim Rowland·Diriba Korecha·Gary Eilerts·Joel Michaelsen·Saud A. Amer·Richard Choularton
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Abstract

This report presents an analysis of Ethiopian rainfall from 1960 through 2004, based on 186 gauges in Ethiopia and 373 gauges from surrounding countriesi. Substantial post1997 declines in March-September rainfall have been observed in the northeast, southeast and southwestern portions of the country, a result corroborated by several independent data sourcesii. The observed rainfall reductions have been accompanied by an increase in millions needing food aid (Figure 1). The greatest percent decrease has occurred during the Belg (March-May) season, though Kiremt (June-September) rains have also diminished in many areas. This recent dryness may be linked to a warming tendency in the southern Indian Oceaniii, and is likely to impact densely populated and/or water-insecure regions of southern and eastern Ethiopia. These areas face declines in rainfall and increasing demands on land, water and agriculture. Recent dryness, dropping coffee prices, rising population and land degradation combine to create mounting destitution that must be countered with innovative planning and policiesiv. This report is organized as follows. Section 1 provides context for our results by summarizing recent trends in food aid, precipitation and the regional climate. Section 2 quantifies the water availability situation by analyzing potentially available runoff. Section 3 describes the results of our historical rainfall analysis. Section 4 relates the observed rainfall variations to circulation and sea surface temperature patterns in the Indian and Pacific Oceans. Section 5 briefly summarizes our results.

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90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: -23.352854066043264° to 22.343695928883136° latitude; 22.02134670189892° to 52.702144088498756° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Chris Funk, Gabriel B. Senay, Alemu Asfaw, James Verdin, Jim Rowland, Diriba Korecha, Gary Eilerts, Joel Michaelsen, Saud A. Amer, Richard Choularton. 2005. Recent drought tendencies in Ethiopia and equatorial-subtropical eastern Africa. https://pubs.usgs.gov/publication/70259484

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