The Uncertain Influence of the African Great Lakes and the Indian Ocean Dipole on Local-scale East Africa Short Rains

Abstract

Precipitation in East Africa has the potential to enrich the lives of or bring ruin to millions of people that rely heavily on agriculture. Precipitation itself is in turn reliant on regional and extra-regional factors. The Indian Ocean Dipole (IOD) is such a factor and in this paper, its influence on the short rains that occur from October to December is studied through a quantitative assessment of information flow (IF) between the Dipole Mode Index and stations scattered throughout Burundi, Rwanda, and Uganda. Although it was initially thought that the African Great Lakes would have had an effect on the sensitivity of a given station's precipitation to the IOD, clear patterns on which stations were most sensitive or insensitive to IOD activity could not be properly identified. This is perhaps due to a plethora of atmospheric and topographic factors that contribute to local precipitation. As such, additional research is strongly encouraged to elucidate the reason, if any, and excluding statistical artifacts, for observed discrepancies.