Journal of Kenya Meteorological Society
Linkages between the Indian Ocean Dipole and East African Seasonal Rainfall Anomalies
Zablone Owiti*, Laban A. Ogallo**, Joseph Mutemi***
*National Council for Science and Technology, **IGAD Climate Prediction and Applications Centre, ***University of Nairobi, Department of Meteorology
National Council for Science and Technology
P O Box 30623, 00100, Nairobi, Kenya
(Manuscript received 12 March 2007, in final form 29 November 2007)
This study was designed to understand the nature of the relationship between the Indian Ocean Dipole (IOD) index and seasonal rainfall in East Africa using statistical approaches. The statistical methods used in this study include correlation, regression and composite analyses. Results from the analyses suggested that the pattern in Sea Surface Temperature (SST) anomalies manifested during the IOD events have strong signals on the regional climate system during the October to December rainfall season. The study has demonstrated that some of the extreme rainfall conditions over East Africa were associated with positive and negative IOD phases. The linkages were strong during El Niño/La Niña years. Such information will help to improve monitoring, prediction and early warning of extreme rainfall events over east Africa to reduce the vulnerability of the society of the region to negative impacts of extreme rainfall events that are common in the region.