Influence of El Niño on rainfall in Guyana and Uganda

Abstract

El Niño/southern oscillation (ENSO) activity is known to affect weather patterns in many parts of the world. This paper develops an approach to identifying signals and incorporating associated impacts on hydrological risk into water resources planning and management. The paper builds on earlier research reported in the climatology literature, and brings this to the engineering domain. An evaluation of seasonal rainfall in Guyana clearly demonstrates that distinct rainfall distributions are associated with La Niña and El Niño events. Forecasts of these events are made by a number of organisations at lead times of up to eight months. If these are coupled with the precipitation analysis presented in this paper, an objective hydrological risk assessment can be made. The methodology applied in Guyana has been repeated with data on net basin supply to Lake Victoria. There is a clear indication of a link between ENSO activity and net basin supply to Lake Victoria.