Effects of changes in ENSO on seasonal mean temperature and rainfall in Nigeria

Abstract

This study investigates the effects of El Niño/Southern Oscillation (ENSO) on temperature and rainfall in Nigeria. The persistent rise in population with more demands for rainfall and water supply in Nigeria requires a better understanding of the impacts of ENSO (La Niña, El Niño) induced changes on the precipitation patterns under future climate conditions. Thus, we compared the sea surface temperature (SST) from the ENSO regions of the Tropical Pacific Ocean (Niño 3 (150°W-90°W, 5°S-5°N) and Niño 4 (160°E-150°W, 5°S-5°N)) with the observed temperature from Nigeria and the temperature is further compared with the associated rainfall. The results show that an increase or decrease in the Niño 3 and Niño 4 SST is accompanied by a corresponding change in the temperature over Nigeria; however, there is better agreement with the Niño 3 SST compared to the Niño 4 SST. The investigation suggests that a slight northward (southward) shift in the mean position of Intertropical Convergence Zone (ITCZ) during a La Niña (El Niño) event is followed by a reduction (increase) in the average temperature within Nigeria while the mean precipitation rises (reduces) over the country. These results could aid weather prediction which might improve the economy as well as save lives and property during climate-related hazards like drought, forest fires and floods.