Linkages between El Niño-Southern Oscillation (ENSO) and precipitation in West Africa regions

The impact of climate change through oceanic and atmospheric transport had greatly influenced human living. The spatial and temporal variation of rainfall across the earth has been linked to climate change and atmospheric-oceanic mechanism. Flood or drought occurrence is a function of precipitation anomalies, and some regions in West Africa have recorded the occurrence of drought or flood in recent time. The connection between precipitation and El Niño-Southern Oscillation events across West Africa was examined in this paper. Monthly rainfall data ranges between 1979 and 2018 were collected from NCEP Climate Prediction Center (CPC). Parametric and nonparametric approaches were used to investigate the correlation between Southern Oscillation Index (SOI) and precipitation anomalies during the El Niño, La Niña, and non-ENSO periods. The results show that the values of the correlation between SOI and precipitation anomalies increase northward during the wet season for both La Nina and El Nino periods. Strong links were established between SOI and precipitation anomalies, ranging between − 0.45 and 0.35 and decreasing northward during the dry season at El Nino period. The result of the correlation between SOI and precipitation anomalies during La Nina dry season period is altitudinal dependent. Using the dynamic slope of the segmented regression, El Niño showed a strong positive influence on the precipitation in the Guinea region. The result will help the policy makers to mitigate against the effect of ENSO in West African countries.