Global‐scale sea‐surface temperature anomalies and rainfall characteristics in northern Nigeria

Abstract

Composite rainfall data over the 35‐year period 1951–1985 from seven Nigerian synoptic stations, all around latitude 12°N, have been used to examine the correlation, or otherwise, between global‐scale sea‐surface temperature (SST) anomalies and rainfall characteristics on the fringe of the Sahel. Results show that SST anomalies of the Indian, North Atlantic and South Atlantic Oceans are correlated with total rainfall and number of rain days while the anomalies of the tropical East Pacific may have influence on rainfall intensity at the beginning of the rainy season. It is indicated that Pacific El Niño events may affect the frequency of occurrence of the main rain‐producing mechanism in the Sahel; namely, squall lines. Extraordinary warmings in the South Atlantic are also shown to cause considerable shortfalls in expected mean monthly distribution of rainfall, especially in August, the main rainy month in the Sahel.