El Niño Technical Note

The El Niño–Southern Oscillation (ENSO) is one of the major drivers of interannual climate variability worldwide. Its different phases influence tropical atmospheric circulation and modulate rainfall regimes in many regions of the world, including West Africa and the Sahel. Historically, El Niño events have often been associated with reduced precipitations in the Sahel, longer dry spells, and higher temperatures. However, recent scientific evidence shows that the relationship between ENSO and rainfall in West Africa is neither constant nor systematic. The impact of El Niño depends strongly on the state of other ocean basins, particularly the tropical Atlantic, the Mediterranean Sea, and the Indian Ocean. For 2026, a major EL NINO event is under development, what would be its impact on the rainy season in our sub-region?