ENSO

Seuils retenus :
El Niño : weak 0.5/0.9, moderate 1.0/1.4, strong 1.5/1.9, very strong ≥ 2.0.
La Niña : weak -0.5/-0.9, moderate -1.0/-1.4, strong -1.5/-1.9, very strong ≤ -2.0.