La Niña giving way to El Niño

The climate monitoring services have confirmed the end of La Niña, which has been ongoing since 2020. La Niña is a climate phenomenon which recurs every three to four years. However the one which has just finished deserves to be treated as exceptional, because of its length. It stretched over three consecutive seasons: 2020-2021, 2021-2022 and 2022-2023. We need to go back to 1999-2001 to find a phenomenon of similar duration.  

While a return to normal atmospheric conditions is predicted this spring, the models are already indicating a high probability (62 %) of El Niño occurring by the end of 2023. This phenomenon, which is the opposite of La Niña, contributes to heating the waters of the South Pacific, reaches maximum intensity around Christmas: dry conditions develop over Indonesia and Australia, tropical storms and hurricanes appear much further East than usual, while the Peruvian and Ecuadorian coasts see unusual rainfall levels, causing floods and landslides. The forerunners of a high-intensity phenomenon are can already be seen in South America, with in particular cyclone Yaku appearing on the Pacific Coast in early March 2023, behind historic record rainfall which caused floods in the Peru’s northern zones (Tumbes, Piura, Lambayeque). Similarly, abnormally high rainfall has been reported in the Guayas and Los Rios regions in Ecuador since March. There are reports of rivers bursting their banks, causing localised flooding.

We need to go back to the 2014-2016 season to find a high-intensity El Niño phenomenon. The 2015-2016 episode, the most intense since 1997-1998, was marked by heavy drought in Colombia and throughout the Caribbean, in particular causing banana production falls.