According to scientists, the El Niño phenomenon should reach neutrality by fall 2024. But another phenomenon whose impact on weather conditions is the opposite of El Niño could well take its place in the months to come, it’s La Niña.
“ We passed the peak intensity of El Niño at the end of 2023 and we are now in a phase of rapid attenuation, as is typically the case in this type of situation… All models see the return to normal conditions by spring », Explains Pierre Bonnin, climatologist at Météo France, interviewed by Ouest-France. Still according to the specialist, “ some models then switch to La Niña conditions “. A trend confirmed by Noaa, the American oceanographic agency, which estimates that the chances of a return of La Nina next fall are 80%.
A phenomenon that causes cooling
Furthermore, it is necessary to remember what this completely different phenomenon from El Nino is. Simply put, La Niña is manifested by a significant drop in the surface temperature of the waters of the eastern Pacific Ocean. This is due to strengthening winds and currents in the western Pacific Ocean that move warm surface waters towards the Asian continent. Consequently, rising water causes the surface to cool. “ La Niña is an accentuated normal situation », summarizes Pierre Bonnin.
La Niña impacts different parts of the globe differently. It is notably responsible for the increase in the number of cyclones in the western Pacific, the drought affecting East Africa, as well as eastern South America and the considerable increase in the rate of humidity in southern Africa. “ It favors drier conditions in the Middle East and southern United States », specifies Pierre Bonnin. In Europe, La Niña is associated with potentially colder winters in the east of the continent, with variations in precipitation patterns and modulation of atmospheric currents.
What consequences for France?
A return of this phenomenon would therefore impact atmospheric temperature globally. Nevertheless, ” La Niña is traditionally a less pronounced phenomenon than El Niño, so the cooling that may occur will be a little weaker », Indicates Pierre Bonnin. In addition, the meteorologist explains that global warming further attenuates the effects of the La Niña phenomenon on atmospheric temperature. Consequently, the impact of the phenomenon La Nina on weather conditions should have no major consequences, particularly in France.