According to the latest bulletin from the World Meteorological Organization (WMO), there is a 55% chance of developing a La Niña episode “during the period from December 2024 to February 2025”, but “it should be short and of low intensity”.

In the previous bulletin, released in September, the probability of a La Niña episode occurring in the same period was estimated at 60%.

“The year 2024 began with El Niño and could become the hottest year on record”, points out the secretary general of the WMO, Celeste Saulo, in a statement.

“Even if the La Niña phenomenon, known for temporarily cooling the climate, occurs, it will not be enough to offset the warming induced by record levels of greenhouse gases, the specificity of which is to retain heat in the atmosphere,” she added.

For the period February to April next year, there is a 55% chance of a return to neutral conditions.

In general, La Niña causes large-scale climate variations opposite to those associated with El Niño, causing the cooling of the surface waters of the tropical, central and eastern Pacific Ocean, associated with variations in tropical atmospheric circulation, for example in winds, pressure and precipitation, explains the WMO.

The United Nations agency recalls that climatic phenomena of natural origin, such as La Niña and El Niño, are affected by climate change linked to human activities, “which cause an increase in global temperatures, accentuate extreme meteorological and climatic conditions and modify seasonal patterns of precipitation and temperature”.

Thus, highlights Celeste Saulo, “despite the absence of El Niño or La Niña conditions since May, we have witnessed a series of extreme weather phenomena, including record rainfall and floods, which unfortunately have become the new normal in the context of climate change”.