Climate change: La Niña fades, as global heat keeps rising

La Niña, a natural climate phenomenon, results in cooler Pacific Ocean temperatures and influences weather conditions worldwide. The latest forecasts from WMO indicate sea surface temperatures in the equatorial Pacific are expected to return to normal.

The agency says that there is a 60 per cent chance conditions will shift back to what scientists call an ENSO-neutral temperature range during March-May 2025, increasing to 70 per cent for April-June 2025.

ENSO (El Niño-Southern Oscillation)-neutral simply means the ocean is neither unusually warm (El Niño) nor unusually cool (La Niña). Likewise, the probability of El Niño developing is very low during this period, the agency said.

According to WMO Secretary-General Celeste Saulo, El Niño and La Niña associated forecasts are critical for early warnings and taking preemptive action.

“These forecasts translate into millions of dollars’ worth in economic savings for key sectors like agriculture, energy and transport, and have saved thousands of lives over the years by enabling disaster risk preparedness”.

La Niña, with its large-scale cooling of ocean surface temperatures in the central and eastern Pacific, changes wind, pressure, and rainfall. Typically, it brings climate impacts opposite to El Niño, especially in tropical regions.

For instance, during El Niño, Australia often experiences drought, whereas La Niña can bring increased rainfall and flooding. In contrast, parts of South America may experience drought during La Niña but wetter conditions during El Niño.

Bringing the heat

Notably, these natural climate events are currently occurring alongside human-caused climate change, which is warming the planet and causing more extreme weather. According to WMO, January 2025 was the warmest January on record, despite the cooler La Niña conditions.

The agency looks at ENSO but also issues regular Global Seasonal Climate Updates (GSCU) that provide a more comprehensive climate outlook based on other key patterns such as those in the Atlantic and Arctic. These updates also track sea temperatures, global and regional temperature and rainfall changes.

With most maritime regions set to be warmer than normal, except in the eastern Pacific, WMO forecasts above-average temperatures across nearly all land areas worldwide during the upcoming season.