WMO puts likelihood of La Nina at 60pc from October

There is a 60pc chance of La Nina weather conditions emerging from October to February next year, the World Meteorological Organisation (WMO) said today.

The chance of the El Nino pattern redeveloping during that time are "negligible", it said.

La Nina generally leads to a cooling effect on a global level, while El Nino typically has the opposite effect. The weather patterns are naturally occurring, but "are taking place in the broader context of human-induced climate change" that is increasing temperatures globally, the WMO said.

The past nine years have been the warmest on record, even with the cooling influence of a La Nina period from 2020 to early 2023, the organisation noted.

"Even if a short-term cooling La Nina event does emerge, it will not change the long-term trajectory of rising global temperatures due to heat-trapping greenhouse gases in the atmosphere", WMO secretary-general Celeste Saulo said.

Last month was the joint-hottest August on record, and was on average 1.51°C above pre-industrial levels. The Paris climate agreement seeks to limit global warming to "well below" 2°C above pre-industrial temperatures, and preferably to 1.5°C.

Global temperatures have been at or close to record highs to date this year and it is "increasingly likely that 2024 is going to be the warmest year on record", EU earth-monitoring service Copernicus said last week.

By Georgia Gratton