GENEVA, March 6, 2025 (BSS/AFP) - The cooling weather phenomenon La Nina that emerged late last year is weak and likely to be brief, the UN said Thursday, dashing hopes it could help rein in soaring global temperatures.

"The weak La Nina event that emerged in December 2024 is likely to be short-lived," the United Nations' World Meteorological Organization said in its latest update.

There is currently a 60-percent probability that conditions will shift back to neutral between this month and May, it said, adding that chances increased to 70 percent between April and June.

The WMO had last year voiced hope the return of La Nina would help lower temperatures slightly after months of global heat records fuelled in part by La Nina's opposite number, the warming El Nino weather pattern, which gripped the planet for a year from June 2023.

But the phenomenon appeared unlikely to significantly impact temperatures after 2024 ticked in as the hottest year ever recorded.

Despite the presence of weak La Nina conditions, WMO pointed out Thursday that "January 2025 was the warmest January on record".

And it said its latest global seasonal climate update, which looks beyond just the impact of the El Nino and La Nina phenomena, noted that "above-normal sea surface temperatures (were) expected to persist across all major oceans -- except for the near-equatorial eastern Pacific".

It also forecast "above-average temperatures over nearly all land areas worldwide".

La Nina refers to a naturally occurring climate phenomenon that cools the ocean surface temperatures in large swathes of the tropical Pacific Ocean, coupled with winds, rains and changes in atmospheric pressure.

In many locations, especially in the tropics, La Nina produces the opposite climate impacts to El Nino, which heats up the surface of the oceans, leading to drought in some parts of the world and triggering heavy downpours elsewhere.

The agency said the probability El Nino developing again between now and June was "negligible".

While both are natural climate events, WMO stressed they were "taking place in the broader context of human-induced climate change, which is increasing global temperatures, exacerbating extreme weather and climate, and impacting seasonal rainfall and temperature patterns".

WMO chief Celeste Saulo stressed in the update that seasonal forecasts for El Nino and La Nina and the associated impacts on weather and climate patterns globally were "an important tool to inform early warnings and early action", and help support decision-making.

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