UN: Above-average temperatures despite La Nina

Temperatures in many parts of the world are expected to be above average in coming months despite the cooling effect of a La Nina weather phenomenon, the United Nations said on Tuesday (November 30).

The UN's World Meteorological Organization (WMO) said La Nina, which last held the globe in its clutches between August 2020 and May this year, had reappeared and is expected to last into early 2022.

This, it said, would influence temperatures and precipitation, but despite the phenomenon's usual cooling effect, temperatures were likely to remain above average in many places.

"The cooling impact of the 2020/2021 La Nina, which is typically felt in the second half of the event, means that 2021 will be one of the 10 warmest years on record, rather than THE warmest year," WMO Chief Petteri Taalas said in a statement.

"This is a short-lived respite and does not reverse the long-term warming trend or reduce the urgency of climate action."

La Nina refers to the large-scale cooling of surface temperatures in the central and eastern equatorial Pacific Ocean, occurring every two-to-seven years.

The effect has widespread impacts on weather around the world -- typically the opposite impacts to the El Nino phenomenon, which has a warming influence on global temperatures.

But the WMO has warned that global warming is helping to worsen and distort the effects of such natural phenomena.

The UN agency said there was a 90% chance of tropical Pacific Sea surface temperatures remaining at La Nina levels until the end of 2021 and a moderate chance, between 70-80%, for them to persist at La Nina levels through the first quarter of 2022.

Many land areas were expected to see above-average temperatures, with an unusually warm winter expected in the northern and north-eastern parts of Asia and the Arctic.

Temperatures were predicted to be above average in the eastern and south-eastern parts of North America, most of Europe and north-eastern parts of Asia.

Higher-than-normal temperatures were also expected near equatorial Africa, including over already drought-hit Madagascar, considered to be facing the world's first climate-change sparked famine.

WMO said unusually wet conditions were meanwhile predicted in parts of Southeast Asia and northern parts of South America, while unusually dry conditions could be expected below the equator in South America and in parts of southern Asia and the Middle East.