El Nino could make 2027 hottest year, Met Office says

This year's El Nino weather pattern is expected to be the biggest in more than a century and could make 2027 the hottest year globally, Britain's Met Office predicted Friday.

Adam Scaife, head of long-range forecasting at the weather agency, told the BBC: “We are expecting the biggest El Nino for over a century, peaking at something over three degrees -- that is unheard of in modern climate records.”

That would mean Pacific water heating more than 3C above the norm in the coming months. El Nino is declared when sea surface temperatures in the tropical eastern Pacific rise at least 0.5C above the baseline.

The Climate Brink dashboard, using data from the US National Oceanic and Atmospheric Administration, put Pacific region temperatures at about 2.6C above a rolling 30-year average. The dashboard also aggregates forecasts that put El Nino on course to peak at a 3.9C anomaly in November, above a 3C anomaly detected in 2015.

Scaife called the forecast “an unprecedented event” in a Met Office blog and said he had never seen an El Nino signal so intense in the agency's forecasts.

El Nino can change winds, atmospheric pressure and rainfall patterns worldwide, and can raise global temperatures overall. The Met Office said a record El Nino would add to the stresses of climate change after a summer of heatwaves across Europe.

Scaife said this year's anomalous warmth would have particularly strong effects across the Tropics, with forecasters expecting severe droughts in places such as South America and the West Pacific. The Met Office said El Nino was already causing well below normal rainfall in India and was expected to bring increased rainfall and storminess in the UK around November.

Nick Dunstone, another Met Office scientist, said 2027 is now “very likely to replace 2024 as the warmest year on record”. In 2024, global temperatures exceeded 1.5C above the preindustrial period, the limit set by international commitments to curb global warming. Last year was the third hottest on record.

El Nino is part of a natural cycle that occurs every two to seven years, according to meteorologists. Scientists agree climate change increases its impacts.