Nearly half a million people are projected to die in the next six months from soaring temperatures brought by the super El Niño, which has already reached record-breaking levels.

The climate phenomenon, which forms in the Pacific Ocean, is “firmly established and is expected to strengthen further” in the coming months before peaking at the end of the year, according to the World Meteorological Organisation (WMO).

Climate scientists now predict 451,000 people across the world will die due to additional heat.

Professor Michael Greenstone, co-founder of the Climate Impact Lab which produced the report on additional deaths, said this is “such a large number that it can be numbing, but it is made up of parents and children, grandparents and neighbours, people going to work, caring for families, and living their lives”.

The temperature rise in the Pacific Ocean where the El Niño forms has now reached 3.08°C, latest data shows. This is above the 3.02°C registered in November 2015 – the previous high in 150 years of records. The temperature is measured against the average of 1991-2020.

El Niño is part of a natural cycle, called the El Niño–Southern Oscillation, and forms when warmer waters spread across the central and eastern Pacific Ocean. It is associated with widespread changes in the climate system that can last for up to a year.

The WMO said there was an “exceptionally high likelihood of nearly 100 per cent” that this El Niño will last until February 2027.

A milder, wetter and stormier UK

Despite occurring far from the UK, its effects are felt worldwide, including disrupting vital global supply chains and potential for flooding and drought in some countries – exacerbating the effect of climate change.

El Niño could bring wetter and milder weather to the UK through the autumn and winter, said Professor Ilan Kelman of UCL’s department of risk and disaster reduction.

“There’s nothing definite, but in general we would expect a milder, wetter, and stormier autumn, a colder winter, and then a possibility of a hotter summer next year.”

The El Niño of 1998 is the strongest of this century so far and saw more storms in the UK and the warmest year on record at the time.

Experts at the Met Office said the phenomenon, which has already been labelled a “super” or even “Godzilla” El Nino, had exceeded previous records with several weeks to go before it is to peak.

Large parts of England went months without any significant rainfall after one of the driest and warmest summers on record this year (Photo: Leon Neal/Getty)

Dr Alison Ming, research fellow in the Atmosphere-Ocean Dynamics Group at Cambridge University, said: “What we do know is global thermal temperatures are rising, so you have an increase to your baseline.

“The super El Niño is likely to also give you another sixth of a degree increase on top of that to your global depth temperatures.”

However, she warned that the direct impact of El Niño on Europe is “a lot more uncertain” due to its distance.

The Met Office warns that El Niño is “just one (albeit very important) influence on climate variability”.

It adds that the weather response to El Niño “should not be seen as inevitable” and “should be regarded as shifting the odds in favour of the typical response which may, for example, increase the risk of heavy rainfall and consequent damage in a particular region or season”.

Plane turbulence and supply chains disrupted

The more severe impact of El Niño on other countries could also have a knock-on effect on the economy and daily life in the UK.

Kelman said: “Perhaps more of concern is that El Niño definitely affects the weather in other places around the world, and so that can impact UK supply chains.

“We may see certain weather happening elsewhere, which then can lead to perhaps turbulence when we’re flying, perhaps increased flooding in certain places, which impacts electronic supply chains, and we may see consequences for imported food.”

Rice, sugar or coffee imports could be affected by potential flooding in South America. The shift of rainfall brought on by El Niño can also cause severe droughts in South East Asia and Australia.

“There is always a potential, for example, whether it’s wine or more exotic fruits and vegetables, to be less common on the UK shelves,” added Kelman.

Major floods near Bangkok in 2011 showed the potential impact on global electronic and manufacturing supply chains with a World Bank estimate of $46.5bn (£34.5bn) in total economic damages.

During El Niño, sea temperatures in the tropical eastern Pacific rise to at least 0.5°C above the long-term average. This year, they are forecast to increase by more than 3°C, the Met Office said.

The Climate Impact Lab report projected the most El Niño-related heat deaths in Nigeria (31,320), Indonesia (19,251) and Sudan (17,430).