Scientists say this summer could be the world's hottest on record, even as the warming effect of El Nino fades out to be replaced with the cooling La Nina.
An exceptional 12-month streak has seen every month through to May reach a new temperature high.
The records look set to continue, with scientists predicting the June to September period will remain hotter than average.
Heatwave warnings were issued in multiple countries this month, with soaring temperatures in parts of the US, Greece, Athens, Italy and the UAE, where the temperature reached more 50.3°C in the Um Azimul area of Al Ain this week.
Selwin Hart, UN special adviser on climate change, has warned that the recent spate of heatwaves is a sign of things to come.
“With every fraction of a degree of warming, dangerous heat is hitting larger regions of the world for many more days of the year,” said Friederike Otto, senior lecturer in Climate Science at the Grantham Institute – Climate Change and the Environment, at Imperial College London. “Last year, the world created about 37.4 billion tonnes of fossil fuel emissions, which is more than any other year.
“These planet-heating emissions mean this summer could become the hottest ever recorded, even with El Nino fading and shifting to La Niña.”
El Nino is a naturally occurring weather phenomenon which occurs every few years involving the warming of sea surface temperatures. That releases additional heat into the atmosphere, which produces wetter and warmer air.
It is normally, but not always, followed by La Nina, which has an opposite, cooling, effect.
The latest El Nino, which began in June 2023, peaked among the five strongest such events on record, according to the World Meteorological Organisation.
In May, the EU's Copernicus climate change service said El Nino continued to weaken “towards neutral conditions”.
But marine air temperatures in general remained “at an unusually high level” and have been high in many areas since.
“As of now it seems that it is surpassing what we recorded last June,” Akshay Deoras, a research scientist at the National Centre for Atmospheric Science and the Department of Meteorology at the University of Reading, told The National.
“So it seems to be a tight competition between the two years, 2023 and 2024. But I won’t be surprised if June 2024 overtakes what we saw in 2023.”
July and August will likely also continue the record-breaking streak, he said.
La Nina is now forming. But its cooling effect is not a light switch that takes place over a period of days. It takes months for it to take hold.
And in the context of a warming planet due to human-caused climate change, scientists say that the cooling effect may be minuscule.
Scientists are predicting this year will still be a top-five global mean temperature record, even accounting for the impact of La Nina.
“The second half of this year is when we would see things start to cool down,” said Mr Deoras.
“The first indication of that would be when global average temperatures for different months will be below what we recorded last year, for 2023.
“But they still won’t be anywhere close to the last average of 30 years and so on.
“We are still way above long-term average temperatures.”
