The El Niño weather pattern is likely to develop later this year and could contribute to rising global temperatures, a United Nations agency said on Wednesday.
The UN's World Meteorological Organization (WMO) said that after three years of the La Niña weather pattern in the Pacific Ocean, which often lowers global temperatures slightly, there was a 60 per cent chance that will change to El Niño, its warmer counterpart, in May-July this year.
That probability will increase to 70-80 per cent between July and September, according to the WMO.
Speaking to reporters in Geneva, Wilfran Moufouma Okia, head of the WMO regional climate prediction services division, said there was no current estimate of how much El Niño would push temperatures up.
"El Niño will fuel the temperature globally," he said. "We feel the effect of El Niño temperatures globally with a slight delay."
The WMO said it could not predict the strength or duration of El Niño.
The world's hottest year on record so far was 2016, coinciding with a strong El Niño – although climate change has fuelled extreme temperatures even in years without the phenomenon.
During El Niño, winds blowing west along the equator slow down, and warm water is pushed east, creating warmer surface ocean temperatures.
