A year of record temperatures and extreme weather - from floods to fires - is due to a deadly cocktail of man-made climate change mixed with cyclical El Niño weather, scientists say.
A spate of recent heatwaves in West Africa, for example, would not have happened without climate change and was made still worse by the El Niño event, scientists from the World Weather Attribution (WWA) group found in a new report.
The scientists say extreme events such as these will become much more common - and more dangerous - without a rapid cut in planet-heating greenhouse gas emissions.
So what is El Niño and how does it interact with climate change?
What is El Niño?
It’s what happens when unusually warm surface temperatures in the eastern Pacific Ocean unleash a domino effect on weather patterns right around the globe.
El Niño, which on average happens every 2 to 7 years as part of a natural cycle, lasts 9 to 12 months, a period that began last June and has now ended, according to Australia’s Bureau of Meteorology.
This warm spell is followed by a neutral period which could then shift to unusually cold ocean surface temperatures, called La Niña, later this year.
El Niño is a phenomenon distinct from our human-driven climate crisis, said Richard Allan, a climate scientist at the University of Reading, but its impacts will be all the more intense in a warmer atmosphere.
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Studies have shown that many extreme weather events have been driven by a combination of both climate change and El Niño.
Joyce Kimutai, researcher, Grantham Institute at Imperial College London
