Heat is no longer a future climate risk. It is already here.

Across continents, high temperatures are being pushed higher by forces acting at once: human-caused warming, very warm oceans, dry soils, slow-moving high-pressure weather systems and El Niño conditions that have now developed in the tropical Pacific.

El Niño is a natural warming of part of the tropical Pacific that can shift weather patterns around the world. It is not the cause of climate change, but when it develops in a climate already warmed by greenhouse gas pollution, it can add another push to global temperatures and regional extremes.

The science is clear. Greenhouse gases have raised the baseline, so heatwaves now begin from a warmer starting point. Record ocean heat adds more energy to the climate system. Dry ground can intensify heat, because less of the sun’s energy goes into evaporating water from soil and plants, and more goes into heating the air.

Weather patterns decide where that heat lands. A “heat dome” happens when a high-pressure system settles over a region. Air sinks, clouds are suppressed and temperatures can climb for days. The danger grows when nights remain hot, because bodies, buildings and infrastructure get little chance to cool.

El Niño’s effects vary by region and season, so it will not explain every heatwave in 2026. But it is now being added to long-term warming, and that combination can raise the risk of more extreme heat, drought or heavy rainfall in some regions, including parts of Asia, Australia and the Americas.

In the UK, Kew Gardens reached 35.1°C in late May, provisionally breaking the national May temperature record for the second day in a row. The previous record,........

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