The July heatwave in Europe would have been as much as 3C (5.5F) cooler if the world’s climate was not changing, according to research.
There is “extremely little chance” some of the high temperatures would have been recorded were it not for the impact of humans, says the World Weather Attribution report.
It adds that record temperatures seen in France and the Netherlands last month, where it hit over 40C (104F), would only happen about once every 1,000 years without climate change.
And heatwaves like those in the UK and Germany would only occur “from a few tens to a few hundreds of years without climate change”.
“In all locations an event like the observed would have been 1.5 to 3C cooler in an unchanged climate,” says the report.
It says European heatwaves since 2003 have been made “much more likely and more intense due to human-induced climate change”.
Britain beat its all-time high on 25 July when 38.7C (101.66F) was recorded in Cambridge.
Germany, Belgium and the Netherlands also set national records during that intense hot spell.
In June, France also recorded a new all-time high of 45.9C (114.4F) after another heatwave.
Shortly after, scientists for the World Weather Attribution said it was made five times more likely by climate change.
Researchers who authored its latest report stressed that heatwaves which last several days can “pose a substantial risk to human health and are potentially lethal” – particularly to the elderly and people living in cities.
“Heatwaves are known to increase mortality, especially among those with existing respiratory illnesses and cardio-vascular disease,” the report says.
The UK’s Met Office said this week that the country’s 10 warmest years on record had all been since 2002.
There have been more than 230 studies examining whether climate change is making particular weather events more likely.