It is no longer important to use modelling to determine whether a heatwave was made more likely by climate change, say scientists, because it plays a role in all heatwaves today.

Every heatwave today was made more likely by climate change and there is no longer a need to wait for studies to tease out its role in individual extreme heat episodes, according to the scientist who pioneered such work.

Researchers usually caution against blaming specific extreme weather events on climate change. Heatwaves in China and Japan this week wouldn’t usually have been pinned on climate change before “attribution studies” to work out how likely the heatwaves are in a world with our changed climate and one without. Such studies have come of age in the past decade, led by Friederike Otto at Imperial College London, and can now be turned around in days.

However, Otto says, for heatwaves at least, we no longer need to wait before declaring climate change’s role. “I think we can very confidently now say that every heatwave that is occurring today has been made more intense and more likely because of climate change,” she says. While changes to land use might after affect the likelihood, she adds: “There is no doubt that climate change is really an absolute game changer when it comes to heatwaves.”

Nonetheless, she says studies will still be needed to know exactly how much more likely and intense heatwaves were made by climate change. “We shouldn’t stop doing attribution,” says Otto.

Read the full story on New Scientist.