New report: Europe's heatwave amplified by 3 degrees due to human activity

2024-08-01

The researchers analysed historical weather data since 1979. "The main conclusion is that if similar weather conditions had occurred without human influence on climate, it would have been up to three degrees cooler during the heatwave. It would still have been warm, but we wouldn't have seen the high temperatures we saw now," says Gabriele Messori, rpofessor of meteorology.

The severe heatwave in mid-July, which caused several deaths in Greece and forced an airport to close, was amplified by up to three degrees due to human climate impact. This is the conclusion of a new report by a network of scientists - which also shows that heatwaves are now occurring earlier in the year.

- The main conclusion is that if similar weather conditions had occurred without human climate impact, it would have been up to three degrees cooler during the heatwave. It would still have been hot, but we would not have seen the high temperatures we saw now. When it's around 40 degrees, three degrees makes a big difference," says Gabriele Messori, professor of meteorology and climate researcher at Uppsala University.

He is part of the international Climameter research network, which has developed a new method to analyse the impact of climate change. Instead of comparing climate model simulations, the researchers analyse historical weather data since 1979, allowing them to filter out similar conditions compared between the periods 1979-2001 and 2001-2023.

Gabriele Messori, professor in meteorology.

In addition to heatwaves getting hotter, scientists have noticed that they are starting earlier in the year. Previously, similar heatwaves in Europe used to take place between July and August. Now they are more likely to start between June and July.

- Other studies have also shown that the number of warm nights is increasing. "This is something we will notice clearly here in Sweden, that we will have more so-called tropical nights when the temperature does not drop below 20 degrees," says Gabriele Messori, professor of meteorology.

Read the article in Dagens nyheter: https://www.dn.se/varlden/rapport-europas-varmebolja-forstarktes-med-3-grader-pa-grund-av-manniskor/