France’s record-breaking heatwave ‘made up to 3C hotter by climate change’

The record-shattering heatwave that baked much of northern Europe last month was likely between 1.5 to 3 degrees Celsius hotter due to manmade climate change, an international team of scientists said on Friday.

France's record-breaking heatwave 'made up to 3C hotter by climate change'
Photos: AFP

The three-day peak saw temperature records tumble in Belgium, the Netherlands and Britain and the city of Paris experienced its hottest ever day with the mercury topping out at 42.6C on July 25th.

The ferocious heat came off the back of a similar wave of soaring temperatures in June, helping that month to be the hottest June since records began. 

READ ALSO IN PICTURES: How France coped with record temperatures

Scientists from the World Weather Attribution team combined climate modelling with historical heatwave trends and compared it with in situ monitoring across the continent. 

They concluded that the temperatures in the climate models were between 1.5-3C lower than those observed during the heatwave in Europe.

“In all locations an event like the observed would have been 1.5 to 3C cooler in an unchanged climate,” the WWA said, adding that the difference was “consistent with increased instances of morbidity and mortality.”

Global warming also made the July heatwave in some countries between 10-100 times more likely to occur, compared with computer simulations.

Such temperature extremes in northern Europe, without the additional 1C centigrade humans have added to the atmosphere since the industrial era, would be expected on average once every 1,000 years.

“Climate change had therefore a major influence to explain such temperatures,” the WWA said. 

The July heatwave caused widespread disruption, prompting train cancellations and emergency measures in many cities. Several heat-related deaths were reported, though a precise toll is likely to take weeks to materialise.

The June heatwave itself was likely made at least five times more likely by climate change, and was around 4C hotter than an equivalent heatwave a century ago.

“Models are very good at representing large-scale seasonal changes in temperatures,” said Friederike Otto, acting director of the Environmental Change Institute at the University of Oxford.

“On localised scales, climate models tend to underestimate the increase in temperature.”

Europe has experienced exceptionally intense heatwaves in 2003, 2010, 2015, 2017, 2018 and two this year, peaks consistent with the general warming trend: the four hottest years on record globally were the last four years.

Martha Vogel, a climate researcher at the Swiss Federal Institute of Technology in Zurich who was involved in the WWA research, said it was “virtually certain” that Europe's 2018 heatwave – which sparked widespread wildfires – could not have occurred without climate change. 

Vogel and the team in a study published last month found that just 2C of warming – levels aimed for in the Paris climate deal – would see a  2018 style heatwave happen every year.

“The five hottest European summers – 2018, 2010, 2003, 2016, 2002 – were all in this century,” she told AFP.

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South west France on red alert for flooding

Five areas in south west France have been placed on a red weather alert for flooding as storms lash the region.

South west France on red alert for flooding
Storms are moving in to south west France over the Pyrenees. Photo: Anne-Christine Poujoulat/AFP

Météo France has placed five départements in south west France – Pyrénées-Atlantiques, Landes, Hautes-Pyrénées, Haute-Garonne and Ariège – on a red weather alert for heavy rains and flooding.

Extremely heavy rainstorms have hit the area, with a band of storm clouds travelling along the Pyrenees, bringing the risk of avalanches in the mountains and flooding in lowland areas.

The neighbouring département of Pyrénées-Orientale is on orange alert, along with the principality of Andorra. In the north, Aisne is also on orange alert for heavy rain.

Heavy rain is expected to continue throughout Monday, gradually easing off towards the evening, although the flood alerts remain in place until Tuesday.