Climate change: What can we expect future French summers to look like?

With extreme heat, wildfires and hailstorms already recorded this summer, The Local asked French climatologist Françoise Vimeux about the likely effects of climate change in future years.

Climate change: What can we expect future French summers to look like?
A man walks on a flooded street in Louhans, northern France on July 17th, 2021. Photo: PHILIPPE DESMAZES / AFP.

Aside from the pandemic, the defining images of summer 2021 in Europe may prove to be weather related – from terrible wildfires in Greece to catastrophic flooding in Germany.

France has, so far, escaped the worst extremes but the country has already seen extreme heatwave and freak summer storms including hailstorms.

It’s common for France to experience storms following hot temperatures in July and August, even if the rainstorms came slightly earlier this year. But July saw 60 percent more rainfall than normal for the time of year.

“What’s exceptional is perhaps the fact that there were lots of examples of this type of event this summer,” Françoise Vimeux, climatologist at the Institut de Recherche pour le Développement (IRD – French National Research Institute for Sustainable Development), told The Local.

“Flooding is not just linked to the quantity of rain, it’s also linked to where the rain falls, whether it’s on a surface which can absorb it, which is the case in the countryside, or whether it falls in a town, where urbanisation means that concrete grounds cannot absorb water which then runs off.”

Impact of climate change

Although it is difficult to know whether a single event was caused by climate change, the heating of the planet has certainly played a role, according to Vimeux.

“We know that heating up the atmosphere and the oceans exacerbates incidents of intense rain,” she said. “Why? Because when the temperature is higher, surface water is more easily evaporated, meaning oceans, seas, flooded areas, lakes.

“And the atmosphere is more capable of retaining this water when the temperature is high. We know that when the atmosphere warms by one degree, it can hold 7 percent more water vapour. So when a weather event comes and cools down this air mass, there’s a lot more water which can fall.”

READ ALSO Forecast: Will summer in France ever get going?

So as the planet heats up, should we get used to wet summers in France?

“The climate projections show that, overall in France, we should expect less rain during the summer,” Vimeux said.

“However, that doesn’t mean there won’t be extreme rains over a very specific period and very locally, because our atmosphere will be loaded with water.”

This summer, the Aisne and Oise départements in northern France have been particularly hard hit by heavy rain, with France officially recognising a natural disaster in dozens of towns and villages following flooding in July. The Grand Est region was also badly affected.

Localised flooding

Vimeux offers the example of the regular épisodes cévenols (Cévennes episodes) in the south of France at the end of summer, “where the Mediterranean Sea is very warm so the water evaporates easily and accumulates in the atmosphere, and when there is atmospheric circulation which brings this water in towards the land, and the Cévennes mountain range, this air cools down and a lot of water falls.”

According to the climatologist, these episodes could become more extreme in the decades to come, with up to 20 percent more rain over a number of hours or over the course of a day, while the summer in general will be drier than it is now.

IN PICTURES: French town hit by freak June hailstorm

Which would not be good news for French farmers: “Intense rain is not always very useful for agriculture, because it doesn’t have the time to seep in, it often runs off, especially if it falls on dry ground. So short and intense spells of rain are not necessarily what is going to save agriculture in a context of drought.”

A recent report from France’s High Council on Climate showed that the soil could be “much drier” across almost the entire country by 2055, compared to 1970.

Image: Haut Conseil pour le climat. Yellow areas represent no change from 1970, light orange means the soil will be “slightly drier”, dark orange means “moderately drier”, and red areas will be “much drier”.

On the other hand, Vimeux added, “Projections show that we should have a bit more rain in the winter, but winter rains in France are not storms, but rather rain that falls slowly, allowing us to feed the groundwater tables, so that’s a good thing.”

Multiple dangers

Rising sea levels could also lead to a greater risk of flooding in years to come, particularly along the Atlantic coast. “When there is a storm, the low pressure system means there’s a slight rise in sea levels. Of course, if in a century’s time the sea is already one meter higher, a very small storm would do as much damage as a large storm today.” Vimeux cites the case of Storm Xynthia in 2010, “which brought about a rise of 1.6 metres at La Rochelle”.

A car stuck in water on July 15th, 2021 near the flooded banks of the Ardre river in Fismes, eastern France. Photo: FRANCOIS NASCIMBENI / AFP.

READ ALSO French winemakers count cost of ‘worst freeze in decades’

The kind of storms we’ve seen this year aren’t the only danger to France’s climate – the mainland is also vulnerable to heatwaves.

“We really are an area which can be subject to heatwaves in the summer which will be more frequent, longer, more intense, and we even know that they could arrive earlier in the summer and also slightly later.”

The south of France is particularly vulnerable as well as large cities, according to Vimeux. “Certain cities are not at all adapted for us to feel comfortable during heatwaves, because there’s no greenery, there are lots of surfaces which absorb heat, like concrete and stone.”

Record temperatures

We have already seen the first consequences of this warming. The south of France experienced record temperatures in 2019, with more than 46C recorded in the Hérault département.

“It’s possible that by 2050, we will, over the course of a day or a few hours, reach the famous, mythical temperature of 50C during a heatwave,” Vimeux added. Earlier this week Sicily recorded a temperature of 48.8C.

“There are also areas which are becoming more vulnerable to fires, whereas they weren’t before, like central France.”

But is all of this inevitable?

“Our climate is more or less determined until 2050 because of human activities and the greenhouse gases we’ve already put into the air. But we can still act on the climate for the second half of the 21st century,” Vimeux said.

While certain changes could be “mitigated”, others are much more difficult to stop. “Oceans are a very slow component of climate change, and even if we stopped all of our greenhouse gas emissions today, sea levels would continue to rise over several centuries.”

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France gets help from EU neighbours as wildfires rage

Firefighting teams and equipment from six EU nations started to arrive in France on Thursday to help battle a spate of wildfires, including a fierce blaze in the parched southwest that has forced thousands to evacuate.

France gets help from EU neighbours as wildfires rage

Most of the country is sweltering under a summer heatwave compounded by a record drought – conditions most experts say will occur more often as a result of rapid climate change.

“We must continue, more than ever, our fight against climate disruption and … adapt to this climate disruption,” Prime Minister Elisabeth Borne said after arriving at a fire command post in the village of Hostens, south of Bordeaux.

The European Commission said four firefighting planes would be sent to France from Greece and Sweden, as well as teams from Austria, Germany, Poland and Romania.

“Our partners are coming to France’s aid against the fires. Thank you to them. European solidarity is at work!” President Emmanuel Macron tweeted.

“Across the country over 10,000 firefighters and security forces are mobilised against the flames… These soldiers of fire are our heroes,” he said.

In total, 361 foreign firefighters were  dispatched to assist their 1,100 French colleagues deployed in the worst-hit part of the French southwest.

A first contingent of 65 German firefighters, followed by their 24 vehicles, arrived Thursday afternoon and were to go into action at dawn Friday, officials said.

Among eight major fires currently raging, the biggest is the Landiras fire in the southwest Gironde department, whose forests and beaches draw huge tourist crowds each summer.

It had already burned 14,000 hectares (35,000 acres) in July – the driest month seen in France since 1961 – before being contained, but it continued to smoulder in the region’s tinder-dry pine forests and peat-rich soil.

Since flaring up again Tuesday, which officials suspect may have been caused by arson, it has burned 7,400 hectares, destroyed or damaged 17 homes, and forced 10,000 people to quit their homes, said Lieutenant Colonel Arnaud Mendousse of the Gironde fire and rescue service.

Borne said nine firefighting planes are already dumping water on the blaze, with two more to be in service by the weekend.

“We battled all night to stop the fire from spreading, notably to defend the village of Belin-Beliet,” Mendousse told journalists in Hostens.

On several houses nearby, people hung out white sheets saying: “Thank you for saving our homes” and other messages of support for the weary fire battalions.

“You’d think we’re in California, it’s gigantic… And they’re used to forest fires here but we’re being overwhelmed on all sides — nobody could have expected this,” Remy Lahlay, a firefighter deployed near Hostens in the Landes de Gascogne natural park, told AFP.

With temperatures in the region hitting nearly 40C on Thursday and forecast to stay high until at least Sunday, “there is a very serious risk of new outbreaks” for the Landiras fire, the prefecture of the Gironde department said.

Acrid smoke has spread across much of the southwestern Atlantic coast and its beaches that draw huge crowds of tourists each summer, with the regional ARS health agency “strongly” urging people to wear protective face masks.

The smoke also forced the closing of the A63 motorway, a major artery toward Spain, between Bordeaux and Bayonne.

The government has urged employers to allow leaves of absence for volunteer firefighters to help fight the fires.

Meanwhile, in Portugal, more than 1,500 firefighters were also battling a fire that has raged for days in the mountainous Serra da Estrela natural park in the centre of the country.

It has already burned 10,000 hectares, according to the European Forest Fire Information System (EFFIS).