The Valencia region, in Spain, is affected by the worst floods in half a century, raising the question of the possibility of such a phenomenon in France.
The floods which have affected the south-east of Spain since Tuesday October 29 have caused, according to a latest provisional report which is expected to increase further, at least 158 deaths. Dozens of people are still missing. This is the worst human toll in nearly fifty years and the floods of 1973 which left 300 dead.
A drama which follows a Mediterranean episode, usual in the fall, associated with a cold drop phenomenon, a pocket of cold air at high altitude causing a disturbance in the weather. Together, these two climatic events cause heavy rains, therefore flooding, deaths and considerable damage. Images of chaos and a question: can such a phenomenon occur in France?
What risks in France?
As in the Valencia region, all areas located on the edge of the Mediterranean can be affected by Mediterranean episodes, in Spain, France or Italy. Experts also agree on the fact that while these phenomena are common, especially in the fall, it is their intensity that has increased tenfold due to climate change. The rise in the temperature of the Mediterranean Sea – which is around 20 degrees off the coast of Valencia – generates more humidity favors stormy episodes by encountering a famous “cold drop”.
In France, regions such as the Cévennes or Corsica are more exposed to such climatic phenomena. Recently, the passage of the Kirk depression on October 9 and 10, then the floods the following week, were sad illustrations of this.
“The entire Mediterranean arc is affected, including France,” Serge Zaka, an agro-climatologist specializing in the impact of climate change, explains to La Dépêche. “Because of global warming, these weather phenomena will increase in intensity. This is not a projection, but an observation.”
A “dramatic” cocktail, according to Jorge Olcina, professor of climatology at the University of Alicante interviewed by AFP. When they reach such magnitude, cold drops can have effects “very similar” to those of a “hurricane”, insists this researcher.
Flood in Spain: what weather phenomena caused this disaster?
“The result of 30 years of climate inaction”
“For 40 years, exposure and vulnerability have increased and for 40 years, disasters have followed one another,” laments on X Magali Reghezza, geographer specializing in natural risks, disaster prevention and adaptation to climate change.
“We are paying for the legacies of decades of neglect. And we are also paying for the result of 30 years of climate inaction,” she adds.
In Spain as in France, urbanization and land artificialization are also aggravating factors for such climatic phenomena. In the same way, high urban density in Mediterranean areas, such as in Valencia in Spain or, on the French side, in the South-East, can contribute to increasing the risks of fatal floods. In Spain as in France, these regions are plagued by drought summers, causing the soil to dry out and make it difficult to absorb autumn precipitation.
“Whatever the adaptation plans, as long as the Earth warms, we are condemned to suffer more and more disasters,” concludes Magali Reghessa.
And added: “Despite technical progress, beyond a certain level of warming, these territories will be uninhabitable (…) Only mitigation, with the achievement of net zero CO2 emissions will stabilize warming and will allow adaptation.”
François Gemenne, professor at HEC and member of the IPCC, calls on our colleagues at RTL to “draw very important lessons from what has just happened in Valence both in terms of alerting populations and evacuating populations, but also in terms of land use planning management.
Lucie Valais Journalist BFMTV
