Météo-France published the second part of its synthesis on climate evolution in France, detailing new possible records of heat, rainfall, or drought, which could lead to human, ecological, and material disasters.
The French national weather service's report outlines a scenario where extreme climatic episodes will be much more frequent, including more intense heatwaves, less snow in the mountains, and widespread forest fires. Météo-France predicts that temperatures above 40 °C could occur every year in France, with local heat records up to 50 °C possible by 2050.
Météo-France warns that a +4 °C increase would lead to "ten times as many days of heat waves and tropical nights" in France, with the number of very hot days rising to an average of eight per year. By 2100, heatwaves could start as early as mid-May and, in the worst scenarios, will occur without respite from mid-May to the end of September, potentially lasting up to two months continuously.
The climate in France will be about 2 °C warmer by 2030 compared to the 19th century, with projections indicating +2.7 °C by 2050 and +4 °C by 2100. The warming trajectory aligns with current state policies and is part of the third national climate change adaptation plan adopted in 2023.
Droughts in France will multiply in summer and autumn, with the northern half experiencing four to five months of dry soils and Mediterranean regions over seven months by 2100, leading to "up to two extra months of dry soil." These levels of drought will have damaging consequences for agricultural yields and biodiversity, posing risks to drinking water resources, industrial and agricultural production, and natural environments. The drought that France experienced in 2022 will become a frequent event by 2100, with some droughts potentially lasting for several consecutive years. Ouest-France notes that episodes of drought lasting multiple years are possible, similar to the current lack of precipitation affecting Roussillon.
Forest fire risks will increase across the entire territory. Météo-France warned that a +4 °C increase would increase the risk of forest fires across France, with the risk of fire generalizing to all of France by 2100. Regions like the Loire and the Paris Basin could experience high fire risks at frequencies comparable to the Mediterranean coast today.
In the mountains, snow cover, essential for summer river supply, hydroelectricity, pastoralism, and winter sports, will face reduced snowfall at medium altitudes in winter and faster melting across all altitudes. Snow on the ground in average mountains will be limited to the heart of winter, from mid-January to mid-March, with continuous snow cover lasting no more than two months.
Météo-France states that while "dry winters are still possible," humid winters will dominate, with totals far exceeding current records, necessitating preparation for increased flood risks. Intense rainfall events will become more frequent, and authorities must anticipate the danger of floods caused by very high rainfall totals in a single day.
The report indicates that the number of tropical nights, where temperatures remain above 20 °C, will rise significantly. In Marseille, the number of nights exceeding 20 °C will increase from fewer than thirty nights per year between 1976 and 2005 to 88 nights by 2100, nearly three months of the year. On the Mediterranean coast, nights above 20 °C will represent up to a third of the year (100 to 120 days) by 2100.
Health impacts are also a concern. In 2022, France experienced its hottest summer on record, contributing to nearly 5,000 deaths due to extreme heat. Météo-France expects five times more heatwave days by 2050 and ten times more by 2100, intensifying the threat to human health.
"The idea of this work is not to frighten the population but to produce data usable by adaptation actors," explained Jean-Michel Soubeyroux, Deputy Scientific Director of Climatology at Météo-France. He emphasizes the importance of preparing for a climate with "more severe extremes," noting that "this risk will be multiplied by two for the Southeast by 2100."
The report underscores the need for action to mitigate these severe climate changes. Davide Faranda, climatologist and research director at CNRS, warns: "It's another country that is being described to us. The extremes will be so intense and frequent that it will no longer be about living but surviving such upheavals." Adaptation will be impossible without damage, affecting all economic, social, and cultural activities.
The article was written with the assistance of a news analysis system.