Insee Première · August 2022 · n° 1918

One in seven people lives in an area subject to more than 20 abnormally hot days per summer in the coming decades

The most recent climate simulations confirm that in the summers of the next three decades, the number of abnormally hot days and nights will increase significantly. The regions of Auvergne-Rhône-Alpes, Bourgogne-France-Comté and Occitanie will be the most exposed.

Currently, 14% of the population lives in areas where there will be more than 20 abnormally hot days in summer. These high temperatures weaken the health of the most vulnerable people, especially the elderly. Because of their distribution over the country, the latter will suffer more from the effects of heat anomalies. The elderly have also a slightly higher population in coastal areas. Although all coastal areas are less affected by these heat anomalies, the Mediterranean coast is nevertheless the metropolitan territory exposed to the highest temperatures.

The regions most susceptible to abnormal heat are also home to nearly 1.2 million people living below the poverty line, sometimes in poorly insulated homes. Furthermore, those areas concentrate many jobs in construction and farming, which are particularly difficult to carry out in anomalous temperatures.