The extreme heat of summer 2026 significantly impacted the mobility habits of residents in Île-de-France. A study by the Institut Paris Region (IPR) and the DRIEAT reveals a substantial reduction in the use of public transport and bicycles, particularly during the second week of heatwaves in June, when temperatures approached 41 °C.
Between June 22 and 28, 2026, transport usage declined compared to previous years. The observed drops varied by mode: buses saw a decrease of 17 to 28%, trains and RER by 10 to 16%, the metro by 10 to 13%, and the tramway by 9 to 15%. In Paris, bicycle trips fell by 10 to 20%. Road traffic on radial motorways also decreased by 3 to 5% during the hottest hours.
This overall reduction in travel is partly attributed to increased remote working, which appears to have limited the use of public transport. The decrease in road traffic in the late afternoon also suggests a renunciation of non-essential trips. Heatwaves in May and July 2026, however, did not show a significant effect on these transport modes.
Remote working is identified as a key adaptation strategy for extreme heat, although the study highlights inequalities among workers, as some cannot work remotely or adjust their hours. These constraints can exacerbate fatigue and stress during commutes, especially for those relying on public transport. Adapting mobility to climate change is therefore an environmental, organizational, and social challenge.
The study confirms the importance of better integrating heatwave episodes into the organization of travel in Île-de-France and encourages further reflection on transport adaptation strategies for extreme weather events.
