Cities Conduct Extreme Heat Drills: Can They Prevent Future Disasters?

On a sunny Friday afternoon in October 2023, approximately 70 children entered a cool, dark tunnel in southern Paris as part of the city’s preparation for its increasingly hot future. The tunnel, a section of the abandoned Petite Ceinture railway that encircles the city, maintains a constant temperature of 64°F (18°C), making it an ideal refuge from the potentially lethal heat outside.

Once underground, each child simulated the effects of extreme temperatures that could become reality in their lifetimes. Some pretended to suffer from food poisoning after a power outage spoiled meals, while others faked symptoms of carbon monoxide exposure from a faulty generator. Meanwhile, Red Cross workers raced to prioritize patients for overwhelmed hospitals. Around them, dozens of firefighters, city officials, and teachers worked to replicate the chaos and cascading impacts a heat wave of unprecedented duration and intensity might impose.

The organizers of the Paris at 50C exercise included children because they will bear the consequences of a warming world—and because they ask critical questions. Crisotech designed the drill to imagine what might happen if temperatures reached 122°F (50°C), a scenario scientists warn could occur by 2100.

The exercise combined live drills with a tabletop simulation to help shape a plan to protect Paris’ 2 million residents from extreme heat. Once limited to a handful of cities, these rehearsals are now spreading as local governments stress-test health services, emergency responses, and essential infrastructure before temperatures reach dangerous extremes.

Europe’s Urgent Call for Heat Preparedness

What Paris is rehearsing could soon confront cities across Europe. Governments are being urged to prepare for 5 to 6°F (2.8 to 3.3°C) of warming, a shift that could push Paris toward dangerously high summertime temperatures by the end of the century. Such heat poses a global threat: modeling suggests that by 2050, more than 1.6 billion people in nearly 1,000 cities could regularly face perilous conditions.

Heat waves are already straining hospitals, causing power outages, and paralyzing transit systems. In complex urban systems, even minor failures can trigger larger breakdowns. But as cities invest time and resources into these exercises, a critical question remains: Do they actually improve preparedness?

Paris’ Deputy Mayor on the Importance of Drills

It took Pénélope Komitès, Paris’ deputy mayor in charge of resilience, over 18 months to prepare a drill that lasted just two days. She emphasizes the necessity of such planning:

“It was very important for us to show people that heat waves are not just something we see on the TV, but something that can happen soon, and that we need to improve what we’re going to do.”

To inform the scenario, scientists at the Île-de-France Regional Climate Change Expertise Group, which advises city leaders on climate risk, modeled potential future conditions. Additional studies, including data from the Intergovernmental Panel on Climate Change (IPCC), provided further insights into the escalating threat of extreme heat.