In 2003, France experienced a heatwave that had lasting effects, including the deaths of thousands of people and the collapse of the health system. Could a similar scenario unfold during the Paris Olympics?

Although it will be at least April before we know for sure, researchers are warning that this summer could see a heatwave worse than the one in 2003. If so, the catastrophic scenario could be repeated and even surpassed, as the high temperatures caused by global warming could exceed all known records. A heatwave much worse than the one in 2003 during the Paris Olympics could occur. It would be a catastrophic scenario, and the possibility exists because of climate change, warn researchers, a problem of which the organisers say they are "fully aware". The scientists set out to calculate the worst possible heatwave over 15 days in Paris, from 26 July to 11 August 2024.

"The motivation from the outset was based on the observation of the 2003 heatwave, which surprised everyone with its magnitude" and which "no one thought possible before it happened," explains Pascal Yiou of the Laboratory of Climate and Environmental Sciences (LSCE), lead author of the study published in the journal Npj Climate and Atmospheric Science. 21 years ago, during the tragic heatwave, hospitals were overwhelmed by a surge of patients, resulting in an estimated 15,000 deaths. For nine days in a row, daytime temperatures in Paris exceeded 35°C, with little cooling at night. Is it possible to beat the 2003 average? "Temperatures exceeding the 2003 record by about 4°C" in Île-de-France "are possible," the article concludes.

"In 20 years, the climate has changed and the idea was to warn the authorities that something significantly much worse than 2003 could happen, which is possible," stresses Pascal Yiou.

Asked by AFP, the Olympic organisers claim to be "fully aware of the impact that climate change can have on the competitions." "Heatwaves and extreme weather conditions are hypotheses that we must fully anticipate to take the necessary measures," they said. The organisers, who are working with Météo-France and Santé publique France, are using historical data for each venue. For their study, the researchers carried out a worst-case scenario simulation based on the climate models used by the IPCC (Intergovernmental Panel on Climate Change, commissioned by the UN). For such an extreme heatwave to occur, a combination of a stable anticyclone and a meteorological phenomenon known as a 'cold drop,' capable of pumping very hot air from the Sahara to France, would be necessary, they specify.

This is not a weather forecast for next summer. Météo-France only publishes "broad trends" for three months, and it will be necessary to wait for a somewhat vague indication for July. "We won't know in April if there will be heatwaves in July, but we will have a trend in a scenario close to, below or above normal," Météo-France told AFP.

Events could be rescheduled

Some events, analysed on a case-by-case basis, may be postponed due to climate issues related to extreme heat, such as the women's marathon, which was brought forward due to high temperatures. The 2021 Tokyo Olympics were the hottest on record since 1952, but the impact was limited as they were held without spectators due to the prevailing Covid-19 restrictions.

Although many events are relatively easy to run even in high temperatures, with the use of air conditioning on the track and in the stands, especially those held outdoors. In all cases, excessive use of energy to lower temperatures would be an option, which is contrary to the goal of hosting more sustainable and environmentally friendly games.

Would it not be possible to change the dates if the Games were held in the northern hemisphere? Moving them to June, September or even October would obviously be more temperate and better for the environment, as well as for the athletes and the fans.

FIFA has already implemented this for the 2022 World Cup in Qatar and is likely to do so again for the 25th edition in Saudi Arabia in 2034. As for Paris 2024, its fate is sealed and will largely depend on Mother Nature, which has been so attacked by man, and any measures that can be taken on the fly. In the future, it will be necessary not only to preach but also to adapt and change, rather than to complain.