The risk of a heat wave looms over the Paris Olympics. 

The last Summer Olympics in Tokyo were the hottest in history, but a new report on heat risks at the Paris Olympics warns that this year could be even hotter. 

Since the last time Paris hosted the Summer Games, in 1924, the average temperature that time of year has risen about 3.1 degrees Celsius (or about 5.5 degrees Fahrenheit).

Heat waves have been increasing in frequency and intensity in Paris. The "urban heat island effect," whereby urban areas tend to be warmer than rural areas, has only exacerbated the issue in the Paris region. 

A Parisian summer can see temperatures reaching 90 degrees Fahrenheit. On July 25, 2019, Paris reached its all-time high record temperature of 108.7 degrees Fahrenheit, almost exactly five years to the date before the summer Olympic Games are scheduled to begin. 

As the world warms due to climate change, athletes and scientists are expressing concern of what this means for the future of the height of sports competition occurring at the height of summer.  

Last summer in France over 5,000 people died from the sweltering heat.

"I am still just surprised at the timing of these Olympics," says Kaitlyn Trudeau, a senior research associate for climate science at Climate Central. "We have seen such deadly heat waves in this exact location at this exact time, many times in recent history." 

The dangers for athletes competing and training in these conditions can range from heat cramps to collapse from heat stroke. 

James Farndale, a rugby player who has represented both Scotland and Great Britain, says he trained in heat chambers at a training base in Scotland prior to competing in the Dubai Seven. He warned that athletes are not conditioned to hold back, even in conditions that are unsafe. 

"It is not in an athlete's DNA to stop and if the conditions are too dangerous I do think there is a risk of fatalities," says Farnale. 

The Tokyo Olympics had athletes vomiting and even fainting at the finish line with almost one in every 100 athletes suffering from a heat-related illness. 

One athlete at the last summer Olympics raised concerns of heat exhaustion mid-match. Daniel Medvedev, a top-five ranked men's tennis player, took a number of medical time-outs during his tennis match before being asked if he can continue playing. 

"I can finish the match but I can die," Medvedev replied. "If I die, are you going to be responsible?"

The rise in not only temperatures but humidity adds to the risk of heat stroke, according to Trudeau, who says that it makes it more difficult for bodies to sweat to cool down and regulate core temperatures. 

Paris Olympic organizers say that heat risks have been factored into scheduling outdoor sports, including scheduling marathon and triathlon events in the early morning. There are contingency plans in place to reschedule events depending on heat and humidity level each day. Each decision will be made on a sport by sport basis with the International Federation according to a statement to CBS News from a Paris 2024 spokesperson. 

These efforts to stay safe from the extreme heat will extend beyond the athletes to include the fans, volunteers and workers. Spectators will be allowed to bring in their own water bottles. Free water refilling points will be available throughout each venue at a ratio of one for every 300 spectators.

Paris 2024 has promised to deliver an Olympic Games that are "more responsible, more sustainable and more inclusive." The organizers emphasized a focus on reducing the carbon footprint by using pre-existing venues and utilizing the metro and bike lanes to minimize travel emissions. 

One climate mitigation effort has raised concerns from athletes. The Olympic Village will not have any air conditioning. A water-based cooling system will be used instead, but some athletes are bringing their own air conditioners. The U.S., U.K., Australia, Denmark and Italy are all bringing their own A.C. with the Australian Olympic Committee's calling its decision to install air conditioners in its athletes' rooms "strategic for high performance" according to The Guardian.

"We designed these buildings so that they would be comfortable places to live in in the summer, in 2024 and later on, and we don't need air conditioning in these buildings because we oriented the facades so that they wouldn't get too much sun during the summer, and the facades, the insulation is really efficient," Yann Krysinski, who is in charge of the delivery of venues and infrastructure at Paris 2024, told Reuters.

For those countries interested, the Olympics will provide "lower-emitting mobile cooling units" available for rent, according to a Paris 2024 spokesperson. 

The dedication to climate-friendly games does not seem to extend to the sponsor list. The sponsors of national Olympic and Paralympic teams include British Gas for Team Great Britain; Hancock Prospecting, a mining company, for the Australian Olympic Team; and Reliance Industries Limited, a petrochemical conglomerate, for the Indian Olympic Association. 

Climate activists are encouraging athletes to speak out about their concerns about heat risk and climate change at large. 

"Something that I'm really keen for sport to do here is be an alarm bell in this space because of the implications of a two- or three-degree warmer world on millions and billions of people's lives," says Farndale. 

In:
• Paris
• Climate Change
• Olympics