Before you know it, most cities will be too hot to host the Summer Olympics

In 70 years only a handful of cities will be cool enough to host the Summer Olympics, according to research published in the journal the Lancet. 

According to the climate models the researchers used, if the Earth keeps warming at its current rate, only eight cities outside western Europe and three cities in North America (San Francisco, Calgary and Vancouver) will be suitable hosts by 2085. All of Latin America and Africa will be too hot. Istanbul, Madrid, Rome, Paris, Budapest and Tokyo — all of which were bidders for the 2020 or 2024 Olympics — would be too hot to host them by 2085. 

The researchers used two climate models to project how temperature, humidity, heat radiation and wind would change over the next century. 

Here's how the researchers figured out the cutoff: Only cities with more than 600,000 people and elevations under one mile were considered. A city didn't make the cut for 2085 if there was more than a 10% chance it would have to cancel the Olympic marathon (a popular outdoor event at the Olympics) at the last minute due to heat concerns. That's also the cutoff used for the Winter Olympics right now. If a city has more than a 10% chance of not getting enough snowfall for the games, it can't be a host.

"If you're going to be spending billions of dollars to host an event, you're going to want have a level of certainty that you're not going to have to cancel it at the last minute," study co-author Kirk Smith said in a statement. 

There are workarounds of course, like hosting the games indoors, but the research helps illuminate some of the ways that climate change may disrupt our lives. 

"Climate change is going to force us to change our behavior from the way things have always been done," Smith said. "This includes sending your kids outside to play soccer or going out for a jog. It is a substantially changing world. If the world's most elite athletes need to be protected from climate change, what about the rest of us?"

And if 2085 is too hot for the Summer Olympics, just imagine what the Winter Olympics could be like.