One of the warmest Winter Olympics in history is getting warmer.
Temperatures reached the low-60s today in Sochi, and they're expected to stay there on Thursday and Friday. For some perspective, the weather in the coastal resort is now roughly as warm as it was during certain days of London's Summer Games in 2012. According to Forecast.io, the average temperature for the Sochi Olympics so far has been 45 degrees Fahrenheit, three degrees lower than the average during the previous Warmest Winter Olympics Ever: the 2010 Vancouver Games. But Sochi's highs have been higher than Vancouver's. And Vancouver's daily average never rose above 50 degrees, while Sochi's has surpassed that level several times.
All this creates issues. Like mush, which the American snowboarder Shaun White cursed shortly before failing to medal in the relatively cool mountains outside Sochi. Organizers are now compensating for the lack of hard snow with a wintery mix of chemicals, water injections, and strategic snow reserves. Hundreds of snow cannons stand ready in case of emergency.
This week, however, over 100 Olympians, 85 of them American, blamed more than warm weather for the poor conditions. The real culprit, the athletes said in a statement, is climate change—and world leaders better do something about it during climate talks in Paris next year. "Snow conditions are becoming much more inconsistent, weather patterns more erratic, and what was once a topic for discussion is now reality and fact," U.S. cross-country skier Andrew Newell wrote. "Our climate is changing and we are losing our winters."
To support his argument, Newell cited a recent study with an alarming finding: As a result of global warming, as few as six of the previous 19 Winter Olympics host cities—less than a third—will be cold enough to hold the Games by the end of this century. "In a substantially warmer world, celebrating the second centennial of the Olympic Winter Games in 2124 would be challenging," the report's authors wrote. You can't ski safely or successfully in slush.
The study, conducted by the University of Waterloo in Canada and the Management Center Innsbruck in Austria, calculated the average daytime high in past Winter Olympics locations in February, the month in which the Games are nearly always held, and plotted the results in three-decade increments. They found that temperatures have been steadily increasing from 32 degrees Fahrenheit between the 1920s and 1950s to 46 degrees so far this century (the first Winter Olympics were held in 1924, in France). Sochi's weather conforms with this pattern.
In forecasting the future of the Winter Olympics, the researchers made certain assumptions. They used international climate data and projections for greenhouse-gas emissions to generate low and high estimates for the amount that average February temperatures will increase in former Winter Olympics host cities over time. The baseline is the average February temperature at these locations between 1981 and 2010. The authors, in other words, are predicting that, based on conservative estimates, the temperature in, say, Turin, Italy in February 2050 will increase by three degrees because of climate change.
The researchers fed all this data into an assessment of which of the past 19 Winter Olympics cities will be cold enough to hold the Games in the mid- to late-21st century. They defined a suitable climate by considering factors like "the probability that daily minimum temperatures at the main competition elevation would remain below freezing," and "the probability that a snowpack of at least 30cm can be maintained at the higher elevations of alpine events, through both natural snowfall and snowmaking."
The results are below. By mid-century, according to pessimistic projections, only 10 of these cities will be climatically suitable to host the Games. By the end of the century, the field will be winnowed down to just Albertville, Calgary, Cortina d'Ampezzo, St. Moritz, Salt Lake City, and Sapporo.
Note also that Sochi is listed as cold enough for the Games right now, meaning the International Olympic Committee didn't necessarily make a mistake in awarding this year's Olympics to the subtropical, Black Sea city. In fact, the authors suggest that new technologies like artificial snowmaking have made the IOC more willing to choose warmer host cities (the IOC explicitly states that it considers how countries that submit bids plan to adapt to global warming). But the researchers are suggesting that Sochi 2054 probably won't be happening.
The National Oceanic and Atmospheric Administration has taken this analysis one step further, mapping the average minimum temperatures (overnight lows) for January and February from 1911 to 2011 for all Winter Olympics host cities. The shades of red represent average minimum temperatures above freezing, and the shades of blue represent average minimum temperatures below freezing. The second panel zooms in on Europe, and you can see that several of the cities identified as climatically suitable for future Games, including Calgary, Cortina d'Ampezzo, and Salt Lake City, are located in below-freezing zones.
NOAA's map suggests that northern China and parts of Russia could be better suited to host the Winter Olympics in the future (Pyeongchang, South Korea, where the 2018 Games will be held, looks dicey, with temperatures currently in the 40s). But the University of Waterloo's Daniel Scott, the lead author of the report, says that the geography of the Winter Olympics might not necessarily shift. Instead, the nature of the Games might change, as it always has.
Vancouver, for instance, could host the Games again, but this time they'd have to hold skiing and snowboarding competitions at a higher elevation in the Rockies. The elevation of Germany's Garmisch-Partenkirchen won't be high enough for the outdoor portion of the Games, but it could co-host the Olympics with a country like Austria or Switzerland. "That's a different model than the Games have ever been," Scott says. "It's always been one country showcasing their culture, their society to the world."
But in a warmer world, that model may no longer be sustainable.
Top image: Workers construct Olympic rings during a snowstorm in Krasnaya Polyana, near Sochi, on January 24. (Reuters/Alexander Demianchuk)
This post originally appeared on The Atlantic.