Cross-country skiers at the 2014 Winter Olympics in Sochi, Russia. Richard Heathcote/Getty Images

Distill the upcoming Winter Olympics in Pyeongchang, South Korea, to their essence and you get 15 sports that involve gliding on snow or ice. Because of climate change, though, by 2050 many prior Winter Games locations may be too warm to ever host the Games again.

By midcentury, nine former Winter Olympics sites may not be reliably cold enough for the Games.

A team of researchers, led by Daniel Scott, a geography professor at the University of Waterloo in Ontario, came to that conclusion by taking climate data from previous Winter Games locations and applying climate-change models to predict future winter weather conditions.

The research, originally published in 2014, was updated this month to include the Pyeongchang Olympics, which begin Feb. 9, and the 2022 Winter Games in Beijing.

According to Dr. Scott’s research, using emissions projections in which global greenhouse gas emissions continue to rise through midcentury and global temperatures increase by 4 degrees Fahrenheit by 2050, nine of the host locations will be too hot to handle the Games. But that temperature increase won't be felt equally. Chamonix, France, the site of the first Winter Games, will have winter temperatures 5.4 degrees Fahrenheit warmer by midcentury.

Three former venues may also lack sufficient snow, even with artificial snowmaking.

Dr. Scott’s model factors in artificial snowmaking, but that has its limits. The technology involves pumping water through small nozzles under high pressure. When the water hits cold air it freezes almost instantly and turns into snow – but only if the air is cold enough.

“You’re relying on cold air to do the refrigeration for you,” Dr. Scott said.

When the temperatures are above freezing, as they were during the 2010 Winter Games in Vancouver and the 2014 Winter Games in Sochi, you have to turn to more extreme measures.

In Vancouver, which melted under one of its warmest winters on record, organizers brought in 1,000 bales of straw and covered them with a mix of artificial snow and natural snow hauled in from higher elevations to cover the bare ski slopes.

When shortages of cold and snow are combined, four former venues are likely to be unreliable hosts by midcentury. Five more will be risky.

Nagano, Japan Sapporo, Japan Beijing, China Pyeongchang, South Korea Vancouver, Canada Squaw Valley, Calif. Calgary, Canada Salt Lake City, Utah Sochi, Russia Lillehammer, Norway Oslo, Norway Lake Placid, N.Y. Sarajevo, Yugoslavia Eight host locations in Austria, France, Germany, Italy and Switzerland Four not reliable or higher risk Nagano, Japan Sapporo, Japan Beijing, China Pyeongchang, South Korea Squaw Valley, Calif. Vancouver, Canada Calgary, Canada Salt Lake City, Utah Lillehammer, Norway Sochi, Russia Oslo, Norway Lake Placid, N.Y. Sarajevo, Yugoslavia Eight host locations in Austria, France, Germany, Italy and Switzerland Four not reliable or higher risk Pyeongchang, South Korea Sochi, Russia Not reliable Squaw Valley, Calif. Vancouver, Canada Garmisch-Parten- kirchen, Germany Sochi, Russia Higher risk Innsbruck, Austria Chamonix, France Grenoble, France Oslo, Norway Sarajevo, Yugoslavia Reliable Lake Placid, N.Y. Salt Lake City, Utah Calgary, Canada Beijing, China Albertville, France Cortina d’Ampezzo, Italy Turin, Italy Nagano, Japan Sapporo, Japan Lillehammer, Norway Pyeongchang, South Korea St. Mortiz, Switzerland

In Sochi, whose mild climate made it an unusual choice for the Winter Games, organizers banked snow from the previous winter, storing it in shady places and covering it with insulation.

Both locations also used technology that involves embedding pipes with dry ice in the sites for aerials and moguls skiing. The technique supposedly preserves snow for up to two days by cooling it from the bottom up.

Despite these efforts, athletes at both Games complained of poor snow that they said led to unfair conditions.

Skiers, for example, may consider a competition unfair when shifting conditions make a course faster or slower depending on when the skier races. At Sochi, snowboarders complained that the half-pipe was dangerous because of bumps and sugary snow that can slow down riders when they should be gaining speed for maneuvers that involve launching as much as 20 feet above the half-pipe’s 22-foot top edge. During the event’s qualifying runs, more than half of the athletes fell.

A hockey game at the 1928 Winter Games in St. Moritz, Switzerland, lefttop, and the United States hockey team facing Canada at the 2010 Winter Olympics in Vancouver. Alfred Gross/ullstein bild via Getty Images; Todd Korol/Reuters

In the past, Olympic organizers have dealt with the vagaries of weather by bringing events indoors. Skating events were once held outside, for instance. But you can’t move the mountains required for the giant slalom or the 50-kilometer course for one of the men’s cross country ski events indoors.

Even in a warming world, some regions will still have cold places. But the number of possible Winter Olympics locations will decline. In the future, the Winter Games might rotate through a handful of the same cities.

At the same time, the warming climate affects not only the locations of the Olympics, but also the ability of athletes to train. In the United States, some ski locations are forecast to see seasons 50 percent shorter by 2050 and 80 percent shorter by 2090.

That will complicate life for elite athletes, but they can at least travel to find snow.

The repercussions are potentially much more serious for young athletes getting a first taste winter sports. What will happen to the pipeline that feeds elite sports programs when the local ski hill, or the frozen pond where kids play hockey, disappears?