This blog appears in the In-Depth Report Science at the Sochi Olympics

Climate change poses a well-documented threat to ecosystems and human populations worldwide. But as the inexorable warming trend continues, it’s also endangering the future of winter sports. In a new report published in January by the University of Waterloo, researchers analyzed the suitability of past locations of the Winter Olympics since 1981 based on planet warming scenarios likely to result from high- and low-carbon emissions over the coming decades. Even in a low-emissions scenario, they found that six of the 19 sites would be inappropriate to host the Olympic Winter Games by the 2080s because temperatures would likely be too elevated. Another three sites were designated as “Climatically High Risk.” Under a high-emissions scenario, over two-thirds of the sites would be poor bets by the 2080s.

The danger to winter sports has not gone unnoticed by athletes. In an effort to get Olympians on record discussing climate change, a group of students from Yale University’s School of Forestry and Environmental Studies have traveled to Sochi to interview athletes about their views on climate change and to gather their personal observations of the changing conditions where they train and compete. Calling themselves “Team Climate,” the students (whom I know personally from my time at the school) have been blogging about their interviews with Olympians including Andy Newell, Hannah Kearney, and Arielle Gold.

“We staged this campaign at the Olympic Games because we believe they are the perfect forum to open a dialog about climate change with a new audience,” Diana Madson, one of the members of Team Climate, writes in an email. “The Olympics offers an opportunity to highlight the natural connection between winter sports and climate change.” Although the group has had their share of difficulties, including a long-standing hotel reservation that had vanished upon arrival, their experience has become something more than just fulfilling initial activist aspirations. “The most fun has been getting to know these athletes on a personal level,” writes Taylor Rees, another member of the group.

Cross-country skier Andy Newell, in particular, has been one of the most outspoken Olympians on climate change. On Monday, he published an open letter calling for urgent action. Signed by over 100 other Olympians, including Ida Sargent and Sophie Caldwell, the letter calls for world leaders to take substantive steps to curtail emissions at the Conference of Parties to the UN Framework Convention on Climate Change, which will take place in Paris in late 2015.

In the letter, Newell details some of the changes that he has witnessed over his own lifetime, since his first time on skis in 1985. “Our climate is changing and we are losing our winters,” he writes. In his home state of Vermont, the winters have become inconsistent. And in an interview with members of Team Climate, Newell said, “There have been so many instances in the past 10 years where our early season competitions have been delayed or canceled due to lack of snow.”

Not all of the American Olympians are as gung-ho as Newell, however. Skier Hannah Kearney, who won a bronze medal in women’s moguls on February 8th, isn’t sure which side of the debate she falls on. “The huge climate change debate is complicated, and I don’t always know who to believe,” she said in an interview with Team Climate. But, she said, “Where I have noticed it most is on the glacier that we ski and train on… I have noticed that the glaciers are getting smaller and smaller every year.”

The use of anecdotes as evidence to prove (or disprove) long-term trends carries risks, however, even as it adds a more concrete dimension to the discussion of climate change. After all, climate skeptics often point to extreme cold weather or snowstorms as evidence against global warming. Climate scientists consistently dismiss such claims as expected variation within a long-term warming trend, or, in some cases, as further evidence of climate change. So Team Climate also backs up the changes that these Winter Olympians have observed with links to scientific reports and studies.

For example, they draw from the Intergovernmental Panel on Climate Change report that notes that in the Northern Hemisphere, the period from 1983 to 2012 was likely the warmest 30-year span in the last 1400 years. And as for snow cover, it has decreased by about 12 percent every decade for the last thirty years, according to the report. And they cite a study suggesting that out West, snow depths could decline drastically; another report they cite says that the Northeast snow season could be cut in half.

Will world leaders listen to Olympians more than they have to the repeated calls of other groups for decisive action on climate change? We may have to wait until the Paris conference in 2015 to find out.