Olympic snowboarder Matt McCormick started noticing changes in the mountains a few years ago.

"The problem with that is it makes things like avalanches way more prominent and the mountains just become way more dangerous," he says. "Snowboarding is already a dangerous sport, and it makes it more dangerous, which is not exactly what we need."

From the Winter Olympics to ski holidays, snow sports are under threat because of rising global temperatures. One study updated in 2018 predicted that hosting the Games again at nearly half of the previous venues would be too risky by 2050.

"From a competitive point of view it is a worry, but even competitive snowboarders would say that's only a small corner of it," McCormick says.

"Nobody's as fussed about whether there will be an Olympics in 2026, but whether there will even be a mountain to ride on in 2030."

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Danger on the mountain

Robbie Phillips, a professional climber, is also concerned about changing conditions in the mountains.

He climbed the north face of the Eiger in Switzerland in the summer of 2015, when there was next to no ice. When it was first conquered in July 1938, it was a full winter-style climb.

Phillips says the window for winter climbing during the year has massively narrowed, which creates its own problems.

"Especially in the UK, a lot of people travel quite a long distance to go winter climbing," he says. "Because conditions are becoming more fickle, people are more inclined to risk just getting out climbing when the conditions aren't perfect. That's potentially a disaster.

"It's up to the individual to make the decision, but because there are fewer good days, people are more likely to take risks just to get out there and climb. As a result, there's probably more accidents happening."

Resorts face challenging future

Scotland's five winter resorts are all below 2000m, which means they are at greater risk of less snow as temperatures rise.

A report by the Climate Coalition predicts a 2-4C increase in temperature could cause a 60% reduction in winter snowfall rates by the 2080s. Some current forecasts have the world heading for a 2.7C rise in temperatures.

Ski resorts in Scotland are already facing challenges due to less predictable winters, with Snowsport Scotland's national facilities strategy suggesting all five resorts should invest in further snow-making facilities.

But artificial snow requires huge amounts of water, which has its own environmental impact, as does the large amounts of energy required for the process, sometimes from diesel generators. It is a vicious circle.

Cairngorm Mountain (Scotland) Limited, the company which runs the resort on the mountain of the same name, told BBC Scotland they recognise the impacts of artificial snow, but are working to make it "more sustainable".

The ski industry is worth £30m to the Scottish economy and supports 634 jobs, mostly in rural communities such as Aviemore. A lack of snow on the mountains puts entire towns' prosperity at risk, then there is an accessibility issue too.

Winter sports are already expensive, and cheaper resorts below 2000m losing snow means higher, more exclusive destinations in Europe will be the more reliable options only for those who can afford them.

Athletes leading the fight

While resorts and governing bodies are getting to grips with the existential threat facing winter sports, it is the athletes who are leading the fight back.

Protect our Winters (Pow), is a charity originally set up in the United States but now with a global reach which tries to harness the voice of athletes to pressure governments and businesses to do more on climate change.

A big part of that is education. Athletes are put through a carbon literacy course so they have the confidence to engage with their fans, sponsors and politicians on environmental issues.

"We work with our community to educate them about the different problems," Pow's UK general manager Lauren MacCallum explains. "Whether that's around local authority pensions, North Sea extraction, or energy and finance.

"If we can get our community and industry aware, educated and empowered to act on these issues then we can squeeze it on the policy. I guess why we see that as being an effective model is, if you go and speak to ministers and it's just the same climate voices all the time, it becomes easier to ignore every single time."

Both McCormick and Phillips work with Pow, and agree the best way they - and others - can force change is through the democratic process of voting, getting in touch with your MP, and engaging with others.

That's as well as making some changes to their own lives, including where they might choose to spend or invest their money. But as athletes who travel by plane to compete and move around the country, they are often met with claims of hypocrisy.

"It's a challenging thing to deal with, because it happens fairly regularly," Phillips says.

"But I think rather than demonise people for individual actions we should be trying to encourage people to make systemic change - calling out governments and businesses to fight for climate change [issues]."

McCormick concurs. "I totally understand where that's coming from. But the problem with that is, if you follow that train of thought to its logical conclusion, everyone should just do nothing.

"If everyone sits around and point fingers, we wont get anywhere. So it's really important people can do what they perceive they can."

Despite the challenges, McCormick is still positive his sport can be salvaged.

"I'm definitely hopeful," McCormick says. "I'm pretty certain it'll maintain, but it's going to get harder. That's what scares me is how much harder it's going to get for me in the short term, and future generations in the long term."