The 2018 Winter Olympics will see athletes from a record-breaking 92 countries compete in Pyeongchang, South Korea. But winter sports face a double threat, from climate change and ageing populations

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Winter sports are under threat. The multi-billion dollar industry – the livelihood for many mountain communities – faces a double problem. The popularity of skiing and snowboarding is declining in the rich world and resorts are having to cope with a warming climate.

This luxury hotel is the birthplace of winter sports. In the 19th-century, Switzerland was a popular summer destination for English tourists. The owner of the Kulm at the time, Johannes Badrutt, wanted to fill his hotel all year round. So in 1864 he made a whiskey-fuelled wager with some English guests.

The Englishmen returned for Christmas and became so hooked on snow pursuits that they stayed for three months. Soon others followed, and winter holidays were born.

Along with their tweed suits and pinafores, the English guests brought their love of competition. With the post-war economic boom and the introduction of mechanised ski-lifts in the 1960s, winter sports soon became all the rage.

Fashionable ski-suits appeared on the slopes, and while the style of the time was questionable, the industry brought wealth to poor mountain valleys. But these days the outlook is darkening.

Skiers in rich countries are gradually leaving the sport and younger people are less inclined to take it up. Many head to cheaper, hotter destinations for winter sun.

In the last ten years the number of skiers in the world’s major-ski destinations has fallen. Locals here are worried. For St Moritz and other mountain towns like it, winter sports are essential to people’s livelihoods.

In the Swiss town of Davos, scientists have been measuring the amount of snowfall and the depth of the snow pack, for nearly a century. Even though there was a lot of snow in Davos this year, long-term trends show snowfall has been declining for decades.

And the depth of the snowpack has been thinning since the 1950s. Ski resorts have responded to the problem by investing heavily in snow-making machines. In some places, snow-making has allowed resorts to extend the ski season.

But in a warming climate, resorts will increasingly look like this. Many may close by the end of the century because they will not have enough natural snow and they will be too warm even to make artificial snow.

Take this region of the eastern Alps. Scientists calculate that if temperatures increase by two degrees, about 15% of resorts may have to give up on skiing. If temperatures rise by four degrees, 60% may be forced to close.

The big hope for winter sports now l