Wouldn't it be a tragedy if your grandkids couldn't go skiing in the mountains?" asks Geordie Gillett, the owner of Grand Targhee, a low-key family-run resort nestled in Idaho's Teton Valley that currently enjoys some of the most plentiful natural snow in the world. "If we don't change the path we're on, that's a very real possibility."

While some short-term effects of global warming (combined with a recent El Niño cycle) have increased the number of storms and total amount of snowfall in certain high-altitude mountains in places like the southwestern U.S. and South America, that's essentially a false positive, and guys like Gillett – more realist than alarmist – have had to come to terms with this. According to a recent study commissioned by the city of Aspen, Colorado, if greenhouse-gas emissions continue at the current rate, by 2030 the ski season in many resorts across the continent and in Europe will have shrunk by 10 days or more. After that, things only get worse: The report paints a disquieting picture of snow falling later and melting earlier, with higher temperatures prohibiting even snowmaking. By 2050, any resort in the world below 5,000 feet in elevation will not have a natural snow season, and by 2100 – and maybe sooner – the only winter precipitation at what are now our resort areas will be in the form of rain.

"Climate change is the issue of our time," says Auden Schendler, the vice president of sustainability for Aspen Skiing Company and author of the book 'Getting Green Done: Hard Truths From the Front Lines of the Sustainability Revolution.' "There is nothing else in business, education, or religion as broad and threatening." But Schendler also thinks the ski industry and winter-sports communities are uniquely positioned to lead the public and private sectors toward meaningful change. "The ski industry is the perfect metaphor to explain climate change to society," he says. "When the CEO of a major ski resort lobbies Congress and visits the White House" – as Aspen's Mike Kaplan did earlier this year – "it's newsworthy."

But if global warming is the biggest issue facing his business, it isn't the only one. The overall economy of skiing is shrinking at an alarming rate. Michael Berry, president of the National Ski Areas Association (NSAA), outlined the industry's current state to resort owners at a recent conference. The data is grim: Annual skier days in the U.S. have been stagnant at around 50-60 million for the past decade; 83 percent of people who ski for the first time never try it again; and trend forecasting indicates that skier visits – 57.4 million in the 2008-09 season – will decline to 41.4 million by 2020 or 2021. "We need to talk strategically about how we bring people to the sport – how we grow it," Berry said.

The burden of a sagging economy, of course, is making things even more difficult. Because the heavily leveraged ski-resort business relies on real estate sales and capital investment to stay afloat, often operating in substantial debt, new resorts live and die by the Dow Jones. British Columbia's Revelstoke Mountain made headlines recently when its aggressive billion-dollar development plan was restructured after just one year at the same time as it defaulted on a $7.7 million land deal intended for a Nick Faldo-designed golf course; local rumors have the entire mountain resort teetering on the edge of collapse. Two other ambitious resort developments – the invitation-only Yellowstone Club in Montana and Tamarack Resort in Idaho – have already flamed out in recent years, the former due to the economy as well as alleged fraud and mismanagement, the latter because of the bursting of an old-fashioned real estate bubble.

According to the NSAA, of the 735 resorts in existence during the 1982-1983 ski season, only 471 remain today. Most of the absentees are the kind of mom-and-pop hills that defined the early ski experiences of the baby boomers who now make up the industry's only stalwart supporters – small operations with tiny lodges resembling locker rooms, where skiers brown-bagged lunches at cafeteria-style tables.

In the 21st century, though, the destination resort has come to define the modern ski experience. But when a weeklong vacation for a family of five during peak season at Sun Valley or Aspen or Whistler can cost as much as a new car, the question the industry must answer is this: Once mom and dad (or grandma and grandpa) stop picking up the tab, will young skiers still ski?

The irony, of course, is that ski technology and resort amenities are better than ever. Hugh Smythe, president of industry giant Intrawest's resort operations (Intrawest owns seven resorts in the U.S. and Canada, including Whistler Blackcomb, Steamboat, and Stratton) from 1989 until 2009, doesn't share this gloomy view. He thinks the industry can innovate its way back to growth.

"From warmer clothing to skis that make it easier to carve a turn and ski through powder to advanced grooming equipment for smoother slopes," he says, "all this stuff is letting a whole group of people ski much later in their lives, and that's great news." Smythe does acknowledge that the industry is facing "a number of economic and climate-change challenges," but says that "so far, technology has been able to keep pace with them."

"Technology," in this case, is a code word for "snowmaking," which was invented in 1950 but not widely used commercially until the 1970s. Today's snowmaking machines combine compressed air with water to make droplets in a complex process that's become essential to most resorts' survival. Almost any mountain company's five-year plan includes upgrading their existing snowmaking, adding more, or both – a business that generates around $1 billion annually. (Along with apparel and accessories sales, it's one of the industry's only robust sectors.)

Snowmaking-machine manufacturers, for their part, are concentrating their energies on delivering fake snow to their ever-increasing customer base using less energy. From fan-powered guns that don't require compressed air to snow-gun towers that allow more time for the man-made snow to congeal in the cold air, the quest to manufacture a better ski slope is itself big business.

Environmental advocates, unsurprisingly, have different, even contradictory feelings about snowmaking. "It's critical for ski-resort operation because you need it to open, and to fill in gaps," Schendler says. "Take away snowmaking, and East Coast resorts are out of business. That said, snowmaking uses tons of energy and cannibalizes the climate on which the industry depends. We're eating our tail to stay alive."

Targhee's Geordie Gillett agrees. "We can't sit around and hope that some piece of technology will appear and miraculously save our snow," he says. In the past two years, Gillett helped make Targhee the first business in the U.S. to register and third-party-verify its greenhouse-gas inventory with The Climate Registry, a nonprofit environmental organization seeking to gather and standardize emissions-reporting figures. "It's a start," Gillett says. "Now we know where we stand and where we need to go." Today more and more resorts are boasting similar greenhouse-gas disclosures, along with varying degrees of commitment to change their energy consumption and buy or produce carbon offsets with wind power. While carbon credits are all well and good, though, the possibility of their changing the trend on warming is more wishful thinking than useful action.

European resorts, many of which lie below 5,000 feet, have already started planning for a snowless future. Spas, shopping centers, restaurants, and a host of other off-piste amenities are being beefed up with euros that a decade ago would have gone toward improving lifts or adding terrain. American resorts, meanwhile, have been bumping up investments in both off-snow and off-season activities. In the '90s, Intrawest revolutionized the industry by adding the now ubiquitous "base village" – essentially, a shopping mall packed with condos – at the bottom of ski hills. Today's summertime activities, which used to center around hiking, have long since graduated to lift-accessed mountain-bike trail riding and are still evolving: In Oregon, Mount Hood Skibowl runs an amusement park at its base, complete with a plastic bobsled track for wheeled sleds, a bungee-jumping tower, go-carts, a zip line, and a rock wall.

Not everybody's in retooling mode, however. Henry Purcell, the owner of Portillo Ski Resort in the Andes Mountains, outside of Santiago, Chile, is doing what he's always been doing. "We've actually seen snow levels increase over the past few years," he says – thanks to a warmer Antarctic ocean producing more frequent and intense storms, which feed Chilean winters – "and skiing in general is growing steadily in Chile with the rising middle class." With a season that runs opposite that of the Northern Hemisphere and a limited number of rooms on-site, Portillo, sitting at almost 11,000 feet, might be positioned perfectly for the future. Of course, even Portillo has seen the glaciers underneath all that powder contract.

While skiing will not disappear in our lifetime, there's no arguing that the window is closing. And while the Hugh Smythes among us are seizing the moment – "I'm having more fun skiing now than I was 30 years ago," Smythe says – the Geordie Gilletts advocate a strenuous activism if we are to have any hope of preserving the sport. "We need to change the way we think, how we live," he says. Effecting real, positive climate change, though – like turning around a stagnant economy – is about as easy as moving mountains.