IT WAS 1999 AND WE WERE MOTORING UP A ROCK-LITTERED road high in the Bolivian Andes that was clearly not wide enough for our battered Land Cruiser. Our tires sent stones caroming down the mountainside. As we neared a 180-degree turn, I realized the switchback was built atop a loose pile of rocks. A sideways glance revealed the driver's lack of concern. I studied the latch on my door and mentally practiced flinging it open. It was a hell of a road to climb for a little skiing, but that's what it took to find some decent snow 16 degrees south of the equator.

For 60 years, that road had delivered the ardent skiers of La Paz, Bolivia, to the foot of the Chacaltaya Glacier, where a rudimentary lift yanked them up the world's highest-elevation ski area. When we finally reached the simple, stone-and-timber lodge at the area's base, I grabbed a pair of 25-year-old skis from beneath old posters of the Bolivian Olympic ski team. Then I proceeded to gasp for air while hiking a scree-covered ridge toward the summit of 17,785-foot Mt. Chacaltaya. The lift only operated on weekends, and it was a Wednesday. But no matter—I was thrilled to have a spectacular mountainside and a glacier to ski.

The man who built the Chacaltaya ski area in 1939, Raul Posnansky, was fueled by the same passion. Everyone said skiing at this elevation was impossible, but the Swiss-trained engineer was determined to bring the sport he loved to his home country. So he and his friends hacked a road into the mountain by hand and built a lift on the glacier. Posnansky proved the naysayers wrong. You could ski at 17,000 feet.

Not that it was easy. At the summit, I steadied my breath and dropped over the edge, cautiously skittering along the glacier's steep ice. Then I hit a pocket of powder and everything changed. My adrenal floodgates opened, my insides lightened, and I ecstatically linked a series of arcs down the mountain's face, letting out a loud "Woohoo!" into the thin Andean air. Stopping to catch my breath, I imagined how magnificent the skiing could be with the mountain covered in fresh snow. 

WHICH IS ALL I'LL EVER BE ABLE TO DO NOW: IMAGINE. After years of ever-warming temperatures, Chacaltaya's glacier finally melted completely in 2009. The Olympic ski team and the weekend visits by local families are over. The ski area once known as the world's highest is finished, and skiing in Bolivia is no more. 

From Alaska's Chugach Mountains to the Alps, the high peaks of the world are seeing less snow, shorter winters, and more variable weather, like January rains. The average snowpack in the Pacific Northwest's Cascade Range is 25 percent less than it was 60 years ago. Last winter the Sierra Nevada, home to celebrated ski areas like Mammoth Mountain and former Olympics host Squaw Valley, received just 5 percent of its average snowpack, the lowest in recorded history. In Colorado, Vail and Breckenridge are seeding clouds with silver iodide to wring out extra snow. Eighty-eight percent of U.S. ski resorts now rely on water- and energy-intensive artificial snowmaking to keep their slopes open. According to one recent study, in 30 years half of the ski resorts in the Northeast will be closed due to warm winters. By the end of the century, scientists predict, the resort center of Park City, Utah, will have lost its entire snowpack. At Aspen Mountain, Colorado, snow will only fall on the top quarter of the ski area.

Auden Schendler, the vice president of sustainability for Aspen Skiing Company and a spirited voice on climate change, avoids the chirpy optimism his resort's marketing staff might prefer. "From the climate science I'm looking at, the ski industry doesn't have a real vibrant future," he says.

For years, ski resort operators, like much of society, seemed content to stick their heads in the artificial snow and pretend that climate change wasn't happening. Corporate consolidation was the dominant theme, as larger ski areas focused on expansion and real estate development. Meanwhile, many smaller, local ski hills struggled to keep the lifts running, often due to declining revenue caused by weather shifts.

It took the most unlikely of activists to get the industry to pay attention to climate change. Jeremy Jones was just a scruffy snowboarder living in a tent in Alaska when he filmed his first snowboarding movie in 1995. By 2005, he was a star, one of the world's most well known snowboarders; he's appeared in dozens of movies and been voted Snowboarder magazine's Big Mountain Snowboarder of the Year 11 times. 

Already troubled by the shrinking glaciers he was seeing in the Alps and the increasing lack of low-elevation snow in his favorite Alaskan stomping grounds, that year Jones hiked the unseasonably grassy slopes of a defunct ski area outside Prince Rupert, British Columbia.

"I was with a bunch of guys in their early 30s," Jones explains. "They were so proud, showing me where they learned to ski. I asked why it was closed and was shocked when they said it just doesn't get enough snowfall anymore."

Jones began looking for a climate group to donate to, one that could rally the winter-sports community and one in which "every dollar went into fighting climate change." But none seemed to be speaking to Jeremy Jones the snowboarder. None even mentioned skiing or snowboarding. So in 2007 he founded his own: Protect Our Winters (POW). Thirty minutes after the website launched, donations started coming in.

"People were like, 'Oh my god, thank you. I love skiing and want it to be around for my kids,'" says Chris Steinkamp, a lifelong skier and former advertising executive for car companies who has been POW's executive director since its inception. "We get that all the time. It's an emotional connection for people."

POW has gone on to recruit more than 100,000 young skiers and snowboarders to the cause, garnered global media coverage, and become one of the White House's allies in building support for action on climate change. Could a dirtbag snowboarder and his pals be the activists the climate movement has been waiting for?

Snowboarder Jeremy Jones in Nepal's Khumbu Valley, one day after a first descent from 21,000 feet. | Photo by Andrew Miller

The template for POW's success was set from the start. The tone was inclusive. The aesthetic was hip. The website looked like any rad snowboarding site, with pictures of young athletes hurling themselves down giant mountains. But a closer look revealed advice about push lawn mowers and climate legislation. Readers were encouraged to bike or walk instead of drive, because "stronger legs = better snowboarding." And Jones, the handsome movie star every young snowboarder wanted to be, walked the walk. Literally. He gave up using helicopters for his films, becoming the first snow-sport film star to hike every mountain he rode. In 2008, POW created its first film, My Own Two Feet, about lift-free snowboarding in the Sierra Nevada backcountry. 

The more Jones and Steinkamp learned about being activists those first few years, the more they realized there was one place they needed to go: Washington, D.C. Jones put on a suit (and found someone to tie his tie), and he, Steinkamp, and three others went to Capitol Hill. As you might expect for a group of five skiers and snowboarders with no lobbying experience, things started a bit rough.

"There were a lot of awkward silences," Steinkamp admits about their first meetings with senators. "We didn't have much to say beyond Jeremy telling stories and citing some climate science. You always want to say, 'We're here because we need you to do this.' But we didn't have that part figured out. It was painful."

The experience was not a waste, however. "It captured the attention of a lot of lawmakers, because they'd never really heard firsthand accounts of what athletes in the mountains were seeing," says Steinkamp. "This was in 2010, when today's extreme weather wasn't happening as much yet. But a lot of the senators said, 'Look, until you come back to me with jobs numbers, there's not much I can do for you.'"

So in 2012, POW partnered with the Natural Resources Defense Council (NRDC) to commission a report called Climate Impacts on the Winter Tourism Economy in the United States. It showed that from 2000 to 2010, the $12.2 billion annual winter-tourism industry, which supports 211,900 jobs in three-quarters of the states, lost $1.07 billion in potential revenue to low snow years. The media—from the New York Times to USA Today to over 250 media outlets across the globe—ate it up.

When POW returned to Capitol Hill that fall, it was a whole new game. They weren't just ski stars talking about how much they loved winter. "Now we could say, 'Hey, this is a business issue. This is about your economies,'" says Aspen's Schendler, who joined the POW board of directors in 2010.

"One politician had no idea that his state had the second-most ski resorts in the country," Steinkamp says. "Or how many of those resorts are threatened with going out of business." They also discovered that senators liked meeting with them, because many were skiers themselves. Steinkamp ticks them off: Patrick Leahy, Bernie Sanders, Max Baucus, Tom Udall, Dianne Feinstein. "Even Cory Gardner, a Tea Party guy from Colorado, is a skier," he says. "A nice guy, but we didn't get very far with him."

POW's unlikely activists have a way of cutting through the politics. In 2012, a brief meeting with Alaska senator Lisa Murkowski, known for her commitment to her state's fossil fuels, turned into an hour-long session when she revealed her own love of skiing and listened to the athletes' stories of Alaska. "We had a really good conversation about skiing, and she revealed that her nephew is a ski filmmaker for Sweetgrass Productions," Steinkamp says.

"It's about reach," says Antonia Herzog, the deputy director of NRDC's Climate and Clean Air program. "I don't know how many Twitter followers someone like [Olympic snowboarder] Gretchen Bleiler has, but she can go in there and say, 'I have a huge social media reach, and I care about this issue.' People in Congress care about public opinion, and these are the people a section of the public listens to." (Bleiler has 134,000 Twitter followers.)

But the ski industry pushed back. The executive director of the Maine Ski Association called POW's 2012 report politically biased. Vail Resorts responded with an ad in the New York Times that read, "The Climate HAS CHANGED" above images of skiers frolicking in deep snow. Its CEO, Rob Katz, wrote an op-ed in the Denver Post decrying those who "alarm people with images of melting snow."

The POW team tries to stay diplomatic. "The ski industry is a hard business," Schendler explains. "If you're in California, you've had four years of drought. You won't say, 'Hey, we've got a problem on climate,' because you don't want to reinforce the message that your business is threatened."

Professional half-pipe snowboarder Gretchen Bleiler talks up sustainability at Colorado's Aspen High School. | Photo courtesy of Protect Our Winters/Jeremy Swanson

THE LOW-ELEVATION, BEGINNER-FRIENDLY SKI AREA just outside my hometown of Missoula, Montana, closed in 2003, so my two boys learned to ski on the steeper runs at nearby Snowbowl. We have a family rule: no school on big snow days. Instead, we go to the mountains. I like to think it's my way of teaching them life's priorities. Last winter, we waited and waited, but the powder days never came. It was terribly disappointing for the boys, and it's bound to happen again.

Big deal, you might say. So people don't ski—we've got bigger things to worry about. But losing skiing means generations of kids further removed from the joys of nature in winter. Skiing and snowboarding elicit an almost religious passion from their devotees—people like Posnansky, Jones, and POW's supporters. People fight to save what they love. What happens if there's no snow to love?

As we're learning, snow, with its gradual spring and summer melt, is critical to streamflows, agriculture, and drinking-water supplies. As much as 75 percent of the western states' water supplies are derived from snowmelt. As less snow falls in the mountains of North America, it will affect the ecology and water supplies of the entire continent. The problem is that the effects of climate change, many of which happen gradually over time, are not readily grasped by the public. The potential loss of skiing makes us care. "You might not understand parts per million of CO," Schendler says. "But you can understand snow disappearing."

Upcoming generations are getting a raw deal, so POW makes it a priority to talk to kids. Its Hot Planet/Cool Athletes campaign sends professional skiers and snowboarders into schools armed with ski movies and scientists who talk to kids about climate change. To date, they've presented at 72 schools and reached more than 30,000 students.

"The most optimistic part of what we do is talking to kids about climate change," Jones says. "They're like, 'We want the same world you grew up in. Why is this even up for discussion?'"

POW uses a similar strategy with adults, except with beer. The organization hosts events in ski towns and at ski-movie showings that feel more like parties, where people can mingle with star athletes. And then, in a move Schendler only half jokingly calls a bait and switch, a climatologist comes in to educate the crowd. Schendler admits, "We're trying to use the sexiness of snow sports to suck people into the movement."

The organization recruits professionals into what it calls the Riders Alliance, POW's coterie of high-profile athletes willing to take a public stand. Initially it was just Jones, but as word got out, others soon joined, like Gretchen Bleiler and extreme skier Chris Davenport, both now on the organization's board of directors. Jamie Anderson, an Olympic gold medalist snowboarder and a Riders Alliance member, appeared as a contestant on Donald Trump's Celebrity Apprentice in 2015, raising funds for POW in the process. "We can't wait for others to solve this thing," pro snowboarder and alliance member Julian Carr wrote in an impassioned editorial in the Salt Lake Tribune in August. "We, the younger generation, need to push our elected leaders."

"These young snowboarders and skiers really care about the environment," Steinkamp says. "We just have to make sure we present POW to them in a way that they can really digest, and make them feel part of it."

POW has its eye on bigger, systemic changes that address climate issues, which is why it's not asking recreational skiers or pro athletes to give up their winter passion. "We have got to start transitioning off of fossil fuel, and it's got to start happening yesterday," Steinkamp says. "Skiing doesn't have to be sacrificed. Figure out a way to dial it up in other areas and pull the levers that will make the biggest difference." 

"The reality is that American society is hugely carbon-intensive, and you can't pick and choose what industry can speak on these issues and what business can't," says Schendler. "So the idea is to use our business to help fix the whole system so that people can ski with low carbon footprints, so they can travel with low carbon footprints. Let's use the ski industry for good."

POW's ability to reach young people is why Jones was invited to the White House in 2013 to accept a Champions of Change award. While there, he presented a letter signed by 75 professional skiers and snowboarders asking President Barack Obama to take meaningful action on climate change. Later that year, the White House asked POW for help promoting its Clean Power Plan, aimed at regulating power plant emissions. POW got all of its athletes to take photos from the mountains to show what was at stake and post them with the hashtag #actonclimate. In its first week, the hashtag was seen 10 million times.

The EPA was so pleased with the burgeoning partnership that the agency sent its administrator, Gina McCarthy, to appear with POW at the Aspen X Games in January 2015. When the president unveiled the Clean Power Plan last August, Steinkamp was in the room. 

The ski resort industry is starting to take climate change seriously, too. Besides Aspen's industry-leading efficiency initiatives, Alta in Utah recently installed solar panels, Jiminy Peak in Massachusetts installed a wind turbine, and Mt. Abram in Maine is now primarily solar powered. "These resorts are doing really admirable work greening themselves," Schendler says. 

In September, POW recruited the industry's two central associations, the National Ski Areas Association and Snowsports Industries America, along with 53 resorts in 15 states, to sign a letter urging the White House to take strong action at the recent United Nations Climate Change Conference in Paris. Partnering with Ski Utah, a trade group for the $1.2 billion winter-tourism industry in one of the country's reddest states, POW helped persuade Utah's coal-friendly governor, Gary Herbert, to support the Clean Power Plan.

Looking ahead, Protect Our Winters will send athletes to speak at colleges across the country in a get-out-the-vote campaign for the 2016 election. It's also eager to engage people involved in non-winter outdoor activities. "Maybe you're not a skier, but you're a trail runner or a mountain biker or a climber. That's tens of millions of environmentalists right there," Schendler says. "They are fanatics of the outdoors. That's a movement. Of 300 million Americans, you don't need 300 million to care about climate. You need 20 million."

It's inspiring talk, and these guys know that if they can't pull it off, if we can't get climate change under control, two terrible things will happen: Skiing as we know it will cease to exist, and skiing will be the least of our worries. "This is a double-black-diamond moment," Schendler says. "This is the place where we cannot fall."

See the POW athletes in action:

This article was funded by the Sierra Club's Climate Recovery Partnership and appeared as "Empowdered" in the January/February 2016 print edition of Sierra.

For Sierra Club ski, snowshoe, and dogsled trips this winter, go to sc.org/snowtrips.