A new study on climate change provides a bleak outlook for U.S. towns that rely on winter tourism.

Shorter winters equal fewer skiers on the slopes, which equals fewer people patronizing the restaurants, hotels, grocery stores and other businesses that depend on a steady stream of visitors each ski season.

“Climate change is expected to contribute to warmer winters, reduced snowfall and shorter snow seasons,” the national report from the University of New Hampshire states. “This spells economic devastation for a winter sports industry deeply dependent upon predictable, heavy snowfall.”

Environmental groups Protect Our Winters and Natural Resources Defense Council funded the study released this month. The authors, Elizabeth Burakowski and Matthew Magnusson, point to last winter as a prime example of how climate change is hurting winter tourism.

December 2011 to February 2012 was the fourth-warmest winter on record in the United States since 1896, with the third lowest snow cover since 1966, their research shows. According to a survey by the National Ski Areas Association, 50 percent of responding ski resorts opened late and nearly that many closed early.

Whitefish Mountain Resort was one of the resorts to open late last season. Lifts fired up a week after the proposed opening day, and even then terrain was limited with only a 24-inch snowpack at the summit and almost no natural snow in the village area.

Whitefish did finish the 2011-12 season as scheduled with average snow totals — but many other ski areas in the region weren’t as lucky.

Winter temperatures in Montana have increased by about 2 to 4 degrees in the past 40 years, the report notes. By the end of the century, winter temperatures are projected to rise an additional 5 to 7 degrees, and snow depth could decline by 10 to 50 percent in Northwest Montana.

The predications are even more dire in Southwest Montana where the average snow depth could decline by as much as 50 to 100 percent.

Protect Our Winters said the goal of the study is to help policymakers understand both the ski and snowmobile industry’s current economic scale and the potential economic impacts that climate change may cause.

Montana’s winter tourism industry provided more than $152 million in income to more than 4,500 employees during the 2009-10 winter, the report states, while the skiing and snowmobiling industries combined contributed more than $265 million to Montana’s economy.

The economic impact of a below-average snow year is clearly evident in Montana, the report says. Low snow years result in about 4 percent fewer skier visits to Montana, which equates to a loss of about $16.1 million in resort revenue statewide.

Whitefish Mountain Resort employs as many as 500 workers during the winter, while many restaurants, hotels and shops in town rely on visitors lured here by the ski slopes.

Resort spokeswoman Riley Polumbus says resort decision-makers pay attention to reports about climate change and are glad the conversation is happening, but they’re not ready to hit the panic button. In fact, business has been good recently, with 2008 and 2010 rated as two of the best snow years in a decade, and this season is shaping up nicely with sufficient early snow.

However, the lack of snow at lower elevations early last ski season was enough to sway decisions about future investments at the resort.

A project planned to start next year will add a new lift to Flower Point on the north side of Big Mountain where slopes tend to gather more snow at a higher elevation. The Flower Point plan trumped a different plan to move Chair 4 and Chair 5 on the front side where snow can sometimes be thin early in the season.

“Last year we had to delay the opening by a week, and when we did open it was only terrain on the north side,” Polumbus said. “This year, we were better off than last year, but we still had to download on opening day.”

Lost revenue from the delayed opening in 2011 was a catalyst to make the Flower Point project a top priority. Polumbus says the plan to move Chairs 4 and 5 is still on the table.

Polumbus said there have always been ebbs and flows to snowfall totals at Big Mountain. As early as 1947 — the year Big Mountain opened —the season didn’t start until mid-December due to a lack of snow. Other years bring mounds of snow, such as 2008 when a record 426 inches was tallied.

Still, the authors of the climate study conclude from their research that winter as we know it is “on borrowed time.”

“We need to protect one of America’s greatest assets — a stable climate. Without it, a vibrant winter sports industry, the economies of mountain communities everywhere, and the valued lifestyle of winter will be gone, not just for us, but for our children.”

The full study is available online at www.protectourwinters.org.