What would skiers do without snow? Four U.S. Olympic athletes never want to find out, so they’re teaming up with WWF to push for comprehensive clean energy and climate change legislation this year. Bode Miller, Ted Ligety, Hannah Kearney and Julia Mancuso wrote an open letter to the Senate about how climate change could affect the future of their sport and of the planet.

“We can attest to the impact climate change is having on America’s mountains,” the gold medal-winning athletes said. “Firsthand, we are seeing shorter seasons, declining snowpack and earlier snowmelt.”

“According to a major government report released last year, some areas in the Northwest are already seeing a 60 percent decline in snowpack. By the end of the century, the snow season in many areas of the U.S., especially the Northeast, could be cut in half if action isn’t taken to cut global warming pollution.”

This isn’t the first time these Olympic skiers have spoken out on behalf of the environment. Kearney and Mancuso were both featured in an MNN gallery about 12 Olympic athletes who want to save the planet.

“Protecting the Earth is important as a citizen and especially as a winter athlete who competes on a surface created by nature,” said Kearney, a 24-year-old, hybrid-driving freestyle skier.

Mancuso climbed Mount Kilimanjaro in 2008 to raise money for Right to Play, an organization that helps underprivileged kids around the world through sports. She’s a regular collaborator to WWF Climate Change and LIV NGO, which promotes global wellness.

Anyone who wants to join Kearney, Mancuso, Ligety and Miller in protecting nature from dangerous climate change can get more information at WorldWildlife.org.