Every March, teams of sled dogs and their drivers, called mushers, trek across the Alaskan wilderness during the Iditarod Trail Sled Dog Race. But as the start of last year’s race approached, there wasn’t enough snow at the starting point.

Organizers had to bring in 15 truckloads of snow from other parts of Alaska to cover the track. A few years earlier, the starting point was moved due to lack of snow. Some scientists blame the shortages on warming temperatures due to climate change—and they suspect the problem may become more common.

How will that affect the historic race? “I see a future in which the race will be modified,” says John Walsh, a climate scientist at the University of Alaska. This might mean moving the path farther north or starting earlier in the winter.