It's May in Rocky Mountain National Park, but on a mountainside 10,829 feet above sea level, snow is falling. It's pelting Jim Cheatham, a biologist with the National Park Service. Shrugging off the cold, Cheatham seizes a teachable moment. This snow, he says, holds more than just water.
"Chances are it's carrying the excess nitrogen we're talking about," says Cheatham.