Global warming is shrinking glaciers all over the world, but the seven tongues of ice creeping down Mount Shasta's flanks are a rare exception: They are the only long-established glaciers in the continental U.S. that are growing.
Reaching more than 14,000 feet above sea level, Mount Shasta is one of the state's tallest peaks, dominating the landscape of high plains and conifer forests in far Northern California. Nearby Indian tribes referred to its glaciers as the footsteps made by the creator when he descended to Earth. Hikers flock to Shasta's peak every summer to scale them.
With glaciers retreating in the Sierra Nevada, the Rocky Mountains and elsewhere in the Cascades, Mount Shasta – the southernmost volcano in the Cascade range – is actually benefiting from changing weather patterns over the Pacific Ocean.
“When people look at glaciers around the world, the majority of them are shrinking,” said Slawek Tulaczyk, an assistant professor of earth sciences at the University of California, Santa Cruz, who led a team studying Shasta's glaciers. “These glaciers seem to be benefiting from the warming ocean.”
Climate change has cut the number of glaciers at Montana's Glacier National Park from 150 to 26 since 1850, and some scientists project there will be none left within a generation. Lonnie Thompson, a glacier expert at Ohio State University, has projected the storied snows at Africa's Mount Kilimanjaro might disappear by 2015.
But for Shasta, scientists say a warming Pacific Ocean means more moist air. On the mountain, precipitation falls as snow, adding to the glaciers, scientists say.