Mount Shasta, Calif. —- Global warming is shrinking glaciers all over the world, but the seven tongues of ice creeping down Mount Shasta 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.

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.

But glaciologists warn that for Shasta's glaciers to even remain their current size, the mountain would have to receive 20 percent more snowfall for every 1.8-degree Fahrenheit increase in temperature.

And global forecasts show temperatures warming from 2 degrees to 11.5 degrees Fahrenheit by the end of the century if no major efforts are undertaken to reduce greenhouse gas emissions.

And another threat to Shasta's glaciers could come far more quickly: a volcanic eruption could melt them, creating mud flows that could bury the surrounding small communities.

Over the last 4,000 years, Mount Shasta has erupted about every 250 to 300 years, and did so most recently about 200 years ago, said William Hirt, a geology instructor at the College of the Siskiyous.