As a new ski season approaches, it's interesting to note that those choosing to ski, snowboard, or recreate in general on California's Mammoth Mountain will be doing so . . . on a supervolcano.

While the supervolcano beneath Yellowstone is known to many, Long Valley may not be. As one of the largest supervolcanoes in the world, the Long Valley Caldera is 20 miles long and 11 miles wide. When it blew up 760,000 years ago, it threw 140 cubic miles of material and gas into the atmosphere.

For a modern perspective, this equals the amount ejected from Mt. St. Helens in 1980 . . . times 500.

Today, according to researchers, the Long Valley supervolcano has re-loaded, with some 240 miles of magma beneath its surface. If this amount erupted, there would be 800 times the material and gas released into the atmosphere as at St. Helens. While there's fortunately no imminent danger of this, an uptick in geologic activity has been detected over the last four decades.

Here's a look at some other massive volcanic eruptions over [geologic] time along with the volume of material/gas affecting the atmosphere.

But located on the western perimeter of this Long Valley Caldera is Mammoth Mountain. Here's a map of it:

Having skied at Mammoth Mountain many times, never realizing the exact geologic nature of the terrain, we had always heard the faint rumblings about the earthly issues surrounding the mountain. But now we fully understand that we've been skiing on a lava dome all these years.

A big part of this volcanic material is CO2 gas.

Mammoth itself is actually "outgassing large amounts of carbon dioxide." In April 2006, three Mammoth Mountain ski patrol lives were lost when they fell into a fumarole on the mountain. As CO2 is heavier than air, they died from suffocation.

So if you find yourself skiing Hangman's Hollow on Mammoth sometime, after you're done cursing the hill, you can also blame the mountain for "climate change."