A very good non tin foil article what it would be like if the Yellowstone Caldera let loose.
What if Yellowstone's supervolcano erupts?
An eruption from Yellowstone could create an ash cloud that would affect the entire world's atmosphere for a decade or more.
By Natalie Wolchover, Life's Little MysteriesMon, Jun 04 2012 at 2:11 PM EST
A scenic, albeit volcano-y, spot in Yellowstone National Park
NOT FOR PICNICS: A scenic, albeit volcano-y, spot in Yellowstone National Park in May 2011. (Photo: ZUMA Press)
A rough estimate based on geologic records indicates there's a 1-in-10,000 chance of a "supereruption" at Yellowstone during our lifetimes. However, given the erratic nature of volcanoes, that number doesn't mean much. The bulging pocket of magma swishing around beneath Old Faithful might never blow its lid again. Or, it might put on a surprise fireworks show next Independence Day. Scientists just don't know.
But if or when it blows, what will actually happen? Will it be the end of us all, or just a big knock to the tourism industry in Wyoming?
Each of the three past supereruptions of the Yellowstone hotspot spewed more than 1,000 cubic kilometers of magma into the environment — the benchmark of a "supervolcano." According to Jacob Lowenstern, scientist-in-charge at the Yellowstone Volcano Observatory, that's a large enough eruption to cover much of North America in an ash blanket of varying thickness.
"The ash is thick (more than about 30 centimeters of ash) near the eruption source and a small fraction of a millimeter once you move 2,000 miles away. It's fair to say that a trace of ash would be found over most of the United States, though it would only be thick enough to collapse roofs in the states closest to Yellowstone," Lowenstern told Life's Little Mysteries.
With enough warning, the states near Yellowstone could be evacuated, which would largely avoid a tremendous loss of life caused by the downpour of ash, the scientists said. But that's just in the short term; the aftermath would be the rub. For several days, ash would hang in the air, making it difficult to breathe. And that blanket of ash covering the country would smother vegetation and pollute the water supply, quickly leading to a nationwide food crisis. "A lot of people would perish," said Stephen Self, director of the Volcano Dynamics Group at the Open University in the U.K. He envisions American refugees lining up at the Mexican border.
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