New scientific evidence shows that the Death Valley volcano last erupted only 800 years ago, not 10,000 years ago as previously thought. Other
evidence shows caldera volcanoes can erupt more frequently than previously thought. Of particular concern are large known historically explosive
calderas around the world that are not monitored.
"There are several large and still active calderas in the United States, including the one under Yellowstone National Park. All are closely
monitored. What worries the researchers are other unmonitored calderas around the world with the potential to send huge clouds of ash into the
atmosphere, causing massive ecological and climate damage."
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