PHILADELPHIA (KYW Newsradio) — A volcano recently erupted underwater in Tonga, starting a tsunami that caused incredible damage. The blast was visible from space.
How much damage could a Pompeii-like massive eruption from a supervolcano in the U.S. actually do?
Listen below in your podcast player.
"It would cause severe disruption," warns Dr. Loÿc Vanderkluysen, associate professor of volcanology at Drexel University.
"A typical super-eruption at Yellowstone would probably be able to dump about an inch or two of ash all the way to Philadelphia if it were to erupt again."
Vanderkluysen said there are two volcanoes in the contiguous 48 states that can cause super-eruptions reaching a seven or eight on the Volcanic Explosivity Index (VI), the two highest levels: Yellowstone in Wyoming and the Long Valley Caldera in California.
Neither of these follows the tradition of what we think a volcano typically looks like, such as what you see above in top illustration.
Related
"Generally, people will think of a volcano as some sort of pointy mountain," Vanderkluysen said.
"But there are plenty of volcanoes that really don't fit that definition at all. If you're thinking of Yellowstone, it's actually kind of flat and more like a hole in the ground."
But Vanderkluysen detailed how volcanoes, no matter what the shape, always include magma which is liquid rock that comes to the Earth's surface.
"As long as you are able to form liquid rock somewhere inside the earth, and make it rise through the crust so that it gets to the surface, then you can call it a volcano," he added.
Related
The bad news: Vanderkluysen said both Yellowstone and Long Valley Caldera still have supervolcano capacity.
The good news: They don't happen that often, and that’s a dramatic understatement. There also appears to be a limit to how many times the calderas can fire up one of the deadliest of volcanoes.
"Just because it has eruptions on average every 600,000 years doesn't mean they can't wait a million years," he said.
"If you're talking about my lifetime, your lifetime, your audience's lifetimes, right now, there's no sign that Yellowstone is recharging its reservoir that is getting ready for another super-eruption, like it had three of them."
Vanderkluysen said as well that some of these volcano systems like Yellowstone and Long Valley often have only three or four super-eruptions in them.
Related
"Yellowstone already had three. There's no evidence that is going to actually make a fourth of these extremely large eruptions," he said.
"So at this moment, the supervolcanoes in the U.S. are pretty quiet."
If for some reason one of these super-eruptions happen, he said it won't take out 90% of the world's population.
But it would produce a societally-disruptive nationwide mess across America, as well as a lot of potential death.
Related
"If you dump a foot of volcanic ash over the Midwest, you would probably have problems for the food supply," he said.
"Because this is a large area where we grow a lot of food, it would cause problems for power lines. It would cause problems for delivering truck traffic across large swaths of the United States because ash is not like snow. It doesn't melt. It has to be cleaned up. A lot of the grazing animals would have problems, ash on grazing grounds, can cause health issues...now you're talking about the beef supply, and the food supply, for beef, and all the things that would be severely disrupted.
Vanderkluysen added that the ash in the air would halt all airline traffic over the U.S., as well as create a short circuit in power systems.
However, he said the "kill zone," where 90% of people would die if they don't evacuate, would cover a space in the western U.S. equivalent to that of the state of Idaho.
"Because these larger eruptions tend to also have a lot of warning signs, we would be able to evacuate people or majority of people, but we're talking about massive scale evacuation across the Mountain West region of the U.S.," he said.
Related
"Deer, beavers, raccoons and all the other wildlife that exist there would be wiped out completely."
Anyone within 10 to 20 miles of either caldera could also experience death by "blocks of rocks that are maybe the size of a car," Vanderkluysen added.
"Getting crushed by these rocks that start falling from, you know, two or three miles up in the sky. If you are not paying attention or it's too dark, you're just going to get pelted by rocks the size of a piano."
Vanderkluysen described other ways that people would find their doom between Idaho and the Midwest in the incredibly unlikely event that one of these calderas erupt in our lifetime, and other problems that would affect people here on the East Coast, as well as other reasons why such a cataclysmic event is extremely unlikely.
Listen below in your podcast player.