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  • Hey, good news! I live, right down the road from one of the largest volcanoes in the Earth's history.

  • So here in Montana, it's beautiful,

  • we have a tone of breweries, and chai shops and lovely parks to take my dog to,

  • which is why I sort of have a hard time imagining it being completely destroyed

  • and covered in 6ft burning hot ash and pumice.

  • But, you know me, I live for danger.

  • The fact is, just 250 miles from me lies one of the Earth's largest volcanoes,

  • which you probably know as Yellowstone National Park.

  • And it is still active, though it's not one of those cool, mountainous, oozy volcanoes that Hawaii gets.

  • The Yellowstone volcano is one of a half-dozen or so tantruming mountains that earn the title supervolcano,

  • because its eruptions can eject nearly 250 cubic miles of ash, dust and gas.

  • For comparison, that's about a thousand times the volume of Mount St. Helens' eruption in 1980,

  • which was in itself a pretty big deal. But you shouldn't be surprised,

  • the Yellowstone is famous for its hydrothermal features, like geysers and hot pots and fumaroles,

  • which are all products of this volcanic hot spot, where half-melted magma swirls up close to the Earth's crust.

  • But the problem is, when Yellowstone goes all Christian Bale on us:

  • "Oh, good for you, yeah, you see, you're walking around, duh-tara-tahrah,

  • going through your fumaroles, yeah, I'm gonna kick your #[email protected]&%*!

  • Which it has done three times in its history.

  • Those eruptions were so huge that you can actually still see their effects from space.

  • This ring that surrounds Yellowstone National Park is a crater, or caldera

  • that was caused by a series of eruptions that happened 2.1 million years ago and we can still see them.

  • The first of them was the largest, which left a divot in the ground the size of Rhode Island

  • and deposited ash so far away that the rock formed from that ash,

  • called tuff, can still be found from Los Angeles to St. Louis.

  • The second happened about 1.3 million years ago, was the smallest of the three,

  • still managed to leave a 23-mile-wide crater in eastern Idaho.

  • And the most recent, about 640 thousand years ago, was less than half as big as the first,

  • but still equal to about 2500 Mt. St. Helens', covering hundreds of miles of western north america in a foot of ash.

  • Now, to give you a sense of how mind-blowingly huge these events were,

  • here is how the Yellowstone's greatest hits compare to some other gigantic eruptions.

  • I can't believe I live in the same area code as that thing.

  • Now, there were no people around when the Yellowstone last erupted,

  • but history has shown us what some of its colleagues have done, and it's not pretty.

  • The most recent supervolcano eruption happened about 75 thousand years ago

  • when mount Toba blew its lid in what is now Indonesia.

  • Toba spewed probably around 720 cubic miles of stuff into the atmosphere,

  • sent sulfuric acid rain falling as far as Greenland, and six inches of ash fell in India.

  • And scientists think that all of this debris spewed in the upper atmosphere

  • actually caused a miniature ice age which we can see in the geological record.

  • Ice core samples show that the Toba eruption

  • was followed by a global decrease in temperature of five to nine degrees that lasted hundreds of years.

  • Or maybe that was just a coincidence? We can hope?!

  • So, I know you're wondering whether or not you should cancel your plans to come visit Montana,

  • ehh, first of all, no, you can totally crash on my couch.

  • Secondly, the geologists at the Yellowstone volcano observatory, which is a thing that I'm glad we have,

  • say that if they could predict the eruption of this massive supervolcano, which they can't,

  • it wouldn't be overdue for another 100 thousand years or so.

  • So, there is that, at least, and I hope that you come and visit Yellowstone soon, because it's pretty freaking cool place.

  • Ahh, even if it is one day going to kill us all.

  • Thank you as always for watching.

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  • Because, we're making you smarter.

Hey, good news! I live, right down the road from one of the largest volcanoes in the Earth's history.


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B1 中級 美國腔

黄石超级火山(Yellowstone Super Volcano)

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    joey joey 發佈於 2021 年 05 月 19 日