Ah, volcanoes: A cross between nature's spots and Mother Nature on her period. I said in the last post that I would cover volcanoes separately. This is purely because I've got a fair bit to say, and I will no doubt erupt into a particularly fiery rant, but there it is.
The most famous volcanoes all have the same thing in common: Mount St. Helens, Krakatoa, Vesuvius, Mount Tambora.
They were all very, VERY explosive eruptions. Krakatoa wiped itself off the face of the earth with the loudest noise ever heard. The Australians could hear it - from 2,000 miles away.
Mount St. Helens tore itself open in May 1980, killing 57 people and leaving the famous horse-shoe crater it has today.
Vesuvius, as we all know, left Pompeii, Herculaneum, and its peoples buried under ash for centuries.
Mount Tambora, erupting in April 1815, caused enough climactic abnormalities for 1816 to be dubbed the Year Without a Summer.
And yet, these are nothing to the havoc a super-volcano can cause. Far from creating a single year's worth of trouble, super-volcanoes can cause the Decade without a Summer. That's a volcanic winter ten years long!
But what are they exactly? Giant volcanoes, yes, but what makes them different? The technical definition is that a super volcano is any volcano capable of throwing out 1,000 cubic kilometres (240 cubic miles) of stuff in one sitting.
But there aren't just the massive calderas, like Yellowstone. There are also large igneous provinces, such as the Deccan Traps in India, and the Siberian Traps in the north. These are giant areas of basalt rock, laid down usually over millions of years from almost never-ending flood basalt eruptions (basalt is a type of volcanic rock).
But for the sakes of this post, I'll keep to the calderas we're all worried about. And here is where I'll get a bit ranty.
By far the best known super-volcano caldera lies under Yellowstone National Park; although mostly contained in Wyoming, it also stretches into Montana and Idaho. But that is just the park itself - the caldera is 50 miles long and 12 miles wide, or 80 km long and 20 km wide, according to research from 2013.
By the same research, this caldera has the potential to hold 4,000 cubic kilometres/ 940 cubic miles of "melt", although in 2013, this was only between 6 and 8% filled with molten rock. Despite believing that this amount of melt isn't enough to cause a super eruption, the caldera is still 2.5 times larger than scientists had originally believed.
BUT, Yellowstone is NOT the only super-volcano in the entire world. America isn't the only country with a fiery threat of doom grumbling beneath its feet.
There are a grand total of 6 super-volcanoes that are considered dormant or active in the world today, of which Yellowstone is only one. While America can't claim the privilege of having the one and only super-volcano, it DOES have the dubious honour of holding half of the world's super-volcanoes, being also home to the Long Valley caldera in east-central California (because being God's Etch-a-Sketch with the San Andreas just isn't enough) and the Valles caldera in New Mexico.
Elsewhere in the world, there is Lake Toba in Northern Sumatra, the Aira Caldera in Japan, and the Taupo caldera threatens all hobbits in New Zealand.
Of all of these, Aira has exploded most recently, at only 22,000 years ago. And to be fair, Yellowstone is considered to be one of the most dangerous of all super-volcanoes today, purely because it tends to have a cycle of a super-eruption every 600,000 to 800,000 years.
I'm sorry, but to say that just because it's been 640,000 years since the last eruption that Yellowstone is "overdue" is just ridiculous. Plus, super-volcanoes can give off "baby" eruptions. The last lava flow at Yellowstone was only 70,000 years ago! So I'd be more concerned for North America in about 170,000 years.
However, there is a super-volcano that dwarfs even Yellowstone. Lake Toba is the only super-volcano on earth that can not only be described as Yellowstone's big sister, but can also be seen from space.
When it last erupted 74,000 years ago, it ejected 2,800 cubic kilometres of detritus, and is thought to have killed off between 50 and 60% of the human population at the time (although the scientists are still arguing about this today).
To be honest, I'm not entirely worried about Lake Toba, Taupo, or the Aira Caldera. All have erupted within the last 100,000 years, and it takes at least that long for a super-volcano to get its spark back. Taupo last went off 26,500 years ago, and Aira went off much closer to today than that - so these two and Lake Toba are more likely to be sleeping for a few thousand years yet.
Yes Yellowstone is a potential threat today, but just because its alarm usually goes off around this time, it doesn't mean that Yellowstone is such a light sleeper.
Of more concern are Long Valley and the Valles calderas - Long Valley especially. Despite erupting 760,000 years ago, it gave off a swarm of strong earthquakes in the 1980s, as well as lifting 100 square miles of the caldera floor 10 inches. Then, in the 1990s, large amounts of carbon dioxide from magma below the surface began killing off trees in the Mammoth Mountain side of the caldera.
Scientists believe that this means that an eruption of some sort is years away at the very least, but more likely decades or even centuries. Valles Caldera is just as active today as well, heating thermal springs.
But both are still quite small for super-volcanoes. In their last eruptions, both threw out around 600 cubic km of ejecta - just below the 1,000 classification for a super-volcano, but still big enough to cause immediate difficulties for America, and climactic difficulties worldwide.
So as far as our apocalypse is concerned, yes super-volcanoes are a possible source for it to come from. But we have survived volcanism for at least 200,000 years, and our ancestors have survived it for the better part of 5 million years. The fact that we're so preoccupied with how humanity will end, it means that we run the risk of not enjoying our existence while we still can.
I mean, the dinosaurs were the top dogs for 160 million years, so there is absolutely no reason to suppose that we can't expect the same sort of winning streak. I suppose it boils down to something Khalil Gibran said:
"If your heart is a volcano, how shall you expect flowers to bloom?"
If we remain so concerned with how our world will end, by fire, by water, by events that are ultimately beyond our control, then we miss the beauty that is around us right now. This is the last depressing post for some time, I promise. Mount Depressive is dormant as of now!
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