I used to think that the explosion of Krakatoa in 1883 was THE BIG ONE, but not compared to the time in 1815 when Mt. Tambora on Sumbawa Island (in today’s Indonesia) detonated.
There had been nothing on this scale since the Lake Taupo eruption in New Zealand 1700 years earlier.
So much ash was jettisoned into the sky that 1816 was known as the “Year Without a Summer”. Crops failed all over the world. There had been several other volcanic eruptions in the previous years so this era became known as the Little Ice Age. No other seven-year period had been this active since the Stone Age.
Volcanoes can punch your ticket in a variety of interesting ways. Of course, there is the familiar cascade of lava routine. This is generally pretty slow-moving, and though your garden gnomes and lawn furniture may go poof!, you can step out of its way. Oh, unless it happens to blast the molten rock skyward and comes raining down with the wrath of an angry Norse god. When you see this stuff coming, you’ll be glad you bought the extra rental car insurance.
Then there is the hot ash situation—which generally gives you time to make a run for it. But if you linger until the very last minute waiting for your pizza, you can end up as a plaster cast in a museum like some folks in Pompey. “Oh hell, I better take that to go!”
There are all sorts of ways to die when the earth decides to rock and roll. In 1902 on the island of Martinique in the Caribbean, Mt. Peleé blew and took a city of over 30,000 with in less than a minute. Superheated poison gas surged down the mountain, and if you were in its way you were instantly cremated. Only two people survived.
If you are lucky all you get is a rain of pumice, which can be almost fun if you are far enough away. This is where the ejecta mixes with water, forming air pockets and creating a material so lightweight that it floats on the sea. Quickly shut down your ship’s engines as this will gum up the cooling system but good.
Of course there is often persistent smoke, which is like any carbon-laden exhaust, so if you are downwind it’s Joe Camel time—times 100.
One of the more common ways to die from a volcano is to climb it and fall in. This happens all the time. Someone studied data from the last 600 years and determined that an average 540 die from volcanos each year, though I don’t know if this includes falling in.
With all sorts of natural and manmade disasters on offer, extreme volcanic events don’t keep most folks up at night. Lots of people are worried about an asteroid strike or terrified of the effects of global warming. Nuclear war, sure. Even the return of bell bottom pants would be horrible, but let’s add to the list what happened 640,000 years ago in Yellowstone. This was a supervolcano which blasted as much as 300 cubic miles of sticks and stones into the sky. And if it were to happen again in a similar fashion, it would make Mt Tambora’s 10 cubic miles look like a BB-Q fire—and roasted garden gnomes would be the least of your worries.
Did you ever wonder why the magma bursts forth from the depths of the Earth? It works like this: We live on relatively thin crust (about as thick as the skin of an apple) which is 3-5 miles thick under the oceans and about 25 miles thick under the continents. The tectonic plates float on this molten rock, which is in constant flux due to the top-to-bottom temperature differential (as opposed to pressure). If this mantle was under intense pressure, a hole in the crust would cause the Earth to turn inside out—making any other problems you have seem irrelevant (hey, take the win). At 1,800 miles deep in one gets to the heavy metals, and at the center the pressure is 45,000,000 psi. Or roughly equivalent to 10,000 elephants standing on a postage stamp…roughly.
But why after 4.543-some years is the earth’s core still hot? In fact, it is about 10 million degrees F, which is hotter than the surface of the Sun. I was taught in school (I think Eisenhower [we called him Ike] was president) that Earth’s core has always been hot and just never got around to cooling off. This is only partly true. As you know, the Earth gives off about 44 trillion watts a day and about 15 trillion of these is the leftover heat from the Garden of Eden days. The rest of the heat is from radioactive decay of uranium and thorium combined with that generated by tidal forces from the pull of the moon. Neat system, but you can bet we’ll screw it up.
In the end, volcanoes remain (in most of the world) an unlikely disaster scenario. But stuff happens, like the time one of my kids tripped at the edge of Mt. Vesuvius and nearly fell in. It would have made a great story, but still…