Post-Supervolcano-Eruption

Did you mean a volcano in Yellowstone or the Yellowstone Caldera? When the Yellowstone Caldera erupts again, if it does, there probably will be several years without Summers.You could even make that decades without Summers. The exact length can't be predicted, st least not now. It might be possile when it is learned how fast the magma chamber is filling. I believe that it is thought that the Winter from the eruptions that created the Deccan Traps lasted for centuries.

The ash would cover the Great Plains to an unreasonable depth, but that would depend on how long the eruption lasted and the nature of the material that will be ejected. It might become a lave eruption like the Deccan Traps.

The ozone layer would be a minor matter, because there really isn't an "ozone layer" per se. There is an ozone process. ultraviolet radiation of vcertain wavelengths break down diatomic molecules and assist in the creation of triatomic molecules, and ultraviolet radiation of other wavelengths knock one oxxygen atom from a triatomic molecule. The depth of atmosphere is more important, because the ultraviolet is more likely to hit something if there is more air or dust in the way.

One thing to remember is that the atmosphere is largely separated by hemisphere, North and South. The air from the Northern Hemisphere only mixes into the Southern Hemisphere very slowly, so the dust would go South of the Equator very slowly. Consider that it was a couple of years after the explosion of Krakatoa before the Year WIthout a SUmmer in the Northern Hemisphere. If you wish to, then you could kill off all of the people from the North along with as many as you want from the South.

There would be a number of interesting contrary things that would happen to the tmosphere. Much of the solar radiation would be absorbed by the dust, so even though there would be little or no sunlight getting to the surface the air temperatures wouldn't be all that low. And methan and other gasses that are emitted by volcanoes are excellent for the greenhouse effect. The vegetation would die from lack of light, and the animals would die from lack of food and poisoned water and aur, but the temperature would be above freezing most of the time, or that is one theory. Another theory is that the Earth could become an iceball again.

Have a merry time writing this one.

King Neptune said:

There would be a number of interesting contrary things that would happen to the atmosphere. Much of the solar radiation would be absorbed by the dust, so even though there would be little or no sunlight getting to the surface the air temperatures wouldn't be all that low. And methan and other gasses that are emitted by volcanoes are excellent for the greenhouse effect. The vegetation would die from lack of light, and the animals would die from lack of food and poisoned water and aur, but the temperature would be above freezing most of the time, or that is one theory. Another theory is that the Earth could become an iceball again.

Click to expand...

OTOH, there don't seem to have been any massive global catastrophes on that scale the last few times a supervolcano erupted (the most recent was Toba in Indonesia, approx. 70,000 ya). When Yellowstone blows, North America's screwed, but the rest of the world maybe not so much.

The year without a summer was Tambora 1815/16
http://en.wikipedia.org/wiki/Year_Without_a_Summer

The sound that was heard around the world was Krakatoa 1883
http://en.wikipedia.org/wiki/Krakatoa

An interesting set of short stories, about a YS eruption, to read is A Land of Ash by David McAfee and Daniel Arenson edited by David Dalglish

maggi90w1 said:

No? Damn. The story was supposed to take place in Europe.

Click to expand...

Think dark ages coupled with feudalism and you should be fine. It is hypothesized that the dark ages were due not only to influences by the sun but also due to one of the lesser supervolcanoes erupting, either Long Valley or Taupo in size.

maggi90w1 said:

No? Damn. The story was supposed to take place in Europe.

Click to expand...

Do you remember a few years ago when that volcano in Iceland blew, and the floating ash shut down air travel throughout western Europe? I guess flying through the ash is dangerous... changes air patterns around the airplane somehow and makes it crash.

You talked about destroying society - if Yellowstone blows, I would imagine there would easily be enough ash to shut down air travel. That could contribute to isolating Europe from the rest of the world. Then maybe the decreased amount of sunlight combined with ash on the soil makes it difficult/impossible to grow crops. Or the only species that can survive are invasive/not particularly nutritious plants.

Honestly, IMO there is so much we DON'T know about what would happen if Yellowstone or another supervolcano blows, I think you could get away with a lot of potential catastrophic ends.

benbenberi said:

OTOH, there don't seem to have been any massive global catastrophes on that scale the last few times a supervolcano erupted (the most recent was Toba in Indonesia, approx. 70,000 ya). When Yellowstone blows, North America's screwed, but the rest of the world maybe not so much.

Click to expand...

Au contraire. The Toba eruption, dated at about 74,000 years ago, coincides almost exactly with a major constriction in the human DNA genome, as worked out by geneticists. They estimate the entire human population of the planet was reduced to as few as about 3,000 individuals. There are, of course, no written records, or even oral traditions, relevant to that event, and it happened at a time when vast continental glacial sheets covered North America as far south as Illinois, Europe as far south as the Alps. There were no humans in the Americas at this time.

As for the effects of a major Yellowstone event on the scale of the last one, 630,000 years ago, we of course have no historical comparisons. But we do have Tambora, in 1815. Tambora is estimated to have ejected ~160 km3 of ash. The atmospheric aftereffects of that disrupted the weather in North America and Europe the following summer to the point that snow fell in New England in July, crops failed there and in Europe, and thousands of people starved.

It isn't simply a matter of particulate ash. These big eruptions also send vast quantities of sulfur aerosols into the stratosphere, which absorb sunlight and linger there for a long time, longer than the ash does.

Ash tends to be very acidic, the consequence of contained sulfur, mainly. Ash eventually weathers, producing clays and silt; the rate of that depends on climate in any local area, but that happens on a scale of decades or longer, generally.

Yellowstone, 630,000 years ago, ejected more than 10 times what Tambora did. Tambora, the largest historically-recorded eruption, was more than 10 times what Pinatubo did in 1991, and Pinatubo was more than 10 times what St. Helens did in 1980.

Oh, and by the way, the last three big Yellowstone events occurred 2.1 million years ago, 1.35 million years ago, and 630,000 years ago. Make a graph extending to today.

And, just for more paranoid fun: Yellowstone isn't the only active supervolcanic caldera in the U.S. There's also Long Valley, in California, which is of similar scale, and definitely has a filling magma chamber beneath it. It last went off about 750,000 years ago.

caw

A better super volcano to study would be the Long Valley Super Volcano Complex in California, it erupts more frequently than YS does, but with affects almost as devastating as YS, and is less likely to take out the entire northern hemipshere allowing for a small portion of humanity in say europe to survive though it would be rough.

melindamusil said:

Do you remember a few years ago when that volcano in Iceland blew, and the floating ash shut down air travel throughout western Europe? I guess flying through the ash is dangerous... changes air patterns around the airplane somehow and makes it crash.

Click to expand...

No, the ash is sucked into the engines and destroys them. Then you crash.

blacbird said:

Au contraire. The Toba eruption, dated at about 74,000 years ago, coincides almost exactly with a major constriction in the human DNA genome, as worked out by geneticists. They estimate the entire human population of the planet was reduced to as few as about 3,000 individuals.

Click to expand...

There's also evidence against such a constriction in the population, or for a much less drastic one.

Obviously any supervolcano eruption is going to produce Seriously Bad Results for most of the world for at least a few years. Not fun times for anyone. But the timing of known past supervolcano events does not coincide with the timing of other known past global cataclysms (mass extinctions, major glaciations, etc.). For that, you need something on a much larger scale, like the Deccan Traps or the Siberian Traps.

OP: If Yellowstone erupts, you're probably safe positing a "nuclear winter"-style crop failure/famine scenario for Europe for a few years & a prolonged recovery time, but it's not going to wipe out everything & everybody. It's happened before & the world survived pretty well on the macro level. (Individuals, of course, may not find that much consolation.)

benbenberi said:

OTOH, there don't seem to have been any massive global catastrophes on that scale the last few times a supervolcano erupted (the most recent was Toba in Indonesia, approx. 70,000 ya). When Yellowstone blows, North America's screwed, but the rest of the world maybe not so much.

Click to expand...

While the last several explosions of supervolcanoes have not been all that large, there have been some very large ones further back. The type of eruption and how long it will last will determine how much damage would result.

maggi90w1 said:

No? Damn. The story was supposed to take place in Europe.

Click to expand...

Don't let that worry you. A major super-volcano eruption could turn the Earth into a chilly, dark place, and it could kill whatever percent of the human population that you want to get rid of. If you want Europe to be badly harmed, then make the eruption a huge amount of dust.

You could even use Iceland as the source instead of Yellowstone. Remember the problems created by one little volcano a few years ago. Multiply that by a few orders of magnitude and play with the idea. The mid-Atlantic ridge has been continually active for a very long time, and there is no reason why it couldn't increase enough to make Europe uninhabitable.
Then there's the Great Rift Valley, which isn't far to the South and East; there are many volcanoes along it, and a little more spreading could cause many more volcanoes.

There are a few other places where mid-oceans rifts are opening, and any of those could be used, unless you are writing non-fiction.

Possible scenario's of a YS Caldera eruption...

1...1/3 of the western united states would be wiped out. Any Nuclear plants or missle silo's in the area could also go nuclear causing further destruction. You would also have to factor in such things as would a YS eruption, cause earthquakes or other volcano's in the area to erupt as well. And there are several large Caldera's in the area...

2...Ash drifts eastward, thus shutting down large sections of travel by air, barge, train, and highways. This would cause a major problems on shipping vital supplies, like fuel, food, medicine. Panic spreads as crop failures happen on wide scales and prices go up...

3...Russia, China or another lesser power sees a chance to strike at the US while we are preoccupied, thus Global Nuclear War.

4...Nuclear Winter, thus reversing global warming and we get a minni ice age. Lots of plants and animals die, not to mention humans. All would migrate south and reverse immigration in South America and Central America would change the dynamics of those cultures eventually.

5...Or, the ash lands on glaciers and the polar caps, thus causing them to absorb heat instead of reflecting, and excelerates global warming. Coatal flooding results, crop failures, mass die offs of animals and plants that are not heat tolerant. This could also cause a global shift in tropical plant species moving northward the northern hemisphere becomes warmer. This is already happening but on a very small scale.

6...The acidity of the oceans would increase from the sulfar rain washing into to streams and rivers that flow into the ocean, not to mention the ash landing in the sea. Ocean life will change with a lot of it dieing off. Good news, a nuclear winter might actually save coral reefs from bleaching out and dying...

All kinds of ways to treat a YS Caldera eruption and what happens 20 years afterwards would depend on what happened immediately after the eruption, say in the first 30 days or so.

Good luck...

Maggi, I found your question about the ash interesting. I was in in high school in Portland when Mt. St. Helens blew and then went to college in Seattle. So I was driving up and down I-5 a lot. The ash first choked the Toutle River almost completely and after they dredged it, they piled it up along the river next to the I-5 bridge. I was always fascinated watching the progress of nature there. And frankly, there wasn't much. Nothing grew on that pile until pretty recently and even now, it's just grass and maybe a few shrubby plants. The pile is probably 2 stories high? Hard to know whizzing by at 70 mph, but since another poster mentioned the depth of a likely SV ashfall, I thought I'd add that.

I think, since it's recent (as in, during the age of video coverage) you could take a look at Mt. St. Helens information/footage and extrapolate (by factors of thousands?) the extent of the damage from a super volcano. And ash must become earth over time but, again, based on seeing very little change in that pile over the last 32 years, it likely takes multiple hundreds of years. On the other hand, volcanic soil is great for growing certain crops so that could be a benefit.

One other thought: you do know that the basin of Naples Bay is a super volcano, right? Voila. Europe!

King Neptune said:

You could even use Iceland as the source instead of Yellowstone. Remember the problems created by one little volcano a few years ago. Multiply that by a few orders of magnitude and play with the idea. The mid-Atlantic ridge has been continually active for a very long time, and there is no reason why it couldn't increase enough to make Europe uninhabitable.
Then there's the Great Rift Valley, which isn't far to the South and East; there are many volcanoes along it, and a little more spreading could cause many more volcanoes.

There are a few other places where mid-oceans rifts are opening, and any of those could be used, unless you are writing non-fiction.

Click to expand...

Spreading-center volcanism is the least likely form to create a supervolcanic eruption. The real potential culprits are mantle-plume hotspots under continental crust (Yellowstone, Long Valley) or subduction-zone generated ones (Toba the most obvious example). These tend, for a variety of geologic reasons, to generate the most explosive magmas, and keep them trapped in magma chambers to build up over long periods of time.

Spreading-center volcanoes, and hotspot volcanoes under oceanic crust tend to have much more fluid lavas with less sticky silica and contained gases (Hawaii, most oceanic spreading-center localities). Even Iceland isn't a place prone to supervolcanic magma buildup, although it does appear to be situated over a mantle plume that coincides with the Atlantic spreading center. It does produce a lot of lava and ash and gases, and has been a source of serious trouble for northwestern Europe (the eruption of Laki in 1783-1784, in particular).

There are a dozen or so places in the world that are considered active supervolcanoes. In addition to those mentioned, there are a couple in Japan and a couple on the North Island of New Zealand.

caw

blacbird said:

Spreading-center volcanism is the least likely form to create a supervolcanic eruption. The real potential culprits are mantle-plume hotspots under continental crust (Yellowstone, Long Valley) or subduction-zone generated ones (Toba the most obvious example). These tend, for a variety of geologic reasons, to generate the most explosive magmas, and keep them trapped in magma chambers to build up over long periods of time.

Spreading-center volcanoes, and hotspot volcanoes under oceanic crust tend to have much more fluid lavas with less sticky silica and contained gases (Hawaii, most oceanic spreading-center localities). Even Iceland isn't a place prone to supervolcanic magma buildup, although it does appear to be situated over a mantle plume that coincides with the Atlantic spreading center. It does produce a lot of lava and ash and gases, and has been a source of serious trouble for northwestern Europe (the eruption of Laki in 1783-1784, in particular).

There are a dozen or so places in the world that are considered active supervolcanoes. In addition to those mentioned, there are a couple in Japan and a couple on the North Island of New Zealand.

caw

Click to expand...

I know what you mean. The mid-ocean ridges are not generally massive eruptions at any given time, but it appears that there may have been some tremendous volcanic activity in spreading centers in the far distant past.

I don't know how everyone else feels, but this is a great thread.

Just to throw this out...
If you're talking about Europe, you could also use the volcanoes in Italy. I am not a geologist by any means, but I wouldn't be surprised if there is a supervolcano in that region, as there are oodles of "regular" volcanoes - Mt. Vesuvius caused the troubles at Pompeii, some of Mt. Etna's eruptions were recorded by the Roman empire, and I know there are many more.

European calderas

melindamusil said:

Just to throw this out...
If you're talking about Europe, you could also use the volcanoes in Italy. I am not a geologist by any means, but I wouldn't be surprised if there is a supervolcano in that region, as there are oodles of "regular" volcanoes - Mt. Vesuvius caused the troubles at Pompeii, some of Mt. Etna's eruptions were recorded by the Roman empire, and I know there are many more.

Click to expand...

There is. It's not quite as 'super' as Yellowstone, but the Campi Flegrei caldera right next to Vesuvius is a similar type of caldera volcano. And it's active enough to worry the Italian volcanologists. I used to study geology and attended one field trip to Italy during the late 80's, and back then it had been less than a decade after the ground inside the caldera had risen quite a bit (fact check - seems to have been two meters), indicating that new magma had been filling the magma chamber there, and for a while scared the local geologists quite a bit - especially since nobody has witnessed a caldera eruption during the time there has been a science called 'geology' so nobody has any real data as what kind of signs might precede one of the big eruptions.

Campi Flegrei, or Phlegraean Fields, is not, as said, all that big compared to ones like Yellowstone, Long Valley or Toba, but if it had a large eruption it might be able to screw up most of Europe. Southern Italy would go for sure (definitely Napoli and everything close to it, one fun detail is that even the inside of the actual caldera is inhabited, and considering everything there is no way the locals would be able to evacuate even half of the people living in the area, especially, since, as said they don't even know what kind of signs would indicate that it is time to start that evacuation, or how much time they then would have for it if they happened to guess right in the first place and the thing actually was about to blow). And one thing Campi Flegrei is - a full eruption there would make the worst of Vesuvius look pretty minor stuff in comparison.

There is at least one another somewhere in Germany, if I remember right, but it's much less likely as a candidate, there is some activity there but nowhere close to what you get in Campi Flegrei. And right now I don't remember the name. If I find the details I'll post again.

Edit: hah, that didn't take long. Search 'Laacher See', that's the German one. But I would recommend Campi Flegrei as the culprit if you want to destroy Europe. You'd get at least half of northern Africa and Near East as a bonus too.

By the way, there are even larger eruption types than the big caldera eruptions, flood basalt (or trap basalt) eruptions. Search 'Siberian traps' and 'Deccan traps'. But then we are talking about something that can go on for as long as a million years and cause a major extinction event. Something some part of humanity might survive if they managed to get off planet in the first stages, especially if we go by the worst case scenario.

Might make an interesting catastrophe story, that.

Don't forget Santorini. Probably not large enough for your plot, but worth considering.

There is the caldera in the Czech Republic, but the hot spot isn't there any more.

http://www.jgeosci.org/content/jgeosci.071_2010_3_mlcoch.pdf

You might dream the hotspot into a different location.

maggi90w1 said:

Oh and while you're all here: Can you think of any other geological event that would cause world wide mass destructon?

Click to expand...

The obvious cataclysm would be an asteroid impact, something the size of the one that allegedly wiped out the dinosaurs, along with many other groups of organisms. That one is estimated to have been about 10km in maximum dimension. With something that size, where it struck the planet wouldn't matter.

caw