Posted on 11/08/2012 6:20:32 PM PST by SunkenCiv
About 74,000 years ago, the Toba volcano on the Indonesian island of Sumatra erupted with catastrophic force. Estimated to be 5,000 times larger than the 1980 eruption of Mount St. Helens, it is believed to be the largest volcanic event on Earth in the last 2 million years.
Toba spewed enough lava to build two Mount Everests, it produced huge clouds of ash that blocked sunlight for years, and it the left behind a crater 31 miles (50 kilometers) across. The volcano even sent enough sulphuric acid into the atmosphere to create acid rain downpours in the Earth's polar regions, which researchers have found evidence of in deep ice cores.
"We have now traced this acid rain in the ice caps on Greenland and Antarctica," glaciologist Anders Svensson, of the Niels Bohr Institute at the University of Copenhagen, said in a statement.
"We have long had an idea of at what depth the Toba eruption could be found in the Greenland ice cap, but we found no ash, so we could not be sure," Svensson added. "But now we have found the same series of acid layers from Toba in the Greenland ice sheet and in the ice cap in Antarctica. We have counted the annual layers between acid peaks in ice cores from the two ice caps and it fits together."
...The study is detailed in the journal Climate of the Past.
(Excerpt) Read more at livescience.com ...
Great thread! Thanks!
That’s anice big round hole in the lower right. Is that the volcano, asteroid hit, fishing pond?
LOL. Boy are you right! In fact, it wouldn’t surprise me if they name a fault after GW.
Yes, there are such theories. Also, the crater left by Toba is about 16 by 65 miles.
I’m no scientist, so feel free to chime in here, but... wouldn’t this have caused the sort of “nuclear winter” they’re always talking about with reference to a nuclear war - the clouds eliminating all sunlight until all the plants died and so on?
I mean, so why wasn’t everything extinct after this?
We WERE extinct.
But we got better.
That’s a good point — the fact that it didn’t have that kind of effect goes to show just how pipsqueakish ALL volcanic eruptions are compared with impacts by large pieces of space debris. It’s remarkable how mealy-mouthed this is carried out — oh, the Chicxulub impact didn’t do anything *because dinosaurs were already in the _process_ of going extinct* (emphasis on stuff that makes no sense, more emphasis on stuff that really makes no sense), but this big eruption field called the Deccan Traps caused the mass extinction. Meanwhile this 70K year old supereruption caused the (entirely imaginary) genetic bottleneck in the human species, and only them, and we know its exact extent, era, and duration. Ridiculous.
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