Sumatra, Earth's sixth-largest island, spied from space. CREDIT: NASA.
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 ...
Sumatra, Earth's sixth-largest island, spied from space. CREDIT: NASA.
Are you trying to cheer me up?
“However, there is wide disagreement about how early human were affected and whether large parts of the population were wiped out by the blast.”
Aren’t there theories that Toba wiped out all but about 12,000 of the human population of the planet?
Has anyone informed Al Gore about this?
Oh ... I remember, it’s all George Bush’s fault.
Not only this — too much www-ing causes hair to grow on the hands.
There’s some groundless speculation to that effect. :’)
Supervolcano Rained Acid on Both Poles -- But Wasn't So Bad After All?Scientists have long debated just how extensive and enduring those effects were. One study, for example suggested the Toba blast spawned a thousand-year ice age that only some 10,000 individuals survived. Another has found evidence of humans thriving in relatively nearby India shortly after the eruption.
by James Owen
National Geographic News
November 7, 2012
The new study -- based on acid rain-tainted ice cores from Antarctica and Greenland -- suggests Toba's fallout wasn't quite as catastrophic as might be expected.
The Antarctic ice core, for example, even bears traces of a warming event just after the Toba eruption -- contrary to a strong cooling signal seen in the Greenland cores.
"That means there's no long-term global cooling caused by the eruption," study co-author Anders Svensson said. If there had been, you'd expect to see evidence of a chill at both Poles.
In fact, the post-Toba Antarctic cooling spike looks well, relatively ordinary. "There may have been shorter [global] cooling of a duration of maybe 10 or 20 years, like we see for more recent" -- and much less powerful -- "volcanoes," said Svensson, of the Niels Bohr Institute's Centre for Ice and Climate in Copenhagen.
FMCDH(BITS)
Scientists Debate Toba Super-Eruption 74,000 Years Ago -- Did It Lead to Near Extinction of Homo-Sapiens?Now, a new study published in the journal Climate of the Past based on acid rain-tainted ice cores from Antarctica and Greenland, suggests Toba's wasn't effect quite as catastrophic as might be expected. The Antarctic ice core shows traces of a warming event soon after the Toba eruption in contrast to vivid cooling signs found in the Greenland ice cores.
dr burke
Daily Galaxy
November 08, 2012
"That means there's no long-term global cooling caused by the eruption," study co-author Anders Svensson of the Niels Bohr Institute's Centre for Ice and Climate in Copenhagen said. If there had been, you'd expect to see evidence of a chill at both Poles. There may have been shorter cooling of a duration of maybe 10 or 20 years, like we see for more recent and much less powerful volcanoes."
Call me nully furrypaws...
Paging Al Gore, Mr. Al Gore, please pick up the white courtesy phone you have an important message from Current TV.
I think Brian Williams on NBC has a segment on internet abuse and how you can tell if your a victim? AUSM? (are you sh!tting me?)
There are shorter warm spells in the midst of the icy periods ~ Toba might well have occurred during such a period, or could have influenced it in some way.
Ha Ha, right you are!
I would personally like to view the photo’s, charts & graphs from this event that happened, per the article, 74,000 years ago. Just for comparisons doctor!
“That Supervolcano was the result of the TEA PARTY, Bush and the Republicans in Congress,” Obama said today!!
“Aren’t there theories that Toba wiped out all but about 12,000 of the human population of the planet?”
This (74,000 years ago) predates human existance by about 68,000 years...how could there be 12,000 of the human population as survivors? :)
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