Thanks blam. I'd seen this somewhere, I thought it was strange I couldn't find it again, apparently it was not previously posted. [blush]
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Posted on 02/13/2018 10:06:52 AM PST by blam
UNIVERSITY OF ARIZONA—The massive Toba volcanic eruption on the island of Sumatra about 74,000 years ago did not cause a six-year-long "volcanic winter" in East Africa and thereby cause the human population in the region to plummet, according to new University of Arizona-led research.
The new findings disagree with the Toba catastrophe hypothesis, which says the eruption and its aftermath caused drastic, multi-year cooling and severe ecological disruption in East Africa.
"This is the first research that provides direct evidence for the effects of the Toba eruption on vegetation just before and just after the eruption," said lead author Chad L. Yost, a doctoral candidate in the UA Department of Geosciences. "The Toba eruption had no significant negative impact on vegetation growing in East Africa."
Researchers can use ancient plant parts that wash into and accumulate on the bottoms of lakes to reconstruct a region's past ecosystem. Yost and his colleagues studied microscopic bits of plants preserved in two sediment cores from Lake Malawi, which is approximately 570 kilometers (354 miles) long and is the southernmost of the East African Rift lakes.
Previous investigators found material from the Toba eruption in the Lake Malawi cores. That material pinpoints the time of the eruption and allowed Yost and colleagues to peer back in time 100 years before to 200 years after the Toba eruption. The team analyzed samples that represented, on average, every 8.5 years within that 300-year interval.
"It is surprising," Yost said. "You would have expected severe cooling based on the size of the Toba eruption--yet that's not what we see."
Yost and his colleagues did not find marked changes in lower-elevation vegetation post-eruption. The team did find some die-off of mountain plants just after the eruption. Cooling from the eruption might have injured frost-intolerant plants, he said.
Had the region experienced the drastic, multi-year cooling post-Toba, the cores would have evidence of a massive die-off of the region's vegetation at all elevations, Yost said.
Part of the Toba catastrophe hypothesis suggests the eruption caused human populations to shrink.
(snip)
Late Pleostocene Human Population Bottlenecks. . . (Toba)
"The last glacial period was preceded by 1000 years of the coldest temperatures of the Late Pleistocene, apparently caused by the eruption of the Mount Toba volcano. The six year long volcanic winter and 1000-year-long instant Ice Age that followed Mount Toba's eruption may have decimated Modern Man's entire population. Genetic evidence suggests that Human population size fell to about 10,000 adults between 50 and 100 thousand years ago. The survivors from this global catastrophy would have found refuge in isolated tropical pockets, mainly in Equatorial Africa. Populations living in Europe and northern China would have been completely eliminated by the reduction of the summer temperatures by as much as 12 degrees centigrade. "
(snip)
Conclusion: Volcanic eruptions drastically affect the earth’s climate, except when they don’t...
The truth:
“I know nothing.” — Jon Snow, meteorologist of Winterfell
Thanks blam. I'd seen this somewhere, I thought it was strange I couldn't find it again, apparently it was not previously posted. [blush]
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Nyah nyah, told ya. Oops, I mean, thanks blam. ;^) Yellowstone's eruption would be much better if it were right under the mayor of San Juan's house, while she's home.
Have you ever looked at this site? http://www.suspicious0bservers.org/
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