Dryas all wet
http://www.nature.com/news/2009/091012/full/news.2009.997.htmlNorth America comet theory questioned
No evidence of an extraterrestrial impact 13,000 years ago, studies say.
by Rex Dalton
An independent study has cast more doubt on a controversial theory that a comet
exploded over icy North America nearly 13,000 years ago, wiping out the Clovis
people and many of the continent's large animals. ...
References
1. Surovell, T. A. et al. Proc. Natl Acad. Sci. USA advance online
publication doi:10.1073/pnas.0907857106 (2009).
2. Firestone, R. B. et al. Proc. Natl Acad. Sci. USA 104, 16016-16021
(2007).
3. Marlon, J. R. et al. Proc. Natl Acad. Sci. USA 106, 2519-2524
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4. Kennett, D. J. et al. Proc. Natl Acad. Sci. USA 106, 12623-12628
(2009).
http://arstechnica.com/science/news/2009/10/irreproducible-results-raise-doubts-about-ice-age-impact.ars
Asteroid impact-driven climate change called into question
In recent years, a team of researchers has been gathering evidence of an
extraterrestrial impact that occurred precisely as the Earth plunged into a cold
snap. Now, other researchers have tried to reproduce a key piece of that
evidence, and apparently failed.
By John Timmer | Last updated October 12, 2009 3:11 PM CT
The end of the last ice age was a busy time in North America. As a whole, the
world seemed to be in the process of exiting the long cold snap nearly 15,000
years ago, but there was a sudden return to icy conditions that lasted nearly
2,000 years. At about the same time, the first humans made their presence felt
in North America, and many of the larger species of fauna went extinct. ...
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