Posted on 03/07/2010 4:42:38 PM PST by Ernest_at_the_Beach
Geologists have found evidence that sea ice extended to the equator 716.5 million years ago, bringing new precision to a "snowball Earth" event long suspected to have taken place around that time.
In this photo from Canada's Yukon Territory, an iron-rich layer of 716.5-million-year-old glacial deposits (maroon in color) is seen atop an older carbonate reef (gray in color) that formed in the tropics. (Credit: Francis A. Macdonald/Harvard University)
Led by scientists at Harvard University, the team reports on its work in the journal Science. The new findings -- based on an analysis of ancient tropical rocks that are now found in remote northwestern Canada -- bolster the theory that our planet has, at times in the past, been ice-covered at all latitudes.
"This is the first time that the Sturtian glaciation has been shown to have occurred at tropical latitudes, providing direct evidence that this particular glaciation was a 'snowball Earth' event," says lead author Francis A. Macdonald, an assistant professor in the Department of Earth and Planetary Sciences at Harvard. "Our data also suggests that the Sturtian glaciation lasted a minimum of 5 million years."
The survival of eukaryotic life throughout this period indicates sunlight and surface water remained available somewhere on the surface of Earth. The earliest animals arose at roughly the same time, following a major proliferation of eukaryotes.
Even in a snowball Earth, Macdonald says, there would be temperature gradients on Earth and it is likely that ice would be dynamic: flowing, thinning, and forming local patches of open water, providing refuge for life.
(Excerpt) Read more at sciencedaily.com ...
fyi
o here we go...
FR Thread:
In Denial ( The meltdown of the climate campaign.
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And some History on how the AGW Campaign started....FR Thread:
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You need to read this as to how the Global Warming campaign came to be....heard of Maurice Strong...see this thread:
Global Warming The Anthropocentric Crisis
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Global Warming is Not a Proven Fact
Simply put, climate change – originally an emerging new ice age, then global warming and now climate change – is not a proven fact. To sarcastically mimic the affected gravitas of certain warming experts, we might call it an “anthropocentrically manufactured” issue.
As mentioned in Part 2, in the late 1960’s the United Nations assigned Canadian Maurice Strong, a man possessed of a strong belief in the merits of global governance and the need to establish transnational governmental institutions, to head up what subsequently came to be known as the global climate change initiative.
Mr. Strong, aptly named in spite of possessing the forgettable demeanour of a faceless bureaucrat, has had a successful career as an entrepreneur, businessman and government executive building impressive business and political connections throughout the world. His skills and contacts have made him personally wealthy. He has been able to knit together an extremely effective network of the world’s decision makers in both government and business. While ideologically anchored, he is a master pragmatist in the pursuit of his objectives.
See updates.
'Snowball Earth': Glaciers, ice packs once met at Equator
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American boffins say they have discovered evidence that almost the entire world was covered in sea ice and glaciers at certain points in the remote past, during so-called "snowball Earth" periods where the polar ice sheets met at the Equator.
It were grim in the old days.
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Source is a UK publication...boffins ...are Scientists....
See #7 also!
We better get busy keeping this rock warm!
I do not like cold weather.
Atmospheric Carbon Dioxide and Interglacial Warmth ( Youtube)
We are a few thousand years overdue for some chilling!
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I like the warm much better, preferably over 75. ;)
Thanks for the link. Had to replace my box and lost many of my GW links.
I know, that’s the scary part. Can’t move much further south and still be in the USA.
Welcome to Hoth. B-)
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