Posted on 03/05/2010 12:55:48 PM PST by Ernest_at_the_Beach
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.
Geologists probing conditions seen in the ancient world have long considered that there was a cold spell known as the Sturtian Glaciation about 716 million years ago. However there has been disagreement in boffinry circles as to just how severe this glaciation was.
Now, researchers from Harvard uni in the States, funded by the US government, say they have found ironclad proof that there were glaciers right down on the Equator at that time. Tropical rocks from the Sturtian, which have since migrated up to remote northwestern Canada, show unmistakable signs of having been covered in big ice back then.
"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 geology brainbox Francis Macdonald of Harvard.
"Our data also suggest that the Sturtian glaciation lasted a minimum of five million years," he adds.
"Ice may have covered the entire planet then," comments Enriqueta Barrera, federal science bigwig, "turning it into a 'snowball Earth'."
(Excerpt) Read more at theregister.co.uk ...
Must have been a short growing season.
The global warming people want us to go back to that?
You can apparently watch an entire program on this subject here (in five 10-min parts):
2001 BBC Horizon Snowball Earth part 1 of 5:
http://www.youtube.com/watch?v=HG5_ufWfbuk
Sounds like Algore’s ancestors were asleep at the wheel. Probably swinging through the trees and eating frozen bananas.
Canada (where I live), was buried under a two-mile thick icecap, until about 8,000 years ago. I have yet to hear any AGW alarmist explain why having that icecap melt was a bad thing. If I lived in (say) Arizona, I would probably appreciate ice more — preferably in a tall glass.
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)
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This work was supported by the Polar Continental Shelf Project and the National Science Foundation's Geobiology and Environmental Geochemistry Program.
Planet earth prosper during warming trends and dies off during ice ages. The more we can put off the next ice age the better. Al Gore be damned!!!!
Why all these references to geniuses? “Boffinry”, “Brainbox”; I know it’s British, but it reads like something from the Weekly World News.
Carbon Dioxide Helped Ancient Earth Escape Deathly Deep Freeze
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ScienceDaily (Dec. 8, 2008) — The planet’s present day greenhouse scourge, carbon dioxide, may have played a vital role in helping ancient Earth to escape from complete glaciation, say scientists in a paper published online today.
In their review for Nature Geoscience, UK scientists claim that the Earth never froze over completely during the Cryogenian Period, about 840 to 635 million years ago.
This is contrary to the Snowball Earth hypothesis, which envisages a fully frozen Earth that was locked in ice for many millions of years as a result of a runaway chain reaction that caused the planet to cool.
What enabled the Earth to escape from a complete freeze is not certain, but the UK scientists in their review point to recent research carried out at the University of Toronto. This speculates that the advancing ice was stalled by the interaction of the physical climate system and the carbon cycle of the ocean, with carbon dioxide playing a key role in insulating the planet.
The Toronto scientists say that as Earth’s temperatures cooled, oxygen was drawn into the ocean, where it oxidized organic matter, releasing the greenhouse gas carbon dioxide into the atmosphere.
The review’s lead author, Professor Phillip Allen, from Imperial College London’s Department of Earth Science and Engineering, says that something must have kept the planet’s equatorial oceans from freezing over. He adds: “In the climate change game, carbon dioxide can be both saint and sinner. These days we are so concerned about global warming and the harm that carbon dioxide is doing to our planet. However, approximately 600 million years ago, this greenhouse gas probably saved ancient Earth and its basic life forms from an icy extinction.”
Professor Allen, whose previous research has found evidence demonstrating hot and cold cycles in the Cryogenian period, says a plethora of papers has been published and much debate has been devoted to the Snowball Earth theory since it was originally proposed. He says:
The idea being that these rather large deposits, boulders, etc, were embedded in advancing glaciers, portions of which stretched out into the sea. Then, when the ice melted, they were dropped onto the seafloor (carbonate reef).
Sounds more like a “settled science” pipe dream.
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From Wikipedia, the free encyclopedia
This article is about the British slang word for scientist. For other uses of the word,
In the slang of the United Kingdom, Australia, New Zealand, India and South Africa, boffins are scientists, medical doctors, engineers, and other people engaged in technical or scientific research. The word 'boffin' (or 'boff'—often as an insult[1]) can also be used to refer to any particularly clever person. The closest American equivalent is "egghead".[2]
I got to tell ya, that the more crap I see coming out from the ‘scientific community’ the more I want to ignore the whole group. they make stuff up and try to sell their theory as scientific fact.
I wonder if there is enough water on the planet to cover the planet with a mile deep ice cover.
Now the AGW crowd seems to make stuff up.
New Evidence Puts 'Snowball Earth' Theory Out In The Cold
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ScienceDaily (Mar. 25, 2007) — The theory that Earth once underwent a prolonged time of extreme global freezing has been dealt a blow by new evidence that periods of warmth occurred during this so-called 'Snowball Earth' era.
Analyses of glacial sedimentary rocks in Oman, published online in Geology, have produced clear evidence of hot-cold cycles in the Cryogenian period, roughly 850-544 million years ago. The UK-Swiss team claims that this evidence undermines hypotheses of an ice age so severe that Earth's oceans completely froze over.
Using a technique known as the chemical index of alteration, the team examined the chemical and mineral composition of sedimentary rocks to search for evidence of any climatic changes. A high index of alteration would indicate high rates of chemical weathering of contemporary land surfaces, which causes rocks to quickly decompose and is enhanced by humid or warm conditions. Conversely, a low chemical index of alteration would indicate low rates of chemical weathering during cool, dry conditions.
The researchers found three intervals with evidence for extremely low rates of chemical weathering, indicating pulses of cold climate. However these intervals alternate with periods of high rates of chemical weathering, likely to represent interglacial periods with warmer climates.
These warmer periods mean that, despite the severe glaciation of this time in Earth history, the complete deep-freeze suggested by 'Snowball Earth' theories never took place, and that some areas of open, unfrozen ocean continued to exist. Leader of the study, Professor Philip Allen of Imperial College London's Department of Earth Science and Engineering, explains:
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