Posted on 08/07/2009 1:53:39 PM PDT by decimon
In a publication to be released Friday in the journal Science, researchers from Oregon State University and other institutions conclude that the known wobbles in Earth's rotation caused global ice levels to reach their peak about 26,000 years ago, stabilize for 7,000 years and then begin melting 19,000 years ago, eventually bringing to an end the last ice age.
The melting was first caused by more solar radiation, not changes in carbon dioxide levels or ocean temperatures, as some scientists have suggested in recent years.
"Solar radiation was the trigger that started the ice melting, that's now pretty certain," said Peter Clark, a professor of geosciences at OSU. "There were also changes in atmospheric carbon dioxide levels and ocean circulation, but those happened later and amplified a process that had already begun."
The findings are important, the scientists said, because they will give researchers a more precise understanding of how ice sheets melt in response to radiative forcing mechanisms. And even though the changes that occurred 19,000 years ago were due to increased solar radiation, that amount of heating can be translated into what is expected from current increases in greenhouse gas levels, and help scientists more accurately project how Earth's existing ice sheets will react in the future.
(Excerpt) Read more at physorg.com ...
Wobbly ping.
They finally have come to accept that the Sun gives off heat that warms the Earth. What a great leap of science there. /s
warms the cockles of my heart
Translation - all that effort and they still refuse to learn from history - that solar radiation changes are what is driving current climate cycling.
What is this journal “Science” they refer to? Don’t they know that real climate news comes by way of People, USA Today, and Katie Couric? /sarc
They say that the sun caused previous warming trends but they must learn how that happened to know more about the current man caused trend. I don’t think they are giving up anything by a partial condescension to the truth.
It’s encouraging to see some recognition of basic reality. This global warming garbage has been so far out there any move towards sanity is welcome IMO.
Translation - all that effort and they still refuse to learn from history - that solar radiation changes are what is driving current climate cycling.
What I find amazing is that they are off by 13,000 years. The great lakes were formed a mere 6,000 years ago, accurately measured by the erosion taking place at Nigeria Falls. They found the interior of the falls erodes 3 ft a year, simple math calculates 6,000 year (stunning many scientists). A sheet of glacial ice covered over half the United less than 6,000 years ago. If they can’t even get this right, how correct can their assumptions be?
John Costello (20:02:49) :
Back in the bad old days of the Soviet evil Empire scientists in most disciplines had to bend the knee to Marxism. It was often qutie amusing. They would spend the first few paragraphs declaring their allegiance to Karl and Vlad (and the Great Teacher of Humanity Joseph Stalin) and then go on to describe their research in paleontology, math, archaeology, etc., which had absoluteoy nothing to do with Marxism. Some fields suffered more than most: archaeologists had to create a new culture in 4th century Ukraine to replace the Ostrogothic state, and Russian SF was denied Einstinian time dilation because Lenin didnt like it. Something similar seems to be happening here, in as much as Science or Nature will not publish deniers and yoiu cant get NSF funding (and thus tenure) if you are on the outs with the Goracle.
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http://www.archive.org/stream/earthupheaval010880mbp/earthupheaval010880mbp_djvu.txt
EARTH IN UPHEAVAL
Excerpt:
“While the question of the age of the falls thus becomes
complicated, the discovery shows that the post-glacial
period was of much shorter duration than generally as-
sumed, even if the rate of retreat of the falls is reduced
to the minimum figure of under four feet per year, as
observed in more recent years. R. F. Flint of Yale writes:
“We are obliged to fall back on the Upper Great
Gorge, the uppermost segment of the whole gorge, which
appears to be genuinely postglacial. Redeterminations by
W. H. Boyd showed the present rate of recession of the
Horseshoe Falls to be, not five feet, but rather 3.8 feet,
per year. Hence the age of the Upper Great Gorge is cal-
culated as somewhat more than four thousand years
and to obtain even this [low] figure we have to assume
that the rate of recession has been constant, although we
know that discharge has in fact varied greatly during post-
glacial times.” 4 Jt due allowance is made for this last
factor, the age of the Upper Great Gorge of Niagara
Falls would be somewhere between 2500 and 3500 years.
It follows that the ice retreated in historical times, some-
where between the years 1500 and 500 before the present
era.
Thanks!
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