Posted on 04/30/2006 4:35:48 PM PDT by blam
Ice Ages Blamed on Tilted Earth
By Michael Schirber
LiveScience Staff Writer
posted: 30 March 2005
In the past million years, the Earth experienced a major ice age about every 100,000 years. Scientists have several theories to explain this glacial cycle, but new research suggests the primary driving force is all in how the planet leans.
The Earth’s rotation axis is not perpendicular to the plane in which it orbits the Sun. It's offset by 23.5 degrees. This tilt, or obliquity, explains why we have seasons and why places above the Arctic Circle have 24-hour darkness in winter and constant sunlight in the summer.
But the angle is not constant – it is currently decreasing from a maximum of 24 degrees towards a minimum of 22.5 degrees. This variation goes in a 40,000-year cycle.
Earth's Wobble ...
.
... is like the precession of a spinning top.
IMAGE: NASA
Peter Huybers of Woods Hole Oceanographic Institution and Carl Wunsch of the Massachusetts Institute of Technology have compared the timing of the tilt variations with that of the last seven ice ages. They found that the ends of those periods – called glacial terminations – corresponded to times of greatest tilt.
"The apparent reason for this is that the annual average sunlight in the higher latitudes is greater when the tilt is at maximum," Huybers told LiveScience in a telephone interview.
More sunlight seasonally hitting polar regions would help to melt the ice sheets. This tilt effect seems to explain why ice ages came more quickly – every 40,000 years, just like the tilt variations -- between two and one million years ago.
"Obliquity clearly was important at one point," Huybers said.
Colder planet
The researchers speculate that the glacier period has become longer in the last million years because...
(Excerpt) Read more at livescience.com ...
These guys are reporting these facts like they are some kind of major breakthrough revelation.
This has been scientific fact for decades now but for some reason the climatologists know nothing about it.
As the icebergs melt, the earth becomes less dense, which in turn, accelerates its revolutions. Days become shorter, but worse yet, larger objects will have a tendency to escape earth's atmosphere as gravity diminishes.
OK, I'm still working on the details./s
"The last major glacial thaw was 10,000 years ago, which means that the Earth is scheduled to head into another ice age. Whether human influences could reverse this, Huybers was hesitant to speculate. Other researchers have found evidence that the process of climate warming can set up conditions that create a global chill."
Try telling Algore that.
Yes, but was the earth always on a tilt?
""Earth’s axis is currently pointing at the North Star, Polaris, but it is always rotating around in a conical pattern. In about 10,000 years, it will point toward the star Vega, which will mean that winter in the Northern Hemisphere will begin in June instead of January."
That's quite a statement, and what happens in the intermediary time when the seasons are shifting?
Interesting re-introduction of a interesting theory of thirty years ago by Fred Hoyle et al.
Maybe so, but note that the global warming will not negate global cooling, if fact, the report says, global warming will augment global cooling and sooner usher in the comming age of ice.
I'll tell you, good freepers, these science fellows are fast on their feet.
I agree. They left out the marked periodicity of the sun. This smells like a political story.
This is all spin, as far as I am concerned. Spin-doctors get way too much money for far too little work.
Guess you went to government schools.
Women and minorities hardest hit...
Think about a scenario where there was no tilt at all of the earth's axis.
There would be no seasons anywhere on the planet (a slight change in our summer since the earth is slightly farther from the sun.)
But at the poles, it would just be constant sunset all the time, 24 hours a day every day. With the thicker atmosphere that the little amount of sunlight has to go through, it would be 40, 50 degrees below zero all the time, 24 hours a day, day in day out.
There would be no melting of any snow that falls at the poles. Massive glacial sheets would build up, flow south (and north) and the top third and bottom third of the planet would be just one big glacial sheet.
Just the tilt moving from 24 degrees to 22.5 degrees can leave an effect which could be similar (when combined with other cycles.)
Just having a continent over the poles like Antarctic and Greenland/Baffin Island can cause glaciers to build up. 600 million years ago, most of the continents were locked up together over the south pole and nearly the entire planet froze over (even the oceans.)
Like I said, none of this has ever been taught to any climatologist.
LOL
They only have 100 years to work with because they, like the rest of us, will be dead.
"There would be no melting of any snow that falls at the poles."
If there were no evaporation at the poles there would be no clouds from which snow could fall.
>>>In the past million years, the Earth experienced a major ice age about every 100,000 years.<<<
Reminds me of a time when a frantic lady called into a talk show and asked the guest, Carl Sagan, "When did you say the sun would expand and engulf the earth?"
"In about 10 billion years," Sagan replied.
"Thank God," said the caller. "I thought you said 10 million!"
Or it could be be some intelligent design so that life could be supported on the planet . . . .
That's why severe cold periods are always so dry.
And doesn't it tilt in different directions at different times? Oh, wait, maybe Atlas is just shifting from one leg to the other.
All we need to do is figure out how to tilt the earth just a bit.
Ever see those political cartoons lampooning gas prices? Those SUVs are friggin' HUGE! If U.S. consumers buy just a few more thousand of those babies, North America will obvious become so heavy relative to Asia on the other side of the planet that the earth will lean toward the heavy side. Tilted earth = cooldown to counteract the "greenhouse effect". Problem solved.
How's that for junk science? Right up there with global warming "theories" based upon computer models that can't even get the weather right 2 or 3 days in advance, much less years or centuries.
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