Skip to comments.'True polar wander' may have caused ice age
Posted on 11/20/2018 5:32:39 PM PST by BenLurkin
Like any spinning object, Earth is subject to centrifugal force, which tugs on the planet's fluid interior. At the equator, where this force is strongest, Earth is more than 26 miles larger in diameter than at the poles. Gordon said true polar wander may occur when dense, highly viscous bumps of mantle build up at latitudes away from the equator.
If the mantle anomalies are massive enough, they can unbalance the planet, and the equator will gradually shift to bring the excess mass closer to the equator.
The planet still spins once every 24 hours and true polar wander does not affect the tilt of the Earth's spin axis relative to the sun. The redistribution of mass to a new equator does change Earth's poles, the points on the planet's surface where the spin axis emerges.
Earth is still in an ice age that began about 3.2 million years ago. Earth's poles have been covered with ice throughout the age, and thick ice sheets periodically grow and recede from poles in cycles that have occurred more than 100 times. During these glacial cycles, ice has extended as far south as New York and Yellowstone National Park. Earth today is in an interglacial period in which ice has receded toward the poles.
Gordon said true polar wander is not merely a change in the location of Earth's magnetic poles.... The paleomagnetic record, which is often used to study the movement of tectonic plates across Earth's surface, contains many instances of "apparent polar wander," which tracks the motion of the spin axis and which includes the effects of both plate motion and true polar wander, Gordon said
(Excerpt) Read more at phys.org ...
If only the woolly mammoths hadn’t all run to one side and tipped over the planet.
How many trillions do we have to ship to China and India to stop this Algore?
So, I have recently read that Earth is swallowing TRILLIONS of tons of water into its interior as tectonic plates collide beneath the ocean.
I wonder if this could cause enough unbalance to make another polar wander.
Sounds like Stormy Daniels to me. Is this guy REALLY a geologist?
Wow, that is truly astonishing. I thought there were a couple Ice Ages with the Pleistocene being the last one and ending about 10,000 years ago. That's the first I've heard that we've been through 100 cycles of ice sheet advance/retreat and we are still in an ice age that began 3.2 million years ago.
How in the world can they determine we've been through more than 100 cycles? Wouldn't each glaciation period wipe out evidence of all former glaciations? When you see glacial striations on bedrock and the vast terminal moraines in upstate NY, you get a real sense for the power of glaciers to wipe everything out.
Earth is still in an ice age that began about 3.2 million years ago.
A fact that Al Gore doen’t want you to know.
Paging Charles Hapgood.
Is Santa OK?
I mean, Ive been really good this year and Im just sure Im on the Nice list.
Its been a real struggle what with Nancy Pelosi and Joy Behar and Hillary and Obama and all those other assho.....I mean people.
Ive never wanted to kick so many people on their behinds.
But, I maintained my calm.....except for that incident with my neighbor Steve and the rake. But he had it coming! His stupid leaves were all over my lawn!
Theres no trees at the North Pole, so Santa cant truly understand how annoying leaves are.
Well, I hope hes OK.
Santa, not Steve. Steve can stick leaves up his, well, whatever.
And Santa better not be bringing me a rake for Christmas or hell find out what rake tastes like.
See....now Im on the Naughty list.....and its not even Thanksgiving yet.
Right! Earth's Shifting Crust.
The end of the Younger Dryas, about 11,500 years ago, was particularly abrupt. In Greenland, temperatures rose 18°F in a decade.These things really put the global warming hysteria in perspective.
Around 8,200 years ago, however, a surprising event occurred. The 8.2 ka event, was first discovered in the Greenland ice core GISP2, where high-resolution analyses indicate that over two decades temperature cooled about 6°F in Greenland. The entire event lasted about 150 years and then temperatures warmed, returning to their previous levels.
I saw that article as well. Problem is it didn't go on to explain that it's all part of a CYCLE. A very large and complex cycle.
No. There are other indications in sediment in the ocean and fossil record.
The oceans rise and fall through an ice age cycle.
There is quite a bit of evidence of multiple ice ages.
It has been a mystery what caused them to start.
This theory takes a stab at it.
All of human existence is in the ice age and interglacials.
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