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Ice ages: Why North America is key to their coming and going
Christian Science Monitor ^ | August 7, 2013 | Pete Spotts

Posted on 08/11/2013 6:07:09 AM PDT by SunkenCiv

Scientists have long tried to figure out what causes the ebb and flow of ice ages. New data suggests a novel explanation for why the mile-thick blankets of ice retreat so quickly: They become too heavy.

For the last 900,000 years, mile-thick ice sheets have waxed and waned in the Northern Hemisphere with remarkable regularity – building over periods of about 100,000 years and retreating in the space of only a few thousand years, only to repeat the cycle.

Now, a team of scientists from Japan, the US, and Switzerland suggests that the North American continent is the breeding ground for these cycles. It's a region where climate and the ice's effect on the Earth's crust play off each other to draw out the length of a glacial cycle triggered by changes in solar radiation that come with changes in Earth's orbit.

This feedback between climate and ice becomes most dramatic at the end of the cycle, when an ice sheet that has bulldozed its way too far south and gotten too heavy for its own good meets up with a warming climate.

(Excerpt) Read more at csmonitor.com ...


TOPICS: Astronomy; Science
KEYWORDS: antarctica; catastrophism; climate; glaciation; globalwarming
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To: SunkenCiv

The rain forests cause more CO2 than North American continent.


21 posted on 08/11/2013 8:41:44 AM PDT by Vaduz
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To: ClearCase_guy

Ice build up does not affect orbital eccentricity, nor substantially affect axial tilt or orientation. An ellipse with an eccentricity of 0.0 is a circle. The solution to the two body problem in Newtonian mechanics is conic section: orbits are either ellipses (a circle being a special case), parabolas or hyperbolas. For bodies which are graviationally bound (specific orbital energy < 0) they are ellipses, for bodies not gravitationally bound (soe >0) they are hyperbolas. For the case of soe = 0, parabolas.

There is a really nice introduction to orbital mechanics, by Bates, Mueller and White, “Introduction to Astrodynamics”, if you are interested.


22 posted on 08/11/2013 8:55:18 AM PDT by Lonesome in Massachussets (Doing the same thing and expecting different results is called software engineering.)
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To: ClearCase_guy
The orbital eccentricity is due to the effects of the gravitational pull of Jupiter and Saturn - not ice buildup.
23 posted on 08/11/2013 9:37:11 AM PDT by DuncanWaring (The Lord uses the good ones; the bad ones use the Lord.)
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To: meatloaf
Eventually simple strength of materials tell us that the shelf is going to break off.

1960's-era "World Book" encyclopedias contain references to ice floes the size of Delaware; giant floes/bergs are by no means a modern phenomenon.

24 posted on 08/11/2013 9:39:45 AM PDT by DuncanWaring (The Lord uses the good ones; the bad ones use the Lord.)
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To: Lonesome in Massachussets

“Introduction to Astrodynamics”

It’s rare to encounter a reference to that book. Where’d you run into it?


25 posted on 08/11/2013 9:43:23 AM PDT by DuncanWaring (The Lord uses the good ones; the bad ones use the Lord.)
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To: DuncanWaring

My bad:

http://www.amazon.com/Fundamentals-Astrodynamics-Dover-Aeronautical-Engineering/dp/0486600610

“Fundamentals”, could have been called introduction. It’s pretty much on an advanced undergraduate level. Somewhat dated, but a solid and gentle introduction.


26 posted on 08/11/2013 9:49:13 AM PDT by Lonesome in Massachussets (Doing the same thing and expecting different results is called software engineering.)
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To: Lonesome in Massachussets

I know all that; I’ve got a copy. ;-)

I was wondering how it came to your attention.


27 posted on 08/11/2013 9:52:39 AM PDT by DuncanWaring (The Lord uses the good ones; the bad ones use the Lord.)
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To: DuncanWaring

They tried to work CO2 into the mix for political reasons. It did not work. I would say based on this type of work 50% of the study is right and 50% is wrong.


28 posted on 08/11/2013 10:53:16 AM PDT by spawn44 (MOO)
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To: SunkenCiv

This whole theory and the article has to be untrue.

Everyone knows that all climate change is caused by humans and most importantly by the actions of George Bush during his 8 years in office.

He is a genocidal maniac and will be responsible for the death of untold millions and the ruination of miles of seashore estates of the rich and famous unless we immediately listen to ALGORE and the OBAMABOTS


29 posted on 08/11/2013 10:55:38 AM PDT by wildbill
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To: adorno

I had a similar feeling. The ice ages and global warming are all America’s fault /s
I couldn’t find an estimate based on their model - when is the next ice age supposed to start?


30 posted on 08/11/2013 1:12:57 PM PDT by tbw2
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To: DuncanWaring

Were I work, it was a common reference in the 1980’s. It was either Bates, Mueller & White, or Pedro
Ramon Escobal. http://www.amazon.com/Methods-Orbit-Determination-Pedro-Escobal/dp/0882753193


31 posted on 08/12/2013 3:56:28 AM PDT by Lonesome in Massachussets (Doing the same thing and expecting different results is called software engineering.)
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To: tbw2

Don’t know about “ice age”, but based on observations of the sun’s magnetic activity, expect the earth to be noticably cooler within the next decade.


32 posted on 08/12/2013 6:05:48 AM PDT by DuncanWaring (The Lord uses the good ones; the bad ones use the Lord.)
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To: Lonesome in Massachussets

I ran into it as the textbook for a course I took in college; the authors were members of the faculty.


33 posted on 08/12/2013 6:07:23 AM PDT by DuncanWaring (The Lord uses the good ones; the bad ones use the Lord.)
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To: DuncanWaring

Small institution in Colorado Springs? The book was something of an industry standard for folks who only needed to understand the basics. Not space mission planners, but the folks designing sensors like radar.


34 posted on 08/12/2013 12:42:05 PM PDT by Lonesome in Massachussets (Doing the same thing and expecting different results is called software engineering.)
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To: Lonesome in Massachussets

A little trade-school at the base of the Rocky Mountains.


35 posted on 08/12/2013 12:50:17 PM PDT by DuncanWaring (The Lord uses the good ones; the bad ones use the Lord.)
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To: DuncanWaring

Yeah, worked with some of its alums. Good crew, hardly a bad egg among them.


36 posted on 08/12/2013 12:54:05 PM PDT by Lonesome in Massachussets (Doing the same thing and expecting different results is called software engineering.)
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To: Lonesome in Massachussets

With a few notable exceptions.

“Mikey” Weinstein, as an example.


37 posted on 08/12/2013 6:07:30 PM PDT by DuncanWaring (The Lord uses the good ones; the bad ones use the Lord.)
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To: DuncanWaring

I was speaking only from personal experience.


38 posted on 08/13/2013 2:49:06 AM PDT by Lonesome in Massachussets (Doing the same thing and expecting different results is called software engineering.)
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To: SunkenCiv; Renfield

At least they admit CO2 has not been driving the cycles. I’ve actually had alarmists argue that with me despite the fact the ice core data clearly show CO2 levels are a lagging factor.


39 posted on 08/13/2013 2:03:03 PM PDT by colorado tanker
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To: CPOSharky; SunkenCiv; All

But let’s not forget the probable North American boloid(s) around 13,000 years ago that may have caused the Younger Dryas. I suspect there are no simple or single answers. SC, time to post the Firestone et al book.


40 posted on 08/15/2013 11:31:50 PM PDT by gleeaikin
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