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Author Topic:   How do scientists explain the cause of the Ice Age(s)?
Jeff Davis
Junior Member (Idle past 4918 days)
Posts: 29
Joined: 09-05-2010


Message 40 of 96 (581194)
09-14-2010 12:14 PM
Reply to: Message 1 by jasonkthompson
02-25-2010 6:15 PM


Hello,
These huge threads are difficult to catch up on, so I apologize if I repeat anything.
First of all, we are still in an ice age. As long as there are continental glaciers on the planet, we are in an ice age. We are merely in the warming phase. Global warming has slightly altered the cycle a bit, but the cooling phase will come nonetheless. By the way, the massive Laurentide continental glacier that covered Canada and the northern parts of the U.S. is still around. It is in the Baffin Islands. We know this because the rock grooves and scratches (striations) lead directly to this particular ice sheet. It is no longer considered a glacier because it is not moving, but evidence suggests it will again.
I would like also to address the question about colder temperatures producing less precipitation. If this were the case, then why do we have devastating snowstorms in below freezing temperatures? The answer is (sorry for the long-winded answer, but its necessary), yes, colder air does decrease the rate of evaporation relative to condensation (reason for cloud formation leading to precipitation), but one must look at weather systems with respect to density and pressure differentials. The greater the difference in density between two airmasses, the greater the pressure difference. This can cause an extremely powerful moisture pump as long as there is a moisture source - the oceans. Well, we are called the water planet for a reason. Also, we need a power source for production of precipitation, the Sun. Since the Sun produces nearly 50 billion kilowatts of energy to the Earth per day, the energy source is here to stay.
There is another correlation in connection to continental glacial advances than just the Milankovitch cycles. From a paleontology perspective, when we look at every ice age throughout Earth history, we see that a continent is located at one of the poles (especially the South Pole). The reason why this is important is because it creates extreme cold temperatures. Frozen oceans at the poles do not cool down as much, thus, will not produce the pressure differentials needed to sustain a cooling phase. Take for example the reason why the coldest temperatures on the planet are at the South Pole and not the North Pole. The North Pole presently has no continent underneath it.
Best,
Edited by Jeff Davis, : No reason given.
Edited by Jeff Davis, : No reason given.

This message is a reply to:
 Message 1 by jasonkthompson, posted 02-25-2010 6:15 PM jasonkthompson has not replied

Replies to this message:
 Message 41 by Taq, posted 09-14-2010 3:20 PM Jeff Davis has replied
 Message 42 by Dr Adequate, posted 09-14-2010 4:11 PM Jeff Davis has replied

  
Jeff Davis
Junior Member (Idle past 4918 days)
Posts: 29
Joined: 09-05-2010


Message 43 of 96 (581282)
09-14-2010 9:41 PM
Reply to: Message 42 by Dr Adequate
09-14-2010 4:11 PM


I believe you are missing my point. The ice sheet is not in motion at all, so it is not considered a glacier.

This message is a reply to:
 Message 42 by Dr Adequate, posted 09-14-2010 4:11 PM Dr Adequate has replied

Replies to this message:
 Message 45 by Dr Adequate, posted 09-14-2010 10:55 PM Jeff Davis has replied

  
Jeff Davis
Junior Member (Idle past 4918 days)
Posts: 29
Joined: 09-05-2010


Message 44 of 96 (581283)
09-14-2010 9:48 PM
Reply to: Message 41 by Taq
09-14-2010 3:20 PM


Taq,
I have to disagree. What you are seeing on the chart you posted is a warming and cooling cycle. The fact that it is a cycle means it is all connected. There has been a causal relationship for 2.2 million years and it seems not to be done. Prior to this, there was no cycle at all (accept for a few times in the ancienct past). Your argument seems to be: ige age, no ice age, ice age, no ice age, ice age, etc. Can you not see that a cooling phase or warming phase, or interglacial period, best conforms to the evidence?
best,
Edited by Jeff Davis, : No reason given.

This message is a reply to:
 Message 41 by Taq, posted 09-14-2010 3:20 PM Taq has not replied

  
Jeff Davis
Junior Member (Idle past 4918 days)
Posts: 29
Joined: 09-05-2010


Message 46 of 96 (581377)
09-15-2010 11:24 AM
Reply to: Message 45 by Dr Adequate
09-14-2010 10:55 PM


Now, that's a bet I'd love to lose. From a pilsner to a stout. It's on me!

This message is a reply to:
 Message 45 by Dr Adequate, posted 09-14-2010 10:55 PM Dr Adequate has not replied

  
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