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The glacial era...


Externet
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Repeatedly see illustrations on how extensive the ice age was thousands of years ago, covering to about 45-50 lat.N and beyond.    But never see the same depicted for southern latitudes.  How was the equatorial climate and temperature then ?  

And the equatorial flora + fauna did adapt and evolved in such 'short' amount of time to now tropical temperatures ?  Or was the temperature gradient such brutal from the icy edges to equator ?

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1 hour ago, Externet said:

Repeatedly see illustrations on how extensive the ice age was thousands of years ago, covering to about 45-50 lat.N and beyond.    But never see the same depicted for southern latitudes.  How was the equatorial climate and temperature then ?  

And the equatorial flora + fauna did adapt and evolved in such 'short' amount of time to now tropical temperatures ?  Or was the temperature gradient such brutal from the icy edges to equator ?

There is almost no land higher than 45 deg south of the equator, apart from Antarctica. Just the tip of S America. 

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And it might be more severe if there were lots of lands at higher southern hemisphere latitudes, due to earth perihelion being in early January.  That means N hemisphere winters are somewhat softened by greater solar proximity.  And S hemisphere subject to more extreme summers and winters, in terms of the insolation factor.  (Mercifully this is offset by the prevalence of ocean down under)

 

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Bear in mind that Antarctica has been sat in splendid isolation under some degree of permanent ice sheets since at least the Eocene-Oligocene boundary some 35 million years ago.

Simply a less dramatically eventful story than the relatively recent ebbs and flows of the Northern ice sheets. The major differences seem to stem mainly from one pole being covered by a continental land mass (very stable) and the other by an ocean. 

Edited by sethoflagos
small clarification
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5 hours ago, Externet said:

Repeatedly see illustrations on how extensive the ice age was thousands of years ago, covering to about 45-50 lat.N and beyond.    But never see the same depicted for southern latitudes.  How was the equatorial climate and temperature then ?  

And the equatorial flora + fauna did adapt and evolved in such 'short' amount of time to now tropical temperatures ?  Or was the temperature gradient such brutal from the icy edges to equator ?

At last someone wants to discuss some actual
Science.  +1

 

What has been said is true you have to go back to the permo-cretaceous period for the continental configurations to have been clustered around the south Pole.

We have a lot yet to discover but the story so far is that there have been at least four great periods of glaciation (geologists talk about glaciation, reporters talk about ice ages), thoughout history.

These have been separated by periods of little or no glaciation, for isntacne during the Jurassic period.

During these glaciation periods there have also been advances and retreats of the glaciers.

Here are a series of diagrams that help conflate glaciation with continental configuration and geological timescale.

Starting with charts of the timescales.

The Quaternary cenozoic 'iceage' corresponds to the iceage in the OP.

ice6.thumb.jpg.6d596e6b105ac9de813086150866ea04.jpgice1.jpg.be02388c02b487548547aa9c2ebd9367.jpgice2.jpg.fd31915b06438562c402ca960358d53c.jpgice3.jpg.146382b887334af3dba2b90e47de4d86.jpgice4.jpg.0c2b144b0d703e76562e863f497462bc.jpgice5.jpg.9091b662b74c2796447dd95ce733c271.jpg

 

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