RE: Climate Changes Mid-late Dinosaur era.

["Edels" <edels@email.msn.com>]

My understanding is that several things were occurring:

1)      This was not a truly homogeneous climate, but one with a higher AVERAGE
temperature than today's.
2)      The poles DID reach freezing and below in winter, but not as low as in
modern times - and not for as long a period of time each year.
3)      The majority (70%?) of the planet was as warm and (usually) humid as the
tropic zones of today.
4)      A consistent warm equatorial current that was only occasionally
interrupted by continental drift.
5)      High sea levels (with corresponding reductions of land) [This is a
generalization - I know that the levels changed several times throughout the
Mesozoic - especially at the end].
6)      Due to the increased humidity and temperature, plant life was very
abundant.  This also led to increased CO2 and this helped keep the
temperature high (and the herbivores well fed!).
7)      There are (now disputed) reports of higher O2 content during several
periods of the Mesozoic, particularly near the KT boundary.  (Based on
trapped atmospheric gases in amber).

Note that #4 is probably the most important in maintaining a nearly
homogeneous warmer climate, with #6 possibly next most important.

Hope this helps,

Allan Edels


-----Original Message-----
From: owner-dinosaur@usc.edu [mailto:owner-dinosaur@usc.edu]On Behalf Of
Daniel Bensen
Sent: Tuesday, July 03, 2001 6:36 PM
To: david.marjanovic@gmx.at
Cc: The Dinosaur Mailing List
Subject: Re: Climate Changes Mid-late Dinosaur era.


>>
Global temperatures must have been quite warm indeed, and the temperature
differences between latitudes very low. Palm trees grew on Spitsbergen aka
Svalbard, champsosaurs thrived on Bylot island in the northern Canadian
Arctic (Nunavut meanwhile)...<<

Hey!  How does that work?  A homogeneous global climate?  I thought that was
only in science fiction.  What could explain such a thing?

Dan