Canopy theory questions
Bill Hamilton (hamilton@predator.cs.gmr.com)
Thu, 26 Feb 1998 15:51:05 -0500I have heard objections to the canopy theory that are based on the claim
that the environment under the canopy would be too hot to sustain life, but
I'm not very familiar with the arguments used to support this claim. I
suppose I really ought to get Glenn's CRSQ paper, but can you folks give me
a summary? I can think of two reasons why it would be too hot: 1) If all
the water in the oceans were in vapor form, the vapor pressure of water in
the atmosphere would be significantly (and that's an understatement) higher
than what we consider normal today. Higher vapor pressure requires higher
temperatures, so it would be necessary for the temp to be higher; 2) The
increased water vapor in the atmosphere would serve as a greenhouse gas
which would trap more of the sun's heat.
Some arguments seem to imply that the increased pressure itself would
increase the heat. Certainly if there was a time at which the vapor was
added to the atmosphere over a relatively short time, I suppose there would
be adiabatic compression which would cause a release of heat, and I suppose
the increased water vapor in the atmosphere, acting as an insulator would
restrict the dissipation of that heat. But that seems to require some
assumptions about how quickly the water vapor was dumped into the atmosphere.
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Bill Hamilton
Staff Research Engineer
Chassis and Vehicle Systems
GM R&D Center
Warren, MI