From: Andrew Clough (aclough@mit.edu)
Date: Wed Jul 23 2003 - 21:03:04 MDT
At 01:06 PM 7/13/2003 -0700, you wrote:
>If one looks at the amount of carbon in the earth's
>atmosphere as a function of time, it is straight
>downhill, is it not? When the earth had a reducing
>atmosphere, there was all that methane and carbon
>dioxide. Plants came, generated oxygen, which broke
>down the methane, steadily depleted the CO2, converting
>it into coal and oil, carbon forms which are out of
>reach of the lifeforms that evolved here. Well, all
>of the lifeforms except humans.
>
>Without some means of restoring that carbon to the
>biosphere, it would have been curtains for all life
>on this planet. It would have gradually suffocated
>for lack of raw material, perhaps in the next billion
>years, steadily fading away with robust memories,
>like the Civil War soldier's reunion.
Actually, current geological thought says that its worse, but also better
than that. When a reduction in atmospheric CO2 progresses far enough, the
polar caps grow, and the increased albedo from them further cools the Earth
in a runaway process that ends with our planet becoming one big
snowball. This seems to have happened several times in the distant past,
put with massive death among photosynthesizers, the CO2 released from
volcanos (that's where inducted carbon eventually ends up) built up enough
to reverse the process. Luckily, the increased light from an expanding sun
(or the emergence of Gaia take your pick) seems to have prevented this from
happening in "recent" geological history.
Never attribute to malice what can be explained by stupidity..
-M.N. Plano
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