RE: Op-Ed LA Times: Oil decline

Speaking of the greenhouse effect one should keep things in historical
perspective

Today the earth has about 400 ppm. Below are the ppms for CO2 for ancient
periods.

                        P(CO2)
Miocene Pakistan <700
Miocene E. Africa <400
Eocene Wyoming <600
L. Cretaceous Texas 2500-3300
               Spain 1600-2600
U. Triassic/
l. Jurassic New Haven 2000-3000
            New Haven 2500-4200
            Fundy Rift 3000-6000
Thure E. Cerling, "Carbon Dioxide in the Atmosphere: Evidence from Cenozoic
and
Mesozoic Paleosols," American Journal of Science, 291(1991):377-400, p. 394

It is true, that the sun was weaker in the past than today so we don't want
to go back to 6000 ppm, but everyone freaking out about going from 300-400
ppm in my lifetime is a bit over the top. That rate of increase can not and
will not be sustained long enough to put the earth into runaway greenhouse.
Received on Mon Feb 16 21:21:45 2004