"bill" wrote in message
oups.com...

Rand Simberg wrote:
On 16 Mar 2006 08:50:26 -0800, in a place far, far away, "bill"
made the phosphor on my monitor glow in
such a way as to indicate that:

"George" wrote in message

He also assumes that the environment in which we all live could
sustain
such levels. I don't think there is any precedent for that
assumption.

I don't think plants will complain.

How do you know? The planet has never sustained those levels.

800 ppm?

800 ppm will easily desertify the planet and melt all the ice.

increased temperature accelerates the evaporation precipitation
cycle, really, you are looking at more tropical type climates and less
desert.

Not to mention the fact that it would probably accelerate plant growth
rates (and in fact such acceleration would prevent the levels from
ever getting that high).

Valid point. I read somewhere that the equalization point is
around 600 ppm. Still not a good number though.
Another interesting poing is that I keep seeing people whine about
methane. They say that it is something stupid like 40x as potent a
ghg. Methane in the atmosphere has a 5 year half-life. so in order to
keep the levels high, you have to continually release.

Methane has a shorter lifespan in the atmosphere, but is more potent at
retaining heat in the atmosphere than is CO2. In addition, it breaks down
to CO2, and so increases the CO2 levels as well.

George