Quote Originally Posted by Zer0th View Post
@shortround: I'm not convinced you're interpreting those links correctly. For instance, as I read it, the first link says the isotopic assumptions may be dodgy because the determined 50C water temp is biologically unrealistic. Also, 350x CO2... when was that?

The general understanding, I believe, is that during the time of life on land, CO2 maxed at ~7,000ppm, ~20x that of recent times. The global max average ~24C, the global min average ~12C, as compared with now: ~14C. Ala...
http://i28.tinypic.com/288ytj7.jpg

With extra resolution...
http://biocab.org/Geological_Timescale.jpg
In several periods when the poles had reached 23C this would have needed extreme conditions ( albeit short lived) at the equator. The amount of energy needed to transmit that kind of water vapor over such distance and produce an ice free environment had to be temperature induced. I wouldn't at all be surprised if 50C was reached.

As for CO2 counts, we know the Siberian traps produced some of the largest flood basalts ever in earth history, estimates are from 1 to 4 million cubic meters of material, ( Iceland produced 12km and altered global temperature) sealing the lower atmosphere in a shroud of gas and dust, and probably brought about an extinction event unparalleled in geologic times. So the numbers are quite possible over a short period, and better known as spikes.

The charts and graphs we have today are based on long term periods and averages, and at best can be interpreted with a good margin of + - effects, and as data becomes more abundant, this will eventually narrow down exact times and dates.

I believe oceanic evaporation to be the key workings in climate balance, even in the midst of geological upheaval. So looking back at what has transpired in previous times, we have never experienced anything on a scale of these events, and yet the world has cleaned up after itself in a manor we have yet to understand.

As I have repeated several times, we have not yet reached the end of this current interglacial period, and to speculate what little effect we have as humans seems a bit futile in the face of previous cataclysm's, and the earths astounding ability to deal with them.