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Re: DINOSAUR digest 1201
> "James R. Cunningham" <firstname.lastname@example.org> wrote:
> >>>the oxygen content of the somewhat more dense
> atmosphere was about 25%, which is about 25% higher than now, that it
> was already falling toward the present level, and had been doing so
> for some time.>>>
> I understand the oxygen content of the atmosphere at present to be
> about 21%.
> If the O2 content of the Cretaceous were 25% (and amber studies are
> highly questionable in this regard),
> it is still no 25% higher than
> what we have now; it is about 4% higher.
'Fraid not. 0.25/0.209 = 1.196 or 19.6% higherI should have done the
arithmetic rather than saying 'about'. Dudley's graph shows the peak
early in the Tertiary at 26%, which would be 0.26/0.209 = 1.244 or 24.4 %
higher. The increase in partial pressure is what counts. I still should
have done the arithmetic.
> I think.
> John C. McLoughlin
> Taos, New Mexico