Thread: Vapour trails
View Single Post
  #43  
Old December 15th 04, 11:17 PM
Newps
external usenet poster
 
Posts: n/a
Default



Dean Wilkinson wrote:
So, lets look at this factually...

In recent history, atmospheric CO2 levels have been at their lowest levels
in the entire history of the planet.


You have no way of knowing that. I can just see the caveman out there
with his CO2 test kit.....


It has been as low as about 150 ppm.
In recent history, it has been steadily climbing toward 300 ppm, presumably
due to human activity, but there has been a fair amount of volcanic activity
in recent years which also contributes large amounts of CO2.


It's a guess. We only have maybe 150 years of temp data and much less
years of other data. In the history of the planet that is zip.



Also, historical global temperature data shows that the earth has a
bi-stable average temperature (bouncing between 12C and 22C). The average
temperature of the earth is currently at the low bi-stable point, but
throughout most of the earths history, the temperature was at the high
bistable point. The last time that the earth had the current combination of
low CO2 and low average temperature was about 300 million years ago.


The earth has cooled and warmed constantly. Glaciers come and go.
Humans couldn't change that if they wanted.