Cessna 310 wrote in :

http://www.clearlight.com/~mhieb/WVF.../ice_ages.html

My favorite quote from it:

"2. CO2 in our atmosphere has been increasing steadily for the last 18,000
years-- long before humans invented smokestacks ( Figure 1). Unless you
count campfires and intestinal gas, man played no role in the pre-
industrial increases."

This brings into question how much intestinal gas ancient man produced,
given he had no beer, that we know of....

Larry
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