Carbon Dioxide and Its Role In Global Warming

I'm repeating a previous post here because it is question that needs an answer. It is critical to the issue of global warming.
Peter

Wednesday, March 21, 2007

Scientific Help On Carbon Dioxide...Please
I need some help from a really sharp chemist or physicist. I read a letter and opinion in the Sunday Letters section of the "Dallas Morning News" on March 4, 2007 and it is really important to this whole issue of man-caused global warming.I'd like an informed opinion on what this person is saying, because if it is true, all the carbon dioxide (CO2) in the world is not going to cause global warming, and all of this talk about cutting CO2 emissions is just a waste of time and a humongous waste of money. Help me out here folks. Is this true or not? We need to know the truth. Here is the letter:
Peter

Carbon dioxide constant
Mike Hashimoto is a breath of fresh air. (Referring to a Dallas editor skeptical of global warming.) I did research on carbon dioxide infrared absorption about 10 years ago for Texas Instruments and Raytheon as a carbon dioxide detection project under contract to Carrier Corp.The importance of carbon dioxide to global heat retention can be determined by examining the atmospheric infrared absorption data reported on by the Environmental Research Institute of Michigan more than 50 years ago.Its data show that carbon dioxide absorbs 8 percent of the heat radiated by our planet, and that the absorption is complete in a path length of only 300 meters. Thus the overall heat retention of carbon dioxide is 8 percent.Since the heat absorption is complete for carbon dioxide in its absorption band, adding more carbon dioxide to the atmosphere does not increase its global heat retention effect. Carbon dioxide gives us a constant warming effect over a wide range of concentration, which now is about 380 parts carbon dioxide to one million parts of air. The point is that carbon dioxide's ""greenhouse effect" is constant and cannot increase with more carbon dioxide. It has been constant for millions of years.

Sebastian Borrello, Allen