Wednesday, April 11, 2007

What if CO2 Can’t Increase Warming?

With Wisconsin experiencing record snowfall totals for this date in April, it seems like another good opportunity for more evidence the theory of dangerous man-made global warming is simply false. H/T to the commenter at Small Dead Animals for bringing physics back into the discussion. Increasing carbon dioxide in the air does not have any additional effect on air temperature.

Why? Lars Kamél, from the Department of Astronomy and Space Physics at the University of Uppsala, writes that: "The main reason why CO2 can only have a small impact on the climate of the world is called saturation. This is a phenomenon well known from theory and observations of spectral lines in stellar atmospheres. An atom or a molecule does not absorb light and other electromagnetic radiation at all wavelengths. It only absorbs in narrow regions in the electromagnetic spectrum. Every atom or molecule has its own characteristic sequence of spectral lines.

"Carbon dioxide in the Earth's atmosphere has exactly one important spectral line in the infrared part of the spectrum. This line is clearly saturated. If you increase the number of CO2 molecules in the atmosphere, not much will happen. The amount of infrared radiation, that is, heat, that will be absorbed changes only by a minimal and insignificant amount."

"Since CO2 absorbs all radiation in this band it absorbs and reradiates 8.4% of the total energy within 200 meters of the surface. Adding more CO2 does not increase this effect because it is at its maximum. Using the absorptivity function (Beer's Law) for a gas, CO2 would only begin to lose this impact if CO2 concentration dropped below a few parts per million. It has been above 200 ppm for over a million years according to geophysicists. Thus I claim the heat retention as a percentage of Earth's total radiation by CO2 is constant".

What we have here is a double-whammy. Not only is the man-made CO2 vapour concentration contribution to the green-house gas effect minuscule, changes in concentration don't have significant effect either.

When you do the math the numbers show there is very little carbon dioxide in the air in the first place, but even increasing CO2 to say 400 parts per million will have no effect because the wavelength of infrared that can be absorbed will have already been absorbed. In other words, you can warm things up by adding more energy but only the sun can do that. Once you mop up the energy the sun spills on the planet each day, having extra paper towels around doesn’t do anything.