The environmentalists have decided that global warming skeptics are mentally ill and are having a conference to discuss this theory. Dr. Sanity has a long post about this describing all sorts of mental problems, some of which the environmentalists themselves must be suffering. The environmentalists would no doubt brand me as one of the mentally ill, and would nominate me incarceration. (Like most of the left, they don't believe in freedom of speech for people that they don't agree with.) Here is a letter to the editor that I wrote.

Issues with the Catastrophic Global Warming Hypothesis

The Catastrophic Global Warming Hypothesis is based on the fact that greenhouse gases absorb infrared radiation. Emphasis has been placed on carbon dioxide even though water vapor is by far the most significant greenhouse gas in the atmosphere, partially because of cloud formations that reflect solar energy. An increase in carbon dioxide in the atmosphere will cause a temperature increase. By the Clausius-Clapeyron equation, the amount of water vapor that can be contained in the air goes up exponentially with temperature. The hypothesis is that relative humidity of the air will remain constant, so there will be an increase in the water vapor in the air, and this will cause a further increase in temperature, which will cause an even further increase in atmospheric temperature. This is called a positive feedback. If it further assumed that cloud cover does not change, then temperature will continue to spiral upward. Based on this, it is then assumed that carbon dioxide in the atmosphere is the primary driver of atmospheric temperature. Some object to this based on historical records that seem to imply that carbon dioxide levels have been an order of magnitude higher than at present, and the temperature obviously did not spiral upward.

The basis for projections that show much higher temperatures are General Circulation Models. These models use physical principles such as the Navier-Stokes equations to model the atmosphere with grid nodes with lateral dimensions of around 100 miles with smaller, variable heights. The resulting equations are solved using finite difference methods. The models do not do a good job of predicting humidity at higher altitudes, and cloud cover. Everyone knows that low level clouds have a huge impact on temperature, and that humidity varies widely both spatially and temporally. The fact that the GCMs essentially use assumed values for high altitude humidity and low level clouds casts severe doubt on the GCM projected temperatures. One difference in the GCMs and weather prediction models is that the latter have initial conditions reset frequently so errors are cancelled out, while whatever errors there are in the GCMs accumulate over projections made for the next 100 years. Recent balloon based radiosonde data indicates that upper atmosphere relative humidity actually declines as temperature increase. This is not surprising since GCM projections are not coming true either. As Roger Revelle, the godfather of the global warming hypothesis said, just before Al Gore threw him under the bus, a lot of research and data is needed before enacting public policy to reduce carbon dioxide emissions.