In the Aug. 9 editorial, you say that global warming ranks close to zero on most Americans’ list of concerns. This may simply indicate good sense. Although global warming may exist, there is no real consensus that anthropogenic sources of carbon dioxide are responsible for the slight observed increase in global temperatures.
Carbon dioxide is a minor greenhouse gas that contributes only about 3 percent to the greenhouse effect, and anthropogenic sources represent some 3 to 4 percent of carbon dioxide emissions, the rest being from natural sources. The major greenhouse gas is water vapor. It has been estimated that if all the carbon dioxide in the atmosphere were to magically vanish, it would lead to a 1-degree Celsius decrease in global temperatures. Given the complexity of modeling the Earth’s climate, and the very small effect that anthropogenic sources of carbon dioxide can be expected to have, the predictions of the climate models would have to be far more accurate than even their most vociferous proponents claim, in order to justify their use as a basis for public policy.
What is certain in all this is that the science is nowhere near the point of being able to say that anthropogenic sources of carbon dioxide are responsible for global warming. The only scientifically justifiable action at this point is continued monitoring and research.
