Global warming

Among the multitude of facts and opinions in magazines, books, and on television, I have never seen an analysis of whether or not global warming will be self-limiting due to the effect of the Stefan-Boltzmann law (see also Wien's law). This law of blackbody radiation states that the energy, E, that is emitted by a body with temperature T is proportional to the fourth power of the temperature: E = σT4.

Since the average "in-radiation" from the sun at any given location and at the same time of the year is for all practical purposes a constant, any heating due to a greenhouse effect would be expected to reach a self-limiting equilibrium very quickly after only a very modest rise in temperature. The reason is that the "out-radiation" will overpower the greenhouse effect after a very small temperature rise because of the enormous countervailing effect of the Stefan-Boltzmann law.

Oswald R. Bergmann
Wilmington, Del.