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klimatos
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- 36
I am a retired climatologist, not a physicist. I am seeking the help of physicists to resolve a matter that has always puzzled me. I shall try to list my reasoning in what appears to me to be a logical order. I will number my statements so that you may isolate my errors more easily. 1. When water vapor in the free atmosphere condenses into either water or ice, the temperature of the remaining gaseous atmosphere increases. 2. This increase in the temperature of the remaining gaseous phase is usually explained as a consequence of the “release” of latent heat (enthalpy of condensation) into the gaseous phase. 3. The mechanism of this transfer of thermal energy from the condensate to the remaining air remains obscure. Is it radiation, conduction, or mass transfer? 4. Mass transfer would seem to be out, since the mass transfer is occurring in the opposite direction—from the gaseous phase to the condensate phase. 5. Conduction would seem to be a poor choice, since the atmosphere is a notoriously poor conductor of thermal energy. 6. If the transfer is via radiation, is there an equivalent burst of radiation from the condensate during the process of condensation? 7. Or is it possible that this temperature increase does not represent a gain in thermal energy by the remaining atmosphere at all, but represents what might be termed a “statistical anomaly”? 8. I have always assumed that when a water surface vaporizes, the water molecules with the highest kinetic energy of translation normal to and away from the surface have the highest probability of escaping the various attractive forces of the liquid and becoming vapor molecules. 9. The selective nature of this process accounts for the fact that vaporization causes a mean energy loss (enthalpy of vaporization) in the vaporizing phase, thus reducing its temperature. 10. Because of the nature of the kinetic energy distribution curve, most of the molecules in “capture” proximity to a condensing surface will have very low kinetic energies of translation. 11. By selectively removing low KET molecules from the ambient air, the mean of the remaining molecular KETs is increased, resulting in an increase in temperature but a decrease in thermal energy content. 12. If true, this would have a significant impact on global heat budget studies. 13. If true, of course. That’s the sticker. 14. Where am I going wrong?