ANOMALOUS SHORT-WAVE ABSORPTION AND ATMOSPHERIC TIDES

Recent studies suggest that either clouds or water vapor in clear air absorb significantly more solar radiation (roughly 25 W m(-2) averaged globally) than previously thought. It is interesting, in this connect ion, that solar diurnal surface pressure tides, which are forced prima rily by insolation absorbed in the troposphere, are significantly unde restimated in current calculations. In this paper it is shown that inc reased absorption of the above magnitude results in sizable increases in the migrating diurnal surface pressure tide computed from classical tidal theory. Depending on how this extra forcing is distributed in t he troposphere, the annually averaged peak tide increases by 150 to 25 0 mu b when the anomalous absorption is considered, resulting in much better agreement with observations.