Minimum vertical scale sizes in the wind structure above 100 kilometers

Zimmerman [1964] has compared the small-scale wind structure that can be detected at high altitudes with the theoretical minimum structure sizes that can be attributed to freely propagating internal atmospheric gravity waves [Hines, 1960, henceforth paper I]. He found that the theoretical curve adequately represented the minimum observed sizes at altitudes up to 130 km, but that, at least for the ‘summer’ data, it fell substantially short of the observed sizes at higher altitudes. He was led to suggest a transition to some other limiting process which would yield minimum sizes proportional to the atmospheric scale height. While the discrepancy found by Zimmerman was in an acceptable direction in the sense that the observed minimum scale sizes were greater than the theoretical minimum scale sizes, a reexamination of the theoretical work seemed to be in order. It became apparent that I had made a computational or plotting error in the preparation of Figure 12 of paper 1, that this error would lead to an incorrect estimate of the theoretical minimum scale size at a height of 225 km, and that it had in fact led (through interpolation) to a faulty theoretical curve for all heights above about 110 km in Zimmerman's diagrams.