LATITUDINAL VARIATION OF MESOPAUSE HEIGHT INFERRED FROM ECLIPSE OBSERVATIONS,

Observations of the flattening of the earths shadow during lunar eclipses were used to compute the magnitude of a latitudinal height variation of the shadowproducing level. By means of a postulate that this level is associated with a temperature minimum in the earths upper atmosphere, a latitudinal variation is inferred for for the mesopause, with the equatorial height being about 25 km greater than the height over the poles. Further inferences led to the conclusion that a double mesopause may be a consistent feature, and that the separation distance between the two mesopause altitudes could vary from a maximum of about 30 km over the equator to zero over the poles. It was finally shown that these conclusions were not necessarily inconsistent with the sparse experimental data presently available. Author