Some Investigations of the Effect of Mountain wave on the Distribution of the Atmospheric Refractive Index

Abstract

The distribution of the atmospheric refractive index was observed repeatedly at elevations up to 3 Km over the course between Tokyo and Sendai. UHF propagation experiment was also conducted over the 310 Km land-path between Tokyo and Sendai. Considering the effect of mountain wave which was caused by the gently sloped mountain ridge near the midpoint of the course, meteorological interpretation was made on both the observed Nprofiles and the spatial distribution of *N2. The influence of the airflow across a mountain ridge on the variation of the UHF transmission loss, L, was also investigated by the use of the upper meteorological data. Correlation between the observed hourly median values of L and the relative values of the scattering cross section, a, estimated by the upper meteorological data is fairly good.