Propagation at 36,000 MC in the Los Angeles basin

Fading characteristics at 36 kmc over a line-of-sight path in the Los Angeles basin have been shown to be closely correlated with meteorological conditions, particularly with the relatively persistent, low-level temperature inversion of the area. No positive evidence of the influence of atmospheric pollutants has been found, but it has been shown that suitably located microwave paths can be of value for locating and monitoring temperature inversions when they are accompanied by sufficient variation in water-vapor content. The relation of diurnal variations in propagation characteristics to diurnal variations in the temperature inversion and in atmospheric turbulence indicate that the refraction mechanism is the predominant one in causing the observed large fading amplitudes. The view is further strengthened by the relatively noncritical relation of fading to the proximity of the inversion layer.