Effect of the earth's albedo on the ionospheric D layer

An aircraft carrying an ionospheric sounder traversed the boundaries of extended cloud cover near Los Angeles five times on July 18, 1967. Amplitudes of ionospheric E-layer echoes at 3 MHz were received and recorded on magnetic tape, and median values were determined in 1-minute intervals. Although these values scattered over ±3 decibels, the average median was lower, by 2.1 decibels, when the aircraft was over cloud cover than when the aircraft was over a cloud-free area. The results suggest that an enhancement of the flux of visible light due to the reflecting cloud cover (estimated albedo 40%) changed the D-layer chemistry in such a way that the electron density increased, resulting in a (6 ± 3)% increase of two-way non-deviative absorption.