Two Anomalies in the Ionosphere

Abstract

DURING the War, many new ionospheric stations were instituted in different parts of the world to serve the operational requirements of the Allied Forces. As a result, there have become available, for the first time, sufficient data to provide a rough general morphological picture of the F₂ layer of the ionosphere. A study of these data has disclosed the remarkable result that, although ionospheric events in the E and F₁ layers are similarly reproduced at the same local time on the same day at all locations on a line of constant geographic latitude, the same is by no means the case for the F₂ layer. It has also been confirmed, as was suspected earlier, that under conditions of symmetrical solar illumination, an asymmetry of ionization exists for certain station on the same longitude and situated at equal latitudes north and south of the equator.