Abnormal features of the F₂ region of the ionosphere at some southern high-latitude stations

Abstract

The paper describes some abnormal features of the F₂ layer at high-latitude stations in the southern hemisphere. The variation of the midday value of the critical frequency of the F₂ layer (ƒ₀F₂) with magnetic dip shows assymmetry between the northern and southern stations of the west (American) zone, but not of the east zone. The control by the earth's magnetic field is indicated in the latitudinal distribution of even the midnight values of ƒ₀F₂. The diurnal variation of ƒ₀F₂. at Port Lockroy shows abnormal minimum at midday and maximum at midnight during the summer months. These abnormal features of the F₂ layer at Port Lockroy are explained on the basis of the horizontal transport of ionization as guided by the earth's magnetic field.