مرکز منطقه ای اطلاع رساني علوم و فناوري - Regularities in the behavior of regions E and F of the ionosphere

Abstract :

This paper describes recent work by Ratcliffe on the regularities in the F2 region of the ionosphere, the results of which are in process of publication in the Journal of Geophysical Research, as well as a study of the phase path of echoes from Region E. The regularities in the behavior of the F2 layer are shown by using a simple method for analyzing routine (h\´,f) records which is similar to the graphical method of Booker and Seaton. Records from Watheroo, Huancayo, and College have been analyzed to determine the total number, ( $n$ ), of electrons below the level of maximum electron density in a column of unit cross section in the F2 region. This analysis shows that $n$ is closely related to the sun\´s zenith angle $x$ whereas the maximum electron density $N_{m}$ is not simply related to $x$ . The well-known anomalies when $N_{m}$ is studied as a function of time of day, time of year, and geographical position all seem to disappear when n is studied instead of $N_{m}$ . An anomaly observed at Huancayo is discussed and a relation between thickness and height of the F2 layer which may be of use in ionospheric forecasting is described. The results of three years\´ observations of the phase of echoes of about 2 mc per second in frequency from Region E are described. These show that the phase height of the region varies qualitatively, but not quantitatively, as would be expected for a simple Chapman region. The effects of fadeouts in increasing the absorption and also the phase heights for echoes from the region are described and measurements are given of the velocities of movement of clouds of ionization in the lower part of the E layer.