The ionosphere at Huancayo, Peru, October, November, and December, 1938

Abstract

This report on ionospheric conditions is in continuation of those published in preceding issues of this Journal submitting results of continuous multifrequency ionospheric recordings at the Huancayo Magnetic Observatory, Department of Terrestrial Magnetism, Carnegie Institution of Washington. The current data for the quarter October to December, 1938, are obtained from recordings for each hour of the day and for every day of the month except for short intervals necessary for maintenance of the equipment.Table 1 contains mean hourly values of virtual height, critical frequency, and lowest frequency received, for the last quarter of 1938. Figure 1 presents the data of Table 1 in graphical form. The following general discussion of characteristics is pertinent: (1) F‐region—Virtual heights during the daylight hours show little difference for October and November. Daytime heights for December were generally greater than for the preceding two months. The maximum heights for each month were recorded during the post‐sunset “hump.” The average maximum amplitudes for October and November are about the same but the amplitude of the December peak is somewhat less than the others. Also notable is the fact that the crests occurred at 19h, 20h, and 21h for October, November, and December, respectively.