Characteristics of Radio Noise Power at Byrd Station, Antarctica
- A. H. Waynick
Published Online: 14 MAR 2013
Copyright © 1965 by the American Geophysical Union.
Geomagnetism and Aeronomy: Studies in the Ionosphere, Geomagnetism and Atmospheric Radio Noise
How to Cite
Herman, J. R. (1965) Characteristics of Radio Noise Power at Byrd Station, Antarctica, in Geomagnetism and Aeronomy: Studies in the Ionosphere, Geomagnetism and Atmospheric Radio Noise (ed A. H. Waynick), American Geophysical Union, Washington, D. C.. doi: 10.1029/AR004p0189
- Published Online: 14 MAR 2013
- Published Print: 1 JAN 1965
Print ISBN: 9780875901046
Online ISBN: 9781118664537
- Auroral zone absorption (AZA);
- Median noise power variations;
- National bureau of standards (NBS);
- Polar cap absorption (PCA);
- Thunderstorm activity
Atmospheric radio noise measured on the frequencies of 0.051, 0.113, 0.246, 0.545, 2.5, 5.0, 10, and 20 Mc/s at Byrd station, Antarctica, from March 1958 to December 1959, is investigated to establish diurnal, seasonal, and frequency variations. Since no thunderstorms occur at Byrd, the atmospheric noise is received only by ionospheric propagation modes from distant sources, such as the major active centers in Central Africa, the East Indies, and Central and South America. It is shown that the noise level is affected both by changes in world thunderstorm activity and by changes in propagation factors. In the high-frequency band the noise sources in Central and South America are the major contributors to the noise power measured at Byrd station.
A ‘noise index' is defined and used to select periods of anomalous absorption. Fourteen polar cap absorption (PCA) events are detected by the index, all of which have been previously reported on the basis of northern hemisphere observations. It is shown that the HF noise level at Byrd is severely depressed during PCA, especially on 5.0 and 10 Mc/s. The minimum noise level observed during PCA is used to establish the man-made noise level at Byrd, which is about 23 db lower than the level expected for a typical quiet receiving site as defined by the International Radio Consultative Committee (CCIR). Analysis of an auroral zone absorption event (October 22–31, 1958) indicates that the absorbing region must be situated between Byrd station and South America before the noise level is affected. Seventeen other auroral zone absorption events, eleven of which are associated with geomagnetic storms, have been detected by the noise index and are listed in the report.