Accession Number : AD0288236

Title :   DIURNAL VARIATION AND SOME OTHER CHARACTERISTICS OF EXTREMELY LOW FREQUENCY MAGNETIC FIELDS

Corporate Author : RHODE ISLAND UNIV KINGSTON

Personal Author(s) : POLK,C.

Report Date : 02 AUG 1962

Pagination or Media Count : 1

Abstract : Amplitude versus time records of 2-minute duration of North-South and East-West magnetic field variations in the 5 to 20 cps frequency range, and 24-hour records of 7.5 to 10 cps magnetic fields which were obtained over a period of several months are analyzed. It appears that the most prominent frequency of individual wave trains in thi frequency range is not constant, that some imperfect correlation exists between ELF noise and solar activity, and that 7.5 to 10.0 cps ELF intensity (recorded on an East-West coil) is normally higher during daylight hours than the corresponding ELF intensity recorded at night. The diurnal variation of ELF intensity averaged over a 75 day period between April and July 1962 closely resembles the diurnal variation of thunderstorm activity in the Western hemisphere, based upon data accumulated before 1960. (Author)

Descriptors :   *GEOMAGNETISM, DIURNAL VARIATIONS, EXTREMELY LOW FREQUENCY, INSTRUMENTATION, MEASUREMENT, PERIODIC VARIATIONS

Distribution Statement : APPROVED FOR PUBLIC RELEASE