Open AccessRAPID PERIODIC FLUCTUATIONS OF THE GEOMAGNETIC FIELD. I
Author(s) -
Holmberg E. R. R.
Publication year - 1953
Publication title -
geophysical journal international
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.302
H-Index - 168
eISSN - 1365-246X
pISSN - 0956-540X
DOI - 10.1111/j.1365-246x.1953.tb03033.x
Subject(s) - earth's magnetic field , quiet , geophysics , ionosphere , daytime , physics , flux (metallurgy) , geology , geomagnetic secular variation , field (mathematics) , geodesy , magnetic field , geomagnetic storm , atmospheric sciences , astronomy , mathematics , materials science , quantum mechanics , metallurgy , pure mathematics
Summary Part I of this paper contains the presentation of a new analysis of observational material, mainly from Eskdalemuir, and describes some unexpected properties of geomagnetic fluctuations. The chief of these are ( a ) that there is a change of type at sunset from a continuous flux of disturbance to a comparative quiet punctuated by short damped wave trains, and ( b ) that the daytime fluctuations have a spectrum with definite fine structure. Part II is a discussion of the probable origin of geomagnetic pulsations. By comparing the characteristics found in Part I with those reported by previous observers it is concluded that the effects have a common cause, and very general arguments are then put forward to show that their origin is terrestrial. A survey of possible physical models points, after elimination, to a magneto‐hydrodynamical resonance in one or more of the ionospheric layers.