Open AccessInduced magnetic field of the equatorial electrojet at the surface of the Earth
Author(s) -
Bhattacharyya Archana
Publication year - 1981
Publication title -
geophysical journal of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.302
H-Index - 168
eISSN - 1365-246X
pISSN - 0016-8009
DOI - 10.1111/j.1365-246x.1981.tb06936.x
Subject(s) - electrojet , equatorial electrojet , geophysics , noon , electromagnetic induction , magnetic field , observable , physics , field (mathematics) , earth's magnetic field , geology , atmospheric sciences , mathematics , quantum mechanics , pure mathematics , electromagnetic coil
Summary. The northward component of the induced magnetic field due to the equatorial electrojet at the Earth's surface is calculated using a more realistic local time variaton of the external field due to the electrojet than is provided for by models of the electrojet currently used in induction calculations. It is seen that appreciable induction effects can be expected about an hour before local noon for the kind of local time variation considered. Our results are in qualitative agreement with direct observations of Earth currents in the equatorial region in Nigeria. At local times when observable induction effects are present, the magnetic field due to the electrojet is necessarily three‐dimensional; hence in order to obtain the internal part directly from the observed total field due to the electrojet at the Earth's surface, a three‐dimensional formulation is required.