Open AccessVariability of the ocean‐induced magnetic field predicted at sea surface and at satellite altitudes
Author(s) -
Glazman Roman E.,
Golubev Yury N.
Publication year - 2005
Publication title -
journal of geophysical research: oceans
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2005jc002926
Subject(s) - geophysics , satellite , magnetic field , magnetometer , geology , earth's magnetic field , field (mathematics) , geodesy , computational physics , physics , atmospheric sciences , mathematics , quantum mechanics , pure mathematics , astronomy
Spatial and temporal variability of the magnetic field component induced by ocean circulation is investigated on the basis of a standard thin‐shell approximation of electro‐ and magneto‐static equations. Well‐known difficulties of numerical solution of the governing equations are resolved by reducing the problem to an equation for the electric field potential, Φ, as opposed to a more conventional approach focused on the vertical jump, ψ, of the magnetic field potential across a combined ocean/marine‐sediment‐layer spherical shell. The present formulation permits using more realistic input data on ocean currents and ultimately yields much greater (by at least an order of magnitude) values of the magnetic field at sea surface than predicted in earlier studies. Such large values are comparable to, and in some cases exceed, magnetic field variations caused by lithospheric and ionospheric sources on monthly to interannual timescales. At the 400‐km altitude (of CHAMP satellite), the field attains 6 nT. The model predictions show favorable comparisons with some in situ measurements as well as with Challenging Minisatellite Payload (CHAMP) satellite magnetometer data.