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A method for the interpretation of three-dimensional equatorial GDV fields

Earth, Planets and Space volume 50, pages141–151(1998)Cite this article

Abstract

The equatorial GDV fields have been widely measured in North-South magnetometer chains and the data so obtained interpreted by assuming that these variations are bi-dimensional. This hypothesis limits its application to the inference of the noon amplitude of the ionospheric current and to the case on which the suspected local Earth’s structure does not have discontinuities running along the direction normal to that of the electrojet current vector. In this work we develop a method to interpret three-dimensional GDV fields, based on the Riesz and in the Fourier integral transforms. This method consists in a numerical code that allows to separate, in real time, any threedimensional low frequency field, and a system equations to infer the ionospheric current system at daylight times and to predict the field induced from the external GDV field in a layered Earth’s model. We discuss the application of the method to data obtained in North-South magnetometer chains, and, by analyzing a particular case—data from the Indian geomagnetic observatories—we illustrate how the method increases the amount of information that may be obtained from these data.

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Affiliations

  1. Laboratorio de Geofisica, Departamento de Fisica, Universidad de Buenos Aires, Ciudad Universitaria Pabellón I, 1428, Buenos Aires, Argentina

    Silvia Duhau & Ernesto A. Martínez

Authors
  1. Silvia Duhau
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  2. Ernesto A. Martínez
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Correspondence to Silvia Duhau.

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Duhau, S., Martínez, E.A. A method for the interpretation of three-dimensional equatorial GDV fields. Earth Planet Sp 50, 141–151 (1998). https://doi.org/10.1186/BF03352095

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Keywords

  • Tectonic Feature
  • Geomagnetic Variation
  • Equatorial Electrojet
  • Equatorial Latitude
  • Spherical Harmonic Analysis