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Volume 57 Supplement 12

Special Issue: Modelling the Earth’s Magnetic Field: the 10th Generation IGRF

Magnetic field modelling from scalar-only data: Resolving the Backus effect with the equatorial electrojet

Earth, Planets and Space volume 57, pages 1203–1209 (2005)Cite this article

Abstract

It is well known that models of the global geomagnetic field constructed from only measurements of the field intensity suffer from large errors arising from the Backus or perpendicular error effect. Knowledge of the location of the magnetic dip equator is in principal sufficient to eliminate this error. We investigate constraining the location of the dip equator using observations of the equatorial electrojet in intensity measurements made from the CHAMP satellite. While the models generated are inferior compared with models obtained from oriented three-component vector data, they may be of sufficient quality to allow construction of future global geomagnetic reference models in the absence of vector data.

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Author notes

  1. M. A. James

    Present address: School of Earth & Environment, University of Leeds, Leeds, LS2 9JT, UK

Authors and Affiliations

  1. Department of Earth and Ocean Sciences, University of Liverpool, 4, Brownlow St., Liverpool, L69 3GP, UK

    R. Holme & M. A. James

  2. GeoForschungsZentrum Potsdam, Telegrafenberg, D-14473, Potsdam, Germany

    H. Lühr

Authors
  1. R. Holme
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  2. M. A. James
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  3. H. Lühr
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Corresponding author

Correspondence to R. Holme.

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Holme, R., James, M.A. & Lühr, H. Magnetic field modelling from scalar-only data: Resolving the Backus effect with the equatorial electrojet. Earth Planet Sp 57, 1203–1209 (2005). https://doi.org/10.1186/BF03351905

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  • DOI: https://doi.org/10.1186/BF03351905

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