A Comparison of Global Lithospheric Field Models Derived from Satellite Magnetic Data

  • Kumar Hemant
  • Stefan Maus

Summary

Satellite missions over more than three decades, have added immensely to our understanding of the geomagnetic field. Here, we give a comparison of the lithospheric field models, prepared by various workers from POGO, Magsat, Ørsted and CHAMP satellite data. Mapping the global lithospheric anomalies requires careful reductions which include the main field, its secular variation (SV) and corrections for the external magnetospheric and ionospheric contributions to the data recorded by satellite. The discrepancies between the various maps are mainly due to differences in the rigor with which the data is processed, in the selection of the magnetically quiet periods and in the algorithms used to estimate the spherical harmonic coefficients of scalar potential or the total intensity of the field. The models also strongly differ in how the magnetospheric and ionospheric contributions have been detected and eliminated in order to correct the equatorial, mid-latitude and polar latitude data. We plot the anomaly of the total intensity of the field at 450 km altitude (except ALP94 which is at 400 km).

Key words

Power spectra filtering lithospheric field models 

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Copyright information

© Springer-Verlag Berlin Heidelberg 2003

Authors and Affiliations

  • Kumar Hemant
    • 1
  • Stefan Maus
    • 1
  1. 1.Division 2.3GeoForschungsZentrumPotsdamGermany

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