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  • Article
  • Open Access

Modelling of spatial-temporal changes of the geomagnetic field in Japan

Earth, Planets and Space201458:BF03351979

  • Received: 28 April 2005
  • Accepted: 2 June 2006
  • Published:


A geomagnetic regional model is constructed to provide a spatial-temporal variation of three orthogonal components (X, Y, Z) in Japan. In order to obtain a high temporal and spatial resolution, Natural Orthogonal Components (NOC) analysis and Spherical Cap Harmonic (SCH) analysis were employed to produce a spatial-temporal model based on the observed data from geomagnetic observatories and continuous geomagnetic stations. Using this model, we calculated the secular variation between 1999 and 2004 in Japan. The root mean square (RMS) scatter of the model is less than 3 nT, which indicates a good agreement between calculated and input data.

Key words

  • Geomagnetic regional model
  • spatial-temporal model
  • secular variation
  • Natural Orthogonal Components
  • Spherical Cap Harmonic