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An Analysis of the Lower Tropospheric Refractivity Bias by Heuristic Sliding Spectral Methods

  • Georg Beyerle
  • Jens Wickert
  • Torsten Schmidt
  • Rolf König
  • Christoph Reigber
Chapter

Summary

The canonical transform (CT) and full spectrum inversion (FSI) method together with their heuristic sliding spectral modifications are validated using end-to-end simulation data and one week of CHAMP observations. In general, we observe a pronounced correlation between small refractivity biases and enhanced penetration altitudes. Processing of simulated occultation data shows that the heuristic methods exhibit smaller retrieval errors vindicating the assertion that the sliding spectral approaches react less sensitive to receiver tracking errors. The corresponding mean retrievals errors found in the CHAMP data analysis, however, are consistent within 0.5%; differences are observed with respect to penetration altitudes and the retrieval errors' standard deviations.

Key words

Remote sensing GPS radio occultation canonical transform full spectrum inversion refractivity bias 

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Copyright information

© Springer-Verlag Berlin Heidelberg 2005

Authors and Affiliations

  • Georg Beyerle
    • 1
  • Jens Wickert
    • 1
  • Torsten Schmidt
    • 1
  • Rolf König
    • 1
  • Christoph Reigber
    • 1
  1. 1.Dept. 1: Geodesy and Remote SensingGeoForschungsZentrum Potsdam (GFZ)PotsdamGermany

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