A Comparison of Data Weighting Methods for the Combination of Satellite and Local Gravity Data

Conference paper
Part of the International Association of Geodesy Symposia book series (IAG SYMPOSIA, volume 127)


The combination of heterogeneous gravity data is among the most involved problems in gravity field modeling. With newly available gravity data from dedicated satellites, such as CHAMP, GRACE and GOCE, additional low-frequency information about the gravity field will be available. Local or regional data collected closer to the Earth’s surface allows the resolution of the medium to high frequency components of the gravity field. Although for applications, such as geoid determination, most of the power is contained in the lower frequencies, a geoid at the cm-level, which is required by oceanography and geodesy alike, will require a much wider spectrum than the one that can be resolved by satellite methods. To enhance and widen the gravity field spectrum, a data combination process is essential.

The comparison of data weighting methods for the spectral combination of satellite and local gravity data is the topic of the paper. The quality of each method is evaluated with respect to the requirements, inherent assumptions and errors. Based on the detailed characterization of the methods, the quasi-deterministic method seems to be the most promising for the combination of satellite and local gravity data.


Combination methods Gravity field modeling Satellite gravity missions Filters 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2004

Authors and Affiliations

  • M. Kern
    • 1
  1. 1.Department of Geomatics EngineeringThe University of CalgaryCalgaryCanada

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