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Time-Variable Gravity Field and Global Deformation of the Earth

  • Jürgen Kusche

The analysis of the Earth’s time-variable gravity field, and its changing patterns of deformation plays an important role in Earth system research. These two observables provide, for the first time, a direct measurement of the amount of mass that is redistributed at or near the surface of the Earth by oceanic and atmospheric circulation and through the hydrological cycle. In this chapter, we will first reconsider the relations between gravity and mass change. We will in particular discuss the role of the hypothetical surface mass change that is commonly used to facilitate the inversion of gravity change to density. Then, after a brief discussion of the elastic properties of the Earth, the relation between surface mass change and the three-dimensional deformation field is considered. Both types of observables are then discussed in the framework of inversion. None of our findings is entirely new, we merely aim at a systematic compilation and discuss some frequently made assumptions....

Keywords

Global Position System Gravity Change Love Number Spherical Harmonic Coefficient Superconducting Gravimeter 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  • Jürgen Kusche
    • 1
  1. 1.Astronomical, Physical and Mathematical Geodesy GroupBonn UniversityBonnGermany

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