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Journal of Geodesy

, Volume 85, Issue 9, pp 607–615 | Cite as

Assessing Greenland ice mass loss by means of point-mass modeling: a viable methodology

  • Oliver Baur
  • Nico Sneeuw
Original Article

Abstract

Greenland ice mass loss is one of the most serious phenomena of present-day global climate change. In this context, both the quantification of overall deglaciation rates and its spatial localization are highly significant. We have thoroughly investigated the technique of point-mass modeling in order to derive mass-balance patterns from GRACE (Gravity Recovery And Climate Experiment) gravimetry. The method infers mass variations on the Earth’s surface from gravitational signals at satellite altitude. In order to solve for point-mass changes, we applied least-squares adjustment. Due to downward continuation, numerical stabilization of the inversion process gains particular significance. We stabilized the ill-posed problem by Tikhonov regularization. Our simulation and real data experiments show that point-mass modeling provides both rational deglaciation rates and high-resolution spatial mass variation patterns.

Keywords

GRACE Satellite gravity Mass variation Least-squares adjustment Regularization 

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Copyright information

© Springer-Verlag 2011

Authors and Affiliations

  1. 1.Institute of GeodesyUniversity of StuttgartStuttgartGermany
  2. 2.Space Research InstituteAustrian Academy of SciencesGrazAustria

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