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What Might GRACE Contribute to Studies of Post Glacial Rebound?

  • John Wahr
  • Isabella Velicogna
Part of the Space Sciences Series of ISSI book series (SSSI, volume 17)

Abstract

The NASA/DLR satellite gravity mission GRACE, launched in March, 2002, will map Ihe Earth’s gravity field at scales of a few hundred km and greater, every 30 days for five years. These data can be used to solve for time-variations in the gravity field with unprecedented accuracy and resolution. One of the many scientific problems that can be addressed with these time-variable gravity estimates, is post glacial rebound (PGR): the viscous adjustment of the solid Earth in response to the deglaciation of the Earth’s surface following the last ice age.

In this paper we examine the expected sensitivity of the GRACE measurements to the PGR signal, and explore the accuracy with which the PGR signal can be separated from other secular gravity signals. We do this by constructing synthetic GRACE data that include contributions from a PGR model as well as from a number of other geophysical processes, and then looking to see how well the PGR model can be recovered from those synthetic data. We conclude that the availability of GRACE data should result in improved estimates of the Earth’s viscosity profile.

Keywords

Satellite Laser Range Lower Mantle Uppermost Mantle Lithospheric Thickness Viscosity Profile 
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 Science+Business Media Dordrecht 2003

Authors and Affiliations

  • John Wahr
    • 1
    • 2
  • Isabella Velicogna
    • 1
    • 2
  1. 1.Department of Physics and Cooperative Institute for Research in Environmental SciencesUniversity of ColoradoBoulderUSA
  2. 2.Department of Physics and Cooperative Institute for Research in Environmental SciencesUniversity of ColoradoBoulderUSA

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