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Global Gravity Fields from Simulated Level-1 GRACE Data

  • Ulrich MeyerEmail author
  • Björn Frommknecht
  • Frank Flechtner
Chapter
Part of the Advanced Technologies in Earth Sciences book series (ATES)

Abstract

The GRACE satellites deliver high quality GPS code and phase, inter-satellite range and range-rate, non-gravitational acceleration, and star camera observations that can be used to estimate the static and time variable gravity field of the Earth with unprecedented accuracy. Nevertheless, the baseline accuracy that was determined in a pre-launch simulation study could not yet be reached. To find out possible reasons and to give recommendations for an improved data processing, another simulation study using the software, standards and processing strategy actually applied at GFZ in the routine processing of GRACE data is performed. The results point to inaccuracies in present ocean tide models. Additionally, it was found that the accelerometer noise cannot be absorbed sufficiently by the instrument parameters estimated so far and a shortening of the arcs seems to be necessary. Finally, an observed bias in the C20-coefficient of the GRACE gravity field models could be related to a GPS antenna phase centre bias in along-track direction.

Keywords

GRACE Simulation study Gravity field Baseline accuracy 

Notes

Acknowledgment

This is publication no. GEOTECH-1269 of the GEOTECHNOLOGIEN programme of BMBF, grant 03F0423A.

References

  1. Berger C, Biancale R, Ill M, Barlier F (1998) Improvement of the empirical thermospheric model DTM: DTM-94- comparative review on various temporal variations and prospects in space geodesy applications. J. Geod. 72, 161–178.CrossRefGoogle Scholar
  2. Bode A, Biancale R (2006) Mean annual and seasonal atmospheric tide models based on 3-hourly and 6-hourly ECMWF surface pressure data. Scientific Technical Report STR06/01, GeoForschungsZentrum Potsdam, Potsdam.Google Scholar
  3. Ferrari J, Bills BG (1977) A harmonic analysis of lunar topography. Icarus 31(2), 244–259.CrossRefGoogle Scholar
  4. Flechtner F (2007) AOD1B Product description document for product releases 01 to 04, GRACE Project Document, JPL 327–750, rev. 3.1, JPL Pasadena, Ca.Google Scholar
  5. Flechtner F, Schmidt R, Meyer U (2006) De-aliasing of short-term atmospheric and oceanic mass variations for GRACE. In: Flury J, Rummel R, Reigber C, Rothacher M, Boedecker G, Schreiber U (eds.), Observation of the Earth System from Space, Springer-Verlag, Berlin, Heidelberg.Google Scholar
  6. Flechtner F, Dahle CH, Neumayer KH, König R, Förste CH (2009) The release 04 CHAMP and GRACE EIGEN gravity field models. In: Flechtner F, Gruber T, Güntner A, Mandea M, Rothacher M, Schöne T, Wickert J (eds.), Satellite Geodesy and Earth System Science, Springer-Verlag, Berlin, Heidelberg.Google Scholar
  7. Förste C, Flechtner F, Schmidt R, Meyer U, Stubenvoll R, Barthelmes F, König R, Neumayer KH, Rothacher M, Reigber Ch, et al. (2005) A New High Resolution Global Gravity Field Model Derived from Combination of GRACE and CHAMP Mission and Altimetry/Gravimetry Surface Gravity Data. http://www-app2.gfz-potsdam.de/pb1/op/grace/results
  8. Frommknecht B (2007) Integrated Sensor Analysis of the GRACE Mission. Institute for Astronomical and Physical Geodesy, Technical University Munich, Germany.Google Scholar
  9. Gunter B, Ries J, Bettadpur S, Tapley B (2006) A simulation study of the errors of omission and commission for GRACE RL01 gravity fields. J. Geod. 80, 341–351.CrossRefGoogle Scholar
  10. Ilk KH, Flury J, Rummel R, Schwintzer P, Bosch W, Haas C, Schröter J, Stammer D, Zahel W, Miller H, et al. (2005) Mass Transport and Mass Distribution in the Earth System – Contribution of the New Generation of Satellite Gravity and Altimetry Missions to Geosciences, 2nd ed., Proposal for a German Priority Research Program, GOCE Project Office Germany, Technical University Munich, GeoForschungsZentrum Potsdam.Google Scholar
  11. Kim J (2000) Simulation Study of a Low-Low Satellite-to-Satellite Tracking Mission. University of Texas at Austin, Austin, TX.Google Scholar
  12. Klokčoník J, Wagner CA, Kostelecký J, Bezdek A, Novák P, McAdoo D (2008) Variations in the accuracy of gravity recovery due to ground track variability: GRACE, CHAMP, and GOCE. J. Geod., doi: 10.1007/s00190-008-0222-0.Google Scholar
  13. Knocke PC, Ries JC, Tapley BD (1988) Earth radiation pressure effects on satellites. AIAA-88-4992-CP. In: Proc. of the AIAA/AAS Astrodynamics Conference (1988), pp. 577–586.Google Scholar
  14. Lyard F, Lefevre F, Letellier T, Francis O (2006) Modelling the global ocean tides: Modern insights from FES2004. Ocean Dyn. 56, 394–415.CrossRefGoogle Scholar
  15. Savcenko R, Bosch W (2008) EOT08a – Empirical Ocean Tide Model from Multi-Mission Satellite Altimetry. Deutsches Geodätisches Forschungsinstitut, München.Google Scholar
  16. Schmidt R (2007) Zur Bestimmung des cm-Geoids und dessen zeitlicher Variationen mit GRACE. GeoForschungsZentrum Potsdam, PotsdamGoogle Scholar
  17. Tapley B, Bettadpur S, Watkins M, Reigber C (2004) The gravity recovery and climate experiment: Mission overview and early results. Geophys. Res. Lett. 31, L09607.CrossRefGoogle Scholar
  18. Tapley B, Ries J, Bettadpur S, Chambers D, Cheng M, Condi F, Gunter B, Kang Z, Nagel P, Pastor R, et al. (2005) GGM02 – An improved earth gravity field model from GRACE. J. Geod. 79, 467–478.CrossRefGoogle Scholar
  19. Thomas J (1999) An Analysis of the Gravity Field Estimation Based on Dual-1-Way Intersatellite Biased Ranging. Jet Propulsion Laboratory, Pasadena, CA.Google Scholar
  20. Thomas M, Sündermann J, Maier-Reimer E (2001) Consideration of ocean tides in an OGCM and impacts on subseasonal to decadal polar motion excitation. Geophys. Res. Lett. 12, 2457.CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  • Ulrich Meyer
    • 1
    • 2
  • Björn Frommknecht
    • 3
    • 4
    • 5
  • Frank Flechtner
    • 6
  1. 1.Helmholtz-Zentrum Potsdam, Deutsches GeoForschungsZentrum (GFZ)WeβlingGermany
  2. 2.Astronomical Institute, University of BernBernSwitzerland
  3. 3.RHEA S.A.Louvain La NeuveBelgium
  4. 4.ESA/ESRINFrascatiItaly
  5. 5.Institut für Astronomische und Physikalische Geodäsie (IAPG), Technische Universität MünchenMünchenGermany
  6. 6.Department 1: Geodesy and Remote SensingHelmholtz Centre Potsdam, GFZ German Research Centre for GeosciencesPotsdamGermany

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