Skip to main content

Advertisement

Earth, Planets and Space
Earth, Planets and Space Cover Image
We’d like to understand how you use our websites in order to improve them. Register your interest.
Download PDF

Iberia-Azores Gravity Model (IAGRM) using multi-source gravity data

Earth, Planets and Space volume 58, pages277–286(2006)Cite this article

Abstract

A consistent high precision and high resolution gravity model in the north-east Atlantic off Iberia peninsula using multi-source gravity data, ship-borne and satellite derived gravity anomalies, is presented. A solution strategy based on least squares optimal interpolation was used to assimilate into a coherent gravity model, gravity data with different spectral and spatial resolutions. Satellite derived gravity anomalies from KMS02 model, with an error covariance of 25 mGal2, and marine data carefully edited and validated by bias crossover error adjustment, were used in this study. The observation error variance was determined from ship-borne track adjustment and assigned an independent value for each track determined from error variance propagation. Unbiased ship-borne gravity observations were assimilated into the satellite derived gravity KMS02 model by the least squares optimal interpolation algorithm (OI) with bias removed by applying a regional bias to all ship tracks (OI-b) and alternatively by constraining all ship tracks to KMS02 using bias and tilt (OI-t). External error of the model was determined by comparing with recent surveys and it was verified that OI-t approach improved the final gravity model to an accuracy of about 3 mGal. The effect of different merging approaches on geoid solution was also evaluated and it was verified that the merging process can contribute to improve the geoid accuracy up to 4 cm with the OI-t approach.

References

  1. Andersen, O. B. and P. Knudsen, Global marine gravity field from ERS-1 and Geosat geodetic mission altimetry, J. Geophys. Res., 103(C4), 8129–8137, 1998.

    Article  Google Scholar 

  2. Andersen, O. B., P. Knudsen, S. Kenyon, and R. Trimmer, Recent improvement in the KMS global marine gravity field, Bollettino Geofisica Teorica ed Applicata, 40, 369–377, 1999.

    Google Scholar 

  3. Barzaghi, R. and F. Sansò, Sulla stima empirica della funzione di covarianza, Bollettino di Geodesia e Scienze Affini, XLII(4), 389–415, 1983.

    Google Scholar 

  4. Boutier, F. and P. Courtier, Data assimilation concepts and methods, Meteorological Training Course Lecture Series, ECMWF, 2002.

    Google Scholar 

  5. Catalao, J. and M. J. Sevilla, Inner and minimum constraint adjustment of marine gravity data, Computer and Geosciences, 30(9–10), 949–957, DOI: 10.1016/j.cageo.2004.06.004, 2004.

    Article  Google Scholar 

  6. Childers, V. A., D. C. McAdoo, J. M. Brozena, and S. L. Laxon, New gravity data in the artic Ocean: Comparison of airborne and ERS gravity, J. Geophys. Res., 106, 8871–8886, 2001.

    Article  Google Scholar 

  7. Deng, X., W. E. Featherstone, C. Hwang, and P. A. M. Berry, Estimation of contamination of ERS-2 and Poseidon satellite radar altimetry close to the coasts of Australia, Marine Geodesy, 25, 249–271, DOI: 10.1080/01490410290051572, 2002.

    Article  Google Scholar 

  8. Fernandes, M. J., A. Gidskehaug, D. Solheim, M. Mork, P. Jaccard, and J. Catalao, Gravimetric and Hydrographic campaign in Azores, in Proceedings of the I Luso-Spanish Assembly in Geodesy and Geophysics, Almeria, Spain, 9–13 Feb., University of Almeria, p. 113, 1998.

    Google Scholar 

  9. Forsberg, R., Local covariance functions and density distributions, Dept. of Geodetic Science and Surveying, Rep. No. 356, The Ohio State University, Columbus, Ohio, 1984.

    Google Scholar 

  10. Forsberg, R. and J. M. Brozena, The Greenland airborne gravity project— comparison of airborne and terrestrial gravity data, in BGI, Bulletin D’Information No. 71, Workshop on marine gravity data validation, Toulouse, Oct. 27–28, 55–58, 1992.

    Google Scholar 

  11. Forsberg, R. and C. C. Tscherning, The use of height data in gravity field approximation by collocation, J. Geophys. Res., 86(B9), Sept. 10, 7843–7854, 1981.

    Article  Google Scholar 

  12. Forsberg, R., K. Hehl, L. Bastos, A. Giskehaug, and U. Meyer, Development of an airborne geoid mapping system for coastal oceanography (AGMASCO), in Proceedings of the International Symposium on Gravity, Geoid and Marine Geodesy, GRAGEOMAR, edited by J. Segawa, H. Fujimoto, and S. Okubo, The University of Tokyo, Tokyo, Sept. 30–Oct. 5, 1996, Springer-Verlag, pp. 163–170, 1997.

    Google Scholar 

  13. Heiskanen, W. A. and H. Moritz, Physical Geodesy, W. H. Freeman and Company, San Francisco, 1967.

    Google Scholar 

  14. Kearsley, A. H. W., R. Forsberg, A. Olesen, L. Bastos, K. Hehl, U. Meyer, and A. Gidskehaug, Airborne gravimetry used in precise geoid computations by ring integration, Journal of Geodesy, 72, 600–605, 1998.

    Article  Google Scholar 

  15. Kern, M., P. Schwarz, and N. Sneeuw, A study on the combination of satellite, airborne, and terrestrial gravity data, Journal of Geodesy, 77, 217–225, DOI 10.1007/s00190-003-0313-x, 2003.

    Article  Google Scholar 

  16. Lemoine, F. G., D. E. Smith, L. Kunz, R. Smith, E. C. Pavlis, N. K. Pavlis, S. M. Klosko, D. S. Chinn, M. H. Torrence, R. G. Williamson, C. M. Cox, K. E. Rachlin, Y. M. Wang, S. C. Kenyon, R. Salman, R. Trimmer, R. H. Rapp, and R. S. Nerem, The development of the NASA GSFC and NIMA Joint Geopotential Model, in Proceedings of the International Symposium on Gravity, Geoid and Marine Geodesy, GRAGEOMAR, edited by J. Segawa, H. Fujimoto, and S. Okubo, The University of Tokyo, Tokyo, Sept. 30–Oct. 5, Springer-Verlag, pp. 461–469, 1997.

    Google Scholar 

  17. Moritz, H., Advanced Physical Geodesy, 500 pp., H. Wichmann Verlag, Karlsruhe, 1980.

    Google Scholar 

  18. Navarro, A., J. Catalao, J. M. Miranda, and R. M. S. Fernandes, Estimation of the Terceira island (Azores) main strain rates from GPS data, Earth Planets Space, 55(10), 637–642, 2003.

    Article  Google Scholar 

  19. Olesen, A. V. and R. Forsberg, Azores airborne gravity processing, Personal communication, Copenhagen, March 1999.

    Google Scholar 

  20. Olesen, A. V., O. B. Andersen, and C. C. Tscherning, Merging airborne gravity and gravity derived from satellite altimetry: test cases along the coast of Greenland, Studia Geophys. Geod., 46, 387–394, 2002.

    Article  Google Scholar 

  21. Rodriguez-Velasco, G., M. J. Sevilla, and C. Toro, Dependence of mean sea surface from altimeter data on the reference model used, Marine Geodesy, 25, 289–312, DOI:10.1080/01490410290051590, 2002.

    Article  Google Scholar 

  22. Sandwell, D. and W. H. F. Smith, Marine gravity anomaly from Geosat and ERS1 satellite altimetry, J. Geophys. Res., 102(B5), 10039–10054, 1997.

    Article  Google Scholar 

  23. Schwarz, K. P. and Y. Li, What can airborne gravity contribute to geoid determination?, J. Geophys. Res., 101(B8), 17873–17881, 1996.

    Article  Google Scholar 

  24. Strykowski, G. and R. Forsberg, Operational Merging of Satellite, Airborne and Surface Gravity Data by Draping Techniques, in Geodesy on the Move—gravity, geoid, geodynamics and Antarctica, Proceedings IAG scientific assembly, Rio de Janeiro, Sept 3–9 1997, Forsberg, Feissel and Dietrich (eds.), IAG symposia 119, pp. 243–248, Springer Verlag, Berlin, 1998.

    Google Scholar 

  25. Timmen, L., L. Bastos, R. Forsberg, A. Gidskehaug, and U. Meyer, Airborne Gravity Field Surveying for Oceanography, Geology and Geodesy—Experiences from AGMASCO, in IAG Symposia, Volume 121, Springer Verlag, 2002.

  26. Tscherning, C. C., Local approximation of the gravity potential by least squares collocation, in Proceedings of the International Summer School on Local Gravity Field Approximation, edited by K. P. Schwarz, Beijing, China, Aug. 21–Sept. 4, 1984, Pub. 60003, Univ. of Calgary, Calgary, Canada, pp. 277–362, 1985.

    Google Scholar 

  27. Wessel, P. and W. Smith, Free software helps map and display data, Eos Trans. AGU, 72, 441, 1991.

    Article  Google Scholar 

Download references

Author information

Affiliations

  1. LATTEX, University of Lisbon, Faculty of Sciences, Campo Grande, 1749-016, Lisbon, Portugal
    • J. Catalao
Authors
  1. J. Catalao
    View author publications
    You can also search for this author in

Corresponding author

Correspondence to J. Catalao.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Catalao, J. Iberia-Azores Gravity Model (IAGRM) using multi-source gravity data. Earth Planet Sp 58, 277–286 (2006). https://doi.org/10.1186/BF03351924

Download citation

Key words

  • Gravity
  • merging techniques
  • Iberia-Azores
  • optimal interpolation