Two deterministic and three stochastic modifications of Stokes’s formula: A case study for the Baltic countries
2005 (English)In: Journal of Geodesy, ISSN 0949-7714, E-ISSN 1432-1394, Vol. 79, no 1-3, 11-23 p.Article in journal (Refereed) Published
In regional gravimetric geoid determination, it is customary to use the modified Stokes formula that combines local terrestrial data with a global geopotential model. This study compares two deterministic and three stochastic modification methods for computing a regional geoid over the Baltic countries. The final selection of the best modification method is made by means of two accuracy estimates: the expected global mean square error of the geoid estimator, and the statistics of the post-fit residuals between the computed geoid models and precise GPS-levelling data. Numerical results show that the modification methods tested do not provide substantially different results, although the stochastic approaches appear formally better in the selected study area. The 2.8-5.3 cm (RMS) post-fit residuals to the GPS-levelling points indicate the suitability of the new geoid model for many practical applications. Moreover, the numerical comparisons reveal a one-dimensional offset between the regional vertical datum and the geoid models based upon the new GRACE-only geopotential model GGM01s. This gives an impression of a greater reliability of the new model compared to the earlier, EGM96-based and somewhat tilted regional geoid models for the same study area.
Place, publisher, year, edition, pages
2005. Vol. 79, no 1-3, 11-23 p.
IdentifiersURN: urn:nbn:se:kth:diva-10820DOI: 10.1007/s00190-005-0438-1ISI: 000229802600002ScopusID: 2-s2.0-21444460881OAI: oai:DiVA.org:kth-10820DiVA: diva2:228031
QC 201111092009-07-232009-07-232011-11-09Bibliographically approved