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Regional Models

Colorado - USA (ColSRBF2019)

  Authors: Q. Liu, et al.   Created: 2019    Resp: Q. Liu  
                       Status: PUBLIC   Licence: CC BY 4.0
The ColSRBF2019 gravimetric quasi-geoid and geoid models have been computed by the Deutsches Geodätisches Forschungsinstitut (DGFI), Technical University of Munich. They have been worked out in the frame of the International Association of Geodesy Joint Working Group 2.2.2 "The 1 cm geoid experiment" and the so called "Colorado experiment". The area covered by the models is 251°E ≤ longitude ≤ 257°E, 36°N ≤ latitude ≤ 39°N with a grid spacing of 1' in both latitude and in longitude. Input data include terrestrial and airborne gravity observations, both used with their original observation sites. The computation method is based on spherical radial basis functions (SRBFs), using the Shannon function and the Cubic Polynomial (CuP) function for the terrestrial and airborne data, respectively. The computation is performed in the framework of a remove-compute-restore procedure, taking XGM2016 as global gravity model and Earth2014 / ERTM2160 for the topographic gravity effects. The terrestrial and airborne observations are combined within a parameter estimation procedure, and the relative weight between these two types of observations are determined by the method of variance component estimation (VCE). The classical formula by Heiskanen and Moritz (1967) is used for quasi-geoid to geoid conversion. The accuracy of the quasi-geoid and geoid models, when compared against GSVS17 GPS/leveling, is equal to 2.9 cm and 3.0 cm, respectively.

Q. Liu, M. Schmidt, L. Sánchez, M. Willberg (2019). Regional gravity field refinement for (quasi-) geoid determination based on spherical radial basis functions in Colorado. Journal of Geodesy, 94, 99. DOI: 10.1007/s00190-020-01431-2