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Regional Models

Colorado - USA (ColWRRT2019)


  Author: H.A. Abd-Elmotaal   Created: 2019    Resp: H.A. Abd-Elmotaal  
                       Status: PUBLIC   Licence: CC BY 4.0
Description:
The ColWRRT2019 gravimetric geoid model has been computed by the Civil Engineering Department of Minia University. It has 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 110°W ≤ longitude ≤ 102°W, 35°N ≤ latitude ≤ 40°N with a grid spacing of 1' in both latitude and in longitude. The computation is performed by the window remove-restore technique, subtracting the effect of the topographic-isostatic masses of the data window from the reference model to obtain an adapted reference model to be used in the traditional remove-compute-restore procedure. The chosen reference model is xGEOID17RefB, complete to degree and order 2190. The window-reduced gravity anomalies are used to compute the geoid undulations by employing Stokes formula with Meissl modified kernel (with a cap size of 0.5°). The window restore step yields the final geoid. The accuracy of the ColWRRT2019 model, when compared against GSVS17 GPS/leveling, is equal to 3.0 cm.

References:
Hussein A. Abd-Elmotaal (2019). Colorado Detailed Geoid COLgeo2019. Report of the Joint Working Group 2.2.2 "The 1 cm geoid experiment", pp.1-4.
H. Abd-Elmotaal, N. Kühtreiber (2021). Direct Harmonic Analysis for the Ellipsoidal Topographic Potential with Global and Local Validation. Surveys in Geophysics, 42, pp. 159-176, DOI: 10.1007/s10712-020-09614-4
H. Abd-Elmotaal, N. Kühtreiber (2003). Geoid Determination Using Adapted Reference Field, Seismic Moho Depths and Variable Density Contrast. Journal of Geodesy, 77, pp. 77-85, DOI: 10.1007/s00190-002-0300-7


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