10.5880/isg.2019.020 eng dataset GFZ German Research Centre for Geosciences datapub@gfz-potsdam.de http://www.gfz-potsdam.de Helmholtz-Centre Potsdam - GFZ German Research Centre for Geosciences Helmholtz-Centre Potsdam - GFZ German Research Centre for Geosciences pointOfContact 2022-06-09 urn:ogc:def:crs:EPSG:4326 The CGS quasi-geoid based on FFT with degree-banded modification of the Stokes kernel for the Colorado Experiment: ColFFTDB-CGS2019 2022-06-09 revision 2019 creation doi:10.5880/isg.2019.020 Véronneau, Marc Canadian Geodetic Survey (CGS), Natural Resources Canada, Ottawa, Canada author Huang, Jianliang Canadian Geodetic Survey (CGS), Natural Resources Canada, Ottawa, Canada author GFZ Data Services publisher The ColFFTDB-CGS2019 gravimetric quasi-geoid model has been computed by the Canadian Geodetic Survey (CGS), Natural Resources Canada. 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 model is 110°W ≤ longitude ≤ 102°W, 35°N ≤ latitude ≤ 40°N with a grid spacing of 1' in both latitude and in longitude. The solution is based on the Stokes-Helmert method, which is used with the degree-banded Stokes kernel modification (Huang and Véronneau, 2013). A band-wise spectral scheme is developed to combine the global model, airborne and surface gravity data, contributing to low-, medium- and high-degree bands of the geoid, respectively. In particular, the global gravity model provides entirely the low-degree band up to degree 150 from where it goes into transition with the surface gravity data up to degree 210. The surface gravity data complete the geoid frequencies up to degree 10800 with complement information from SRTM 3″ digital terrain model. As for the GRAV-D airborne gravity data, they provide corrective values directly to the geoid model, contributing between degrees 210 and 790 with smooth transition at each end. The geoid computation is performed by Fast Fourier Transform (FFT) numerical integration and then the quasi-geoid model is obtained by adding a classic geoid to quasi-geoid correction grid. The accuracy of the quasi-geoid model, when compared against GSVS17 GPS/leveling, is equal to 1.8 cm. The geoid model is provided in ISG format 2.0 (ISG Format Specifications), while the file in its original data format is available at the model ISG webpage. Huang, Jianliang Canadian Geodetic Survey (CGS), Natural Resources Canada, Ottawa, Canada jianliang.huang@NRCan-RNCan.gc.ca pointOfContact ISG Staff International Service for the Geoid (ISG) isg@polimi.it http://www.isgeoid.polimi.it/ informtion pointOfContact Geodesy Geoid model ISG Fast Fourier Transform Degree-banded Stokes kernel modification Colorado experiment EARTH SCIENCE > SOLID EARTH > GEODETICS > GEOID CHARACTERISTICS EARTH SCIENCE > SOLID EARTH > GRAVITY/GRAVITATIONAL FIELD > GRAVITY NASA/GCMD Earth Science Keywords publication CC BY 4.0 CC BY 4.0 https://www.isgeoid.polimi.it/Geoid/America/USA/reg_listCOLORADOproject.html URL IsPartOf 10.1007/s00190-013-0645-0 DOI IsDocumentedBy 10.5194/essd-13-1653-2021 DOI References http://www.isgeoid.polimi.it/ URL References 10.5880/isg.2019.021 DOI IsVariantFormOf eng geoscientificInformation Gravimetric quasi-geoid model ColFFTDB-CGS2019 -109.992 -102.008 35.0083 39.9917 http://doi.org/10.5880/isg.2019.020 WWW:LINK-1.0-http--link Data Access - DOI Data Access - DOI information