ISG

   International Service for the Geoid

   

Search in ISG Website



Links:










      

      

Services - Geoid Repository


Regional Models

Colorado - USA (ColRLSC-IAPG2019)


  Authors: M. Willberg, et al.   Created: 2019    Resp: M. Willberg  
                       Status: PUBLIC   Licence: CC BY 4.0

Description:
The ColRLSC-IAPG2019 gravimetric quasi-geoid and geoid models have been computed by the Institute of Astronomical and Physical Geodesy, 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, the latter being filtered for the reduction of high-frequency noise. The computation is based on the remove-compute-restore technique with XGM2018 as global geopotential and Earth2014 / ERTM2160 for the topographic gravity effects. Height anomalies are calculated by a one-step Residual Least-Squares Collocation (RLSC, Willberg et al. 2019), also including full covariance information from the high-resolution global geopotential model. The classical formula by Heiskanen and Moritz (1967) is used for the geoid/quasi-geoid separation. This conversion is based on strong simplifications and has been computed only for the purpose of the "Colorado experiment", since the ColRLSC-IAPG2019 solution is mainly focussed on the quasi-geoid computation. The accuracy of the quasi-geoid and geoid models, when compared against GSVS17 GPS/leveling, is equal to 2.9 cm and 3.1 cm, respectively.

Model Citations:
M. Willberg, P. Zingerle, R. Pail (2019). The IAPG quasi-geoid based on Residual Least-Squares Collocation for the Colorado Experiment: ColRLSC-IAPG2019. V. 1.0. GFZ Data Services. DOI: 10.5880/isg.2019.001

M. Willberg, P. Zingerle, R. Pail (2019). The IAPG geoid based on Residual Least-Squares Collocation for the Colorado Experiment: ColRLSC-IAPG2019. V. 1.0. GFZ Data Services. DOI: 10.5880/isg.2019.002

References:
M. Willberg, P. Zingerle, R. Pail (2019). Residual least-squares collocation: use of covariance matrices from high-resolution global geopotential models. Journal of Geodesy, 93, pp. 1739-1757. DOI: 10.1007/s00190-019-01279-1

M. Willberg, P. Zingerle, R. Pail (2020). Integration of airborne gravimetry data filtering into residual least-squares collocation: example from the 1 cm geoid experiment. Journal of Geodesy, 94, 75. DOI: 10.1007/s00190-020-01396-2

Digital object identifiers:
DOI: 10.5880/isg.2019.001 (quasi-geoid in ISG format)
DOI: 10.5880/isg.2019.002 (geoid in ISG format)

COLORADO