Local Geoid Computation by the Spectral Combination Method

authored by: O. Gitlein, H. Denker, J. Müller
Abstract: The spectral combination method is investigated for the determination of a local geoid in Lower Saxony (Germany) using a global geopotential model, radial gravity gradients from the upcoming GOCE satellite mission, and gravity anomalies. The main goal of this study is to test the method v/ith regard to the validation of GOCE data products. In order to prove the effectiveness and numerical accuracy of the method, the computations are done in a closed-loop simulation based on the EGM96 geopotential model. The gravity field signal is decomposed into long, medium and short wavelength components using corresponding spectral weight functions. The long wavelength information up to about degree n = 30 is computed from a global geopotential model, the medium wavelength part (n = 30-130) is taken from radial gravity gradients at GOCE altitude (250 km), and the high frequency part (n= 130-360) is derived from terrestrial gravity anomalies. The modified spherical Butterworth filter and a cosine filter are tested as spectral weighting functions. The results from the closed-loop simulation are discussed, and an error analysis is done considering the commission and omission errors of the input data sets.
Organisation(s): Institute of Geodesy
Type: Article
Journal: International Association of Geodesy Symposia
Volume: 129
Pages: 179-184
No. of pages: 6
ISSN: 0939-9585
Publication date: 09.2005
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Computers in Earth Sciences, Geophysics
Electronic version(s): https://doi.org/10.1007/3-540-26932-0_31 (Access: Unknown)
: Details in the research portal "Research@Leibniz University"

BibTeX

@article{a7e76233677447a297aa1db6cff13612,
title = "Local Geoid Computation by the Spectral Combination Method",
abstract = "The spectral combination method is investigated for the determination of a local geoid in Lower Saxony (Germany) using a global geopotential model, radial gravity gradients from the upcoming GOCE satellite mission, and gravity anomalies. The main goal of this study is to test the method v/ith regard to the validation of GOCE data products. In order to prove the effectiveness and numerical accuracy of the method, the computations are done in a closed-loop simulation based on the EGM96 geopotential model. The gravity field signal is decomposed into long, medium and short wavelength components using corresponding spectral weight functions. The long wavelength information up to about degree n = 30 is computed from a global geopotential model, the medium wavelength part (n = 30-130) is taken from radial gravity gradients at GOCE altitude (250 km), and the high frequency part (n= 130-360) is derived from terrestrial gravity anomalies. The modified spherical Butterworth filter and a cosine filter are tested as spectral weighting functions. The results from the closed-loop simulation are discussed, and an error analysis is done considering the commission and omission errors of the input data sets.",
keywords = "Downward continuation, Radial gravity gradients, Spectral combination method",
author = "O. Gitlein and H. Denker and J. M{\"u}ller",
year = "2005",
month = sep,
doi = "10.1007/3-540-26932-0_31",
language = "English",
volume = "129",
pages = "179--184",
journal = "International Association of Geodesy Symposia",
issn = "0939-9585",
publisher = "Springer Berlin Heidelberg",
}