A hybrid approach for recovering high-resolution temporal gravity fields from satellite laser ranging
Abstract A new approach to recover time-variable gravity fields from satellite laser ranging (SLR) is presented. It takes up the concept of lumped coefficients by representing the temporal changes of the Earth’s gravity field by spatial patterns via combinations of spherical harmonics. These pattern...
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Springer Science and Business Media LLC
2020
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crspringernat:10.1007/s00190-020-01460-x 2023-05-15T16:30:24+02:00 A hybrid approach for recovering high-resolution temporal gravity fields from satellite laser ranging Löcher, Anno Kusche, Jürgen Rheinische Friedrich-Wilhelms-Universität Bonn 2020 http://dx.doi.org/10.1007/s00190-020-01460-x http://link.springer.com/content/pdf/10.1007/s00190-020-01460-x.pdf http://link.springer.com/article/10.1007/s00190-020-01460-x/fulltext.html en eng Springer Science and Business Media LLC https://creativecommons.org/licenses/by/4.0 https://creativecommons.org/licenses/by/4.0 CC-BY Journal of Geodesy volume 95, issue 1 ISSN 0949-7714 1432-1394 Computers in Earth Sciences Geochemistry and Petrology Geophysics journal-article 2020 crspringernat https://doi.org/10.1007/s00190-020-01460-x 2022-01-04T15:09:19Z Abstract A new approach to recover time-variable gravity fields from satellite laser ranging (SLR) is presented. It takes up the concept of lumped coefficients by representing the temporal changes of the Earth’s gravity field by spatial patterns via combinations of spherical harmonics. These patterns are derived from the GRACE mission by decomposing the series of monthly gravity field solutions into empirical orthogonal functions (EOFs). The basic idea of the approach is then to use the leading EOFs as base functions in the gravity field modelling and to adjust the respective scaling factors straightforward within the dynamic orbit computation; only for the lowest degrees, the spherical harmonic coefficients are estimated separately. As a result, the estimated gravity fields have formally the same spatial resolution as GRACE. It is shown that, within the GRACE time frame, both the secular and the seasonal signals in the GRACE time series are reproduced with high accuracy. In the period prior to GRACE, the SLR solutions are in good agreement with other techniques and models and confirm, for instance, that the Greenland ice sheet was stable until the late 1990s. Further validation is done with the first monthly fields from GRACE Follow-On, showing a similar agreement as with GRACE itself. Significant differences to the reference data only emerge occasionally when zooming into smaller river basins with strong interannual mass variations. In such cases, the approach reaches its limits which are set by the low spectral sensitivity of the SLR satellites and the strong constraints exerted by the EOFs. The benefit achieved by the enhanced spatial resolution has to be seen, therefore, primarily in the proper capturing of the mass signal in medium or large areas rather than in the opportunity to focus on isolated spatial details. Article in Journal/Newspaper Greenland Ice Sheet Springer Nature (via Crossref) Greenland Journal of Geodesy 95 1 |
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Springer Nature (via Crossref) |
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English |
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Computers in Earth Sciences Geochemistry and Petrology Geophysics |
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Computers in Earth Sciences Geochemistry and Petrology Geophysics Löcher, Anno Kusche, Jürgen A hybrid approach for recovering high-resolution temporal gravity fields from satellite laser ranging |
topic_facet |
Computers in Earth Sciences Geochemistry and Petrology Geophysics |
description |
Abstract A new approach to recover time-variable gravity fields from satellite laser ranging (SLR) is presented. It takes up the concept of lumped coefficients by representing the temporal changes of the Earth’s gravity field by spatial patterns via combinations of spherical harmonics. These patterns are derived from the GRACE mission by decomposing the series of monthly gravity field solutions into empirical orthogonal functions (EOFs). The basic idea of the approach is then to use the leading EOFs as base functions in the gravity field modelling and to adjust the respective scaling factors straightforward within the dynamic orbit computation; only for the lowest degrees, the spherical harmonic coefficients are estimated separately. As a result, the estimated gravity fields have formally the same spatial resolution as GRACE. It is shown that, within the GRACE time frame, both the secular and the seasonal signals in the GRACE time series are reproduced with high accuracy. In the period prior to GRACE, the SLR solutions are in good agreement with other techniques and models and confirm, for instance, that the Greenland ice sheet was stable until the late 1990s. Further validation is done with the first monthly fields from GRACE Follow-On, showing a similar agreement as with GRACE itself. Significant differences to the reference data only emerge occasionally when zooming into smaller river basins with strong interannual mass variations. In such cases, the approach reaches its limits which are set by the low spectral sensitivity of the SLR satellites and the strong constraints exerted by the EOFs. The benefit achieved by the enhanced spatial resolution has to be seen, therefore, primarily in the proper capturing of the mass signal in medium or large areas rather than in the opportunity to focus on isolated spatial details. |
author2 |
Rheinische Friedrich-Wilhelms-Universität Bonn |
format |
Article in Journal/Newspaper |
author |
Löcher, Anno Kusche, Jürgen |
author_facet |
Löcher, Anno Kusche, Jürgen |
author_sort |
Löcher, Anno |
title |
A hybrid approach for recovering high-resolution temporal gravity fields from satellite laser ranging |
title_short |
A hybrid approach for recovering high-resolution temporal gravity fields from satellite laser ranging |
title_full |
A hybrid approach for recovering high-resolution temporal gravity fields from satellite laser ranging |
title_fullStr |
A hybrid approach for recovering high-resolution temporal gravity fields from satellite laser ranging |
title_full_unstemmed |
A hybrid approach for recovering high-resolution temporal gravity fields from satellite laser ranging |
title_sort |
hybrid approach for recovering high-resolution temporal gravity fields from satellite laser ranging |
publisher |
Springer Science and Business Media LLC |
publishDate |
2020 |
url |
http://dx.doi.org/10.1007/s00190-020-01460-x http://link.springer.com/content/pdf/10.1007/s00190-020-01460-x.pdf http://link.springer.com/article/10.1007/s00190-020-01460-x/fulltext.html |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland Ice Sheet |
genre_facet |
Greenland Ice Sheet |
op_source |
Journal of Geodesy volume 95, issue 1 ISSN 0949-7714 1432-1394 |
op_rights |
https://creativecommons.org/licenses/by/4.0 https://creativecommons.org/licenses/by/4.0 |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1007/s00190-020-01460-x |
container_title |
Journal of Geodesy |
container_volume |
95 |
container_issue |
1 |
_version_ |
1766020132314808320 |