Topographic/isostatic evaluation of new-generation GOCE gravity field models
We use gravity implied by the Earth’s rock-equivalent topography (RET) and modelled isostatic compensation masses to evaluate the new global gravity field models (GGMs) from European Space Agency (ESA)’s Gravity Field and Steady-State Ocean Circulation Explorer (GOCE) satellite gravimetry mission. T...
Published in: | Journal of Geophysical Research: Solid Earth |
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American Geophysical Union
2012
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Online Access: | https://hdl.handle.net/20.500.11937/44595 https://doi.org/10.1029/2011JB008878 |
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ftcurtin:oai:espace.curtin.edu.au:20.500.11937/44595 2023-06-11T04:05:55+02:00 Topographic/isostatic evaluation of new-generation GOCE gravity field models Hirt, Christian Kuhn, Michael Featherstone, Will Göttl, F. 2012 fulltext https://hdl.handle.net/20.500.11937/44595 https://doi.org/10.1029/2011JB008878 unknown American Geophysical Union http://hdl.handle.net/20.500.11937/44595 doi:10.1029/2011JB008878 Journal Article 2012 ftcurtin https://doi.org/20.500.11937/4459510.1029/2011JB008878 2023-05-30T19:43:39Z We use gravity implied by the Earth’s rock-equivalent topography (RET) and modelled isostatic compensation masses to evaluate the new global gravity field models (GGMs) from European Space Agency (ESA)’s Gravity Field and Steady-State Ocean Circulation Explorer (GOCE) satellite gravimetry mission. The topography is now reasonably well-known over most of the Earth’s landmasses, and also where conventional GGM evaluation is prohibitive due to the lack (or unavailability) of ground-truth gravity data. We construct a spherical harmonic representation of Earth’s RET to derive band-limited topography-implied gravity, and test the somewhat simplistic Airy/Heiskanen and Pratt/Hayford hypotheses of isostatic compensation, but which did not improve the agreement between gravity from the uncompensated RET and GOCE. The third-generation GOCE GGMs (based on 12 months of space gravimetry) resolve the Earth’s gravity field effectively up to spherical harmonic degree 200–220 (90–100 km resolution). Such scales could not be resolved from satellites before GOCE. From the three different GOCE processing philosophies currently in use by ESA, the time-wise and direct approaches exhibit the highest sensitivity to short-scale gravity recovery, being better than the space-wise approach. Our topography-implied gravity comparisons bring evidence of improvements from GOCE to gravity field knowledge over the Himalayas, Africa, the Andes, Papua New Guinea and Antarctic regions. In attenuated form, GOCE captures topography-implied gravity signals up to degree 250 (80 km resolution), suggesting that other signals (originating, e.g., from the crust-mantle boundary and buried loads) are captured as well, which might now improve our knowledge on the Earth’s lithosphere structure at previously unresolved spatial scales. Article in Journal/Newspaper Antarc* Antarctic Curtin University: espace Antarctic Pratt ENVELOPE(176.683,176.683,-85.400,-85.400) Journal of Geophysical Research: Solid Earth 117 B5 n/a n/a |
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Open Polar |
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Curtin University: espace |
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ftcurtin |
language |
unknown |
description |
We use gravity implied by the Earth’s rock-equivalent topography (RET) and modelled isostatic compensation masses to evaluate the new global gravity field models (GGMs) from European Space Agency (ESA)’s Gravity Field and Steady-State Ocean Circulation Explorer (GOCE) satellite gravimetry mission. The topography is now reasonably well-known over most of the Earth’s landmasses, and also where conventional GGM evaluation is prohibitive due to the lack (or unavailability) of ground-truth gravity data. We construct a spherical harmonic representation of Earth’s RET to derive band-limited topography-implied gravity, and test the somewhat simplistic Airy/Heiskanen and Pratt/Hayford hypotheses of isostatic compensation, but which did not improve the agreement between gravity from the uncompensated RET and GOCE. The third-generation GOCE GGMs (based on 12 months of space gravimetry) resolve the Earth’s gravity field effectively up to spherical harmonic degree 200–220 (90–100 km resolution). Such scales could not be resolved from satellites before GOCE. From the three different GOCE processing philosophies currently in use by ESA, the time-wise and direct approaches exhibit the highest sensitivity to short-scale gravity recovery, being better than the space-wise approach. Our topography-implied gravity comparisons bring evidence of improvements from GOCE to gravity field knowledge over the Himalayas, Africa, the Andes, Papua New Guinea and Antarctic regions. In attenuated form, GOCE captures topography-implied gravity signals up to degree 250 (80 km resolution), suggesting that other signals (originating, e.g., from the crust-mantle boundary and buried loads) are captured as well, which might now improve our knowledge on the Earth’s lithosphere structure at previously unresolved spatial scales. |
format |
Article in Journal/Newspaper |
author |
Hirt, Christian Kuhn, Michael Featherstone, Will Göttl, F. |
spellingShingle |
Hirt, Christian Kuhn, Michael Featherstone, Will Göttl, F. Topographic/isostatic evaluation of new-generation GOCE gravity field models |
author_facet |
Hirt, Christian Kuhn, Michael Featherstone, Will Göttl, F. |
author_sort |
Hirt, Christian |
title |
Topographic/isostatic evaluation of new-generation GOCE gravity field models |
title_short |
Topographic/isostatic evaluation of new-generation GOCE gravity field models |
title_full |
Topographic/isostatic evaluation of new-generation GOCE gravity field models |
title_fullStr |
Topographic/isostatic evaluation of new-generation GOCE gravity field models |
title_full_unstemmed |
Topographic/isostatic evaluation of new-generation GOCE gravity field models |
title_sort |
topographic/isostatic evaluation of new-generation goce gravity field models |
publisher |
American Geophysical Union |
publishDate |
2012 |
url |
https://hdl.handle.net/20.500.11937/44595 https://doi.org/10.1029/2011JB008878 |
long_lat |
ENVELOPE(176.683,176.683,-85.400,-85.400) |
geographic |
Antarctic Pratt |
geographic_facet |
Antarctic Pratt |
genre |
Antarc* Antarctic |
genre_facet |
Antarc* Antarctic |
op_relation |
http://hdl.handle.net/20.500.11937/44595 doi:10.1029/2011JB008878 |
op_doi |
https://doi.org/20.500.11937/4459510.1029/2011JB008878 |
container_title |
Journal of Geophysical Research: Solid Earth |
container_volume |
117 |
container_issue |
B5 |
container_start_page |
n/a |
op_container_end_page |
n/a |
_version_ |
1768377604230873088 |