Combination of GRACE monthly gravity field solutions from different processing strategies
We combine the publicly available GRACE monthly gravity field time series to produce gravity fields with reduced systematic errors. We first compare the monthly gravity fields in the spatial domain in terms of signal and noise. Then, we combine the individual gravity fields with comparable signal co...
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ftunivbern:oai:boris.unibe.ch:113820 2023-08-20T04:01:51+02:00 Combination of GRACE monthly gravity field solutions from different processing strategies Jean, Yoomin Meyer, Ulrich Jäggi, Adrian 2018 application/pdf https://boris.unibe.ch/113820/1/s00190-018-1123-5.pdf https://boris.unibe.ch/113820/ eng eng Springer https://boris.unibe.ch/113820/ info:eu-repo/semantics/openAccess Jean, Yoomin; Meyer, Ulrich; Jäggi, Adrian (2018). Combination of GRACE monthly gravity field solutions from different processing strategies. Journal of geodesy, 92(11), pp. 1313-1328. Springer 10.1007/s00190-018-1123-5 <http://dx.doi.org/10.1007/s00190-018-1123-5> 520 Astronomy info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion PeerReviewed 2018 ftunivbern https://doi.org/10.1007/s00190-018-1123-5 2023-07-31T21:42:38Z We combine the publicly available GRACE monthly gravity field time series to produce gravity fields with reduced systematic errors. We first compare the monthly gravity fields in the spatial domain in terms of signal and noise. Then, we combine the individual gravity fields with comparable signal content, but diverse noise characteristics. We test five different weighting schemes: equal weights, non-iterative coefficient-wise, order-wise, or field-wise weights, and iterative field-wise weights applying variance component estimation (VCE). The combined solutions are evaluated in terms of signal and noise in the spectral and spatial domains. Compared to the individual contributions, they in general show lower noise. In case the noise characteristics of the individual solutions differ significantly, the weighted means are less noisy, compared to the arithmetic mean: The non-seasonal variability over the oceans is reduced by up to 7.7% and the root mean square (RMS) of the residuals of mass change estimates within Antarctic drainage basins is reduced by 18.1% on average. The field-wise weighting schemes in general show better performance, compared to the order- or coefficient-wise weighting schemes. The combination of the full set of considered time series results in lower noise levels, compared to the combination of a subset consisting of the official GRACE Science Data System gravity fields only: The RMS of coefficient-wise anomalies is smaller by up to 22.4% and the non-seasonal variability over the oceans by 25.4%. This study was performed in the frame of the European Gravity Service for Improved Emergency Management (EGSIEM; http://www.egsiem.eu) project. The gravity fields provided by the EGSIEM scientific combination service (ftp://ftp.aiub.unibe.ch/EGSIEM/) are combined, based on the weights derived by VCE as described in this article. Article in Journal/Newspaper Antarc* Antarctic BORIS (Bern Open Repository and Information System, University of Bern) Antarctic Journal of Geodesy 92 11 1313 1328 |
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Open Polar |
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BORIS (Bern Open Repository and Information System, University of Bern) |
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ftunivbern |
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English |
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520 Astronomy |
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520 Astronomy Jean, Yoomin Meyer, Ulrich Jäggi, Adrian Combination of GRACE monthly gravity field solutions from different processing strategies |
topic_facet |
520 Astronomy |
description |
We combine the publicly available GRACE monthly gravity field time series to produce gravity fields with reduced systematic errors. We first compare the monthly gravity fields in the spatial domain in terms of signal and noise. Then, we combine the individual gravity fields with comparable signal content, but diverse noise characteristics. We test five different weighting schemes: equal weights, non-iterative coefficient-wise, order-wise, or field-wise weights, and iterative field-wise weights applying variance component estimation (VCE). The combined solutions are evaluated in terms of signal and noise in the spectral and spatial domains. Compared to the individual contributions, they in general show lower noise. In case the noise characteristics of the individual solutions differ significantly, the weighted means are less noisy, compared to the arithmetic mean: The non-seasonal variability over the oceans is reduced by up to 7.7% and the root mean square (RMS) of the residuals of mass change estimates within Antarctic drainage basins is reduced by 18.1% on average. The field-wise weighting schemes in general show better performance, compared to the order- or coefficient-wise weighting schemes. The combination of the full set of considered time series results in lower noise levels, compared to the combination of a subset consisting of the official GRACE Science Data System gravity fields only: The RMS of coefficient-wise anomalies is smaller by up to 22.4% and the non-seasonal variability over the oceans by 25.4%. This study was performed in the frame of the European Gravity Service for Improved Emergency Management (EGSIEM; http://www.egsiem.eu) project. The gravity fields provided by the EGSIEM scientific combination service (ftp://ftp.aiub.unibe.ch/EGSIEM/) are combined, based on the weights derived by VCE as described in this article. |
format |
Article in Journal/Newspaper |
author |
Jean, Yoomin Meyer, Ulrich Jäggi, Adrian |
author_facet |
Jean, Yoomin Meyer, Ulrich Jäggi, Adrian |
author_sort |
Jean, Yoomin |
title |
Combination of GRACE monthly gravity field solutions from different processing strategies |
title_short |
Combination of GRACE monthly gravity field solutions from different processing strategies |
title_full |
Combination of GRACE monthly gravity field solutions from different processing strategies |
title_fullStr |
Combination of GRACE monthly gravity field solutions from different processing strategies |
title_full_unstemmed |
Combination of GRACE monthly gravity field solutions from different processing strategies |
title_sort |
combination of grace monthly gravity field solutions from different processing strategies |
publisher |
Springer |
publishDate |
2018 |
url |
https://boris.unibe.ch/113820/1/s00190-018-1123-5.pdf https://boris.unibe.ch/113820/ |
geographic |
Antarctic |
geographic_facet |
Antarctic |
genre |
Antarc* Antarctic |
genre_facet |
Antarc* Antarctic |
op_source |
Jean, Yoomin; Meyer, Ulrich; Jäggi, Adrian (2018). Combination of GRACE monthly gravity field solutions from different processing strategies. Journal of geodesy, 92(11), pp. 1313-1328. Springer 10.1007/s00190-018-1123-5 <http://dx.doi.org/10.1007/s00190-018-1123-5> |
op_relation |
https://boris.unibe.ch/113820/ |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1007/s00190-018-1123-5 |
container_title |
Journal of Geodesy |
container_volume |
92 |
container_issue |
11 |
container_start_page |
1313 |
op_container_end_page |
1328 |
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1774712222129324032 |