Importance of numerical ocean modelling and in situ ocean bottom pressure observations for satellite gravimetry from GRACE and GRACE-FO
The GRACE and GRACE-FO satellites observe the redistribution of mass in terrestrial water storage, ice sheets, oceans, atmosphere, and solid Earth. Because GRACE data is typically accumulated into monthly-mean gravity fields, an a priori background model, namely the Atmosphere and Ocean Dealiasing L...
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Freie Universität Berlin
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ftgfzpotsdam:oai:gfzpublic.gfz-potsdam.de:item_5004445 2023-05-15T14:02:23+02:00 Importance of numerical ocean modelling and in situ ocean bottom pressure observations for satellite gravimetry from GRACE and GRACE-FO Poropat, L. 2020 https://gfzpublic.gfz-potsdam.de/pubman/item/item_5004445 eng eng Freie Universität Berlin info:eu-repo/semantics/altIdentifier/doi/10.17169/refubium-27670 https://gfzpublic.gfz-potsdam.de/pubman/item/item_5004445 info:eu-repo/semantics/doctoralThesis 2020 ftgfzpotsdam https://doi.org/10.17169/refubium-27670 2022-09-14T05:57:34Z The GRACE and GRACE-FO satellites observe the redistribution of mass in terrestrial water storage, ice sheets, oceans, atmosphere, and solid Earth. Because GRACE data is typically accumulated into monthly-mean gravity fields, an a priori background model, namely the Atmosphere and Ocean Dealiasing Level 1B (AOD1B) product, is applied to remove non-tidal variability that would otherwise alias into the monthly solutions. The main disadvantage of AOD1B RL06 compared to its previous release is that it does not simulate the dynamics beneath the Antarctic ice shelves, which can have a strong influence on global ocean circulation. The primary motivation for this work is the development of the new release of AOD1B, but the performed model experiments can also provide useful insight into the influence processes in the Southern Ocean have on global ocean dynamics. To be able to test various model experiments, as well as to compare GRACE gravity field solutions, validation against in situ measured ocean bottom pressure (OBP) is used. The validation is somewhat better suited for submonthly variability of the ocean models than for long-term signals measured by GRACE because the in situ time series are affected by the errors in trend and drift removal on longer temporal scales. The difference between the pointwise in situ and the area-averaging GRACE measuring technique also influences the comparison. It is shown that post-processing choices can severely impact the results of the validation of GRACE fields, so if different solutions are compared, their post-processing needs to be identical. Validation against in situ OBP is used to compare the EGSIEM combined GRACE solution with its five contributing datasets. It is shown that the combined solution is very close to the leading CSR RL05 and ITSG-Grace2016 solutions, outperforming the others. To investigate whether GRACE is able to detect submonthly signals, the ITSG-Grace2016 daily Kalman solution, from which the submonthly atmospheric and oceanic variability has been removed ... Doctoral or Postdoctoral Thesis Antarc* Antarctic Ice Shelves Southern Ocean GFZpublic (German Research Centre for Geosciences, Helmholtz-Zentrum Potsdam) Antarctic Southern Ocean The Antarctic |
institution |
Open Polar |
collection |
GFZpublic (German Research Centre for Geosciences, Helmholtz-Zentrum Potsdam) |
op_collection_id |
ftgfzpotsdam |
language |
English |
description |
The GRACE and GRACE-FO satellites observe the redistribution of mass in terrestrial water storage, ice sheets, oceans, atmosphere, and solid Earth. Because GRACE data is typically accumulated into monthly-mean gravity fields, an a priori background model, namely the Atmosphere and Ocean Dealiasing Level 1B (AOD1B) product, is applied to remove non-tidal variability that would otherwise alias into the monthly solutions. The main disadvantage of AOD1B RL06 compared to its previous release is that it does not simulate the dynamics beneath the Antarctic ice shelves, which can have a strong influence on global ocean circulation. The primary motivation for this work is the development of the new release of AOD1B, but the performed model experiments can also provide useful insight into the influence processes in the Southern Ocean have on global ocean dynamics. To be able to test various model experiments, as well as to compare GRACE gravity field solutions, validation against in situ measured ocean bottom pressure (OBP) is used. The validation is somewhat better suited for submonthly variability of the ocean models than for long-term signals measured by GRACE because the in situ time series are affected by the errors in trend and drift removal on longer temporal scales. The difference between the pointwise in situ and the area-averaging GRACE measuring technique also influences the comparison. It is shown that post-processing choices can severely impact the results of the validation of GRACE fields, so if different solutions are compared, their post-processing needs to be identical. Validation against in situ OBP is used to compare the EGSIEM combined GRACE solution with its five contributing datasets. It is shown that the combined solution is very close to the leading CSR RL05 and ITSG-Grace2016 solutions, outperforming the others. To investigate whether GRACE is able to detect submonthly signals, the ITSG-Grace2016 daily Kalman solution, from which the submonthly atmospheric and oceanic variability has been removed ... |
format |
Doctoral or Postdoctoral Thesis |
author |
Poropat, L. |
spellingShingle |
Poropat, L. Importance of numerical ocean modelling and in situ ocean bottom pressure observations for satellite gravimetry from GRACE and GRACE-FO |
author_facet |
Poropat, L. |
author_sort |
Poropat, L. |
title |
Importance of numerical ocean modelling and in situ ocean bottom pressure observations for satellite gravimetry from GRACE and GRACE-FO |
title_short |
Importance of numerical ocean modelling and in situ ocean bottom pressure observations for satellite gravimetry from GRACE and GRACE-FO |
title_full |
Importance of numerical ocean modelling and in situ ocean bottom pressure observations for satellite gravimetry from GRACE and GRACE-FO |
title_fullStr |
Importance of numerical ocean modelling and in situ ocean bottom pressure observations for satellite gravimetry from GRACE and GRACE-FO |
title_full_unstemmed |
Importance of numerical ocean modelling and in situ ocean bottom pressure observations for satellite gravimetry from GRACE and GRACE-FO |
title_sort |
importance of numerical ocean modelling and in situ ocean bottom pressure observations for satellite gravimetry from grace and grace-fo |
publisher |
Freie Universität Berlin |
publishDate |
2020 |
url |
https://gfzpublic.gfz-potsdam.de/pubman/item/item_5004445 |
geographic |
Antarctic Southern Ocean The Antarctic |
geographic_facet |
Antarctic Southern Ocean The Antarctic |
genre |
Antarc* Antarctic Ice Shelves Southern Ocean |
genre_facet |
Antarc* Antarctic Ice Shelves Southern Ocean |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.17169/refubium-27670 https://gfzpublic.gfz-potsdam.de/pubman/item/item_5004445 |
op_doi |
https://doi.org/10.17169/refubium-27670 |
_version_ |
1766272655993864192 |