The Effect of Spatially Correlated Errors on Sea Surface Height Retrieval from SWOT Altimetry
The upcoming technology of wide-swath altimetry from space will enable monitoring the ocean surface at 45 times better spatial resolution and 23 times better accuracy than traditional nadir altimeters. This development will provide a chance to directly observe submesoscale sea surface height (SSH) v...
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Online Access: | http://hdl.handle.net/10919/116251 https://doi.org/10.3390/rs15174277 |
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ftvirginiatec:oai:vtechworks.lib.vt.edu:10919/116251 2024-09-15T18:10:05+00:00 The Effect of Spatially Correlated Errors on Sea Surface Height Retrieval from SWOT Altimetry Remote Sensing Yaremchuk, Max Beattie, Christopher Panteleev, Gleb D’Addezio, Joseph M. Smith, Scott 2023-08-31 application/pdf http://hdl.handle.net/10919/116251 https://doi.org/10.3390/rs15174277 en eng MDPI Yaremchuk, M.; Beattie, C.; Panteleev, G.; D’Addezio, J.M.; Smith, S. The Effect of Spatially Correlated Errors on Sea Surface Height Retrieval from SWOT Altimetry. Remote Sens. 2023, 15, 4277. http://hdl.handle.net/10919/116251 https://doi.org/10.3390/rs15174277 Creative Commons Attribution 4.0 International http://creativecommons.org/licenses/by/4.0/ swath altimetry error covariance data assimilation Article - Refereed Text 2023 ftvirginiatec https://doi.org/10.3390/rs15174277 2024-06-25T14:21:07Z The upcoming technology of wide-swath altimetry from space will enable monitoring the ocean surface at 45 times better spatial resolution and 23 times better accuracy than traditional nadir altimeters. This development will provide a chance to directly observe submesoscale sea surface height (SSH) variations that have a typical magnitude of a few centimeters. Taking full advantage of this opportunity requires correct treatment of the correlated SSH errors caused by uncertainties in environmental conditions beneath the satellite and in the geometry and orientation of the on-board interferometer. These observation errors are highly correlated both along and across the surface swath scanned by the satellite, and this presents a significant challenge for accurate processing. In particular, the SWOT precision matrix has off-diagonal elements that are too numerous to allow standard approaches to remain tractable. In this study, we explore the utility of a block-diagonal approximation to the SWOT precision matrix in order to reconstruct SSH variability in the region east of Greenland. An extensive set of 2dVar assimilation experiments demonstrates that the sparse approximation proposed for the precision matrix provides accurate SSH retrievals when the background-to-observation error ratio does not exceed 3 and significant wave height is below 2.5 m. We also quantify the range of and significant wave heights over which the retrieval accuracy of the exact spatially correlated SWOT error model will outperform the uncorrelated model. In particular, the estimated range is found to be substantially wider ( <semantics> < 10 </semantics> with significant wave heights below 810 m), indicating the potential benefits of further improving the accuracy of approximations for the SWOT precision matrix. Published version Article in Journal/Newspaper Greenland VTechWorks (VirginiaTech) Remote Sensing 15 17 4277 |
institution |
Open Polar |
collection |
VTechWorks (VirginiaTech) |
op_collection_id |
ftvirginiatec |
language |
English |
topic |
swath altimetry error covariance data assimilation |
spellingShingle |
swath altimetry error covariance data assimilation Yaremchuk, Max Beattie, Christopher Panteleev, Gleb D’Addezio, Joseph M. Smith, Scott The Effect of Spatially Correlated Errors on Sea Surface Height Retrieval from SWOT Altimetry |
topic_facet |
swath altimetry error covariance data assimilation |
description |
The upcoming technology of wide-swath altimetry from space will enable monitoring the ocean surface at 45 times better spatial resolution and 23 times better accuracy than traditional nadir altimeters. This development will provide a chance to directly observe submesoscale sea surface height (SSH) variations that have a typical magnitude of a few centimeters. Taking full advantage of this opportunity requires correct treatment of the correlated SSH errors caused by uncertainties in environmental conditions beneath the satellite and in the geometry and orientation of the on-board interferometer. These observation errors are highly correlated both along and across the surface swath scanned by the satellite, and this presents a significant challenge for accurate processing. In particular, the SWOT precision matrix has off-diagonal elements that are too numerous to allow standard approaches to remain tractable. In this study, we explore the utility of a block-diagonal approximation to the SWOT precision matrix in order to reconstruct SSH variability in the region east of Greenland. An extensive set of 2dVar assimilation experiments demonstrates that the sparse approximation proposed for the precision matrix provides accurate SSH retrievals when the background-to-observation error ratio does not exceed 3 and significant wave height is below 2.5 m. We also quantify the range of and significant wave heights over which the retrieval accuracy of the exact spatially correlated SWOT error model will outperform the uncorrelated model. In particular, the estimated range is found to be substantially wider ( <semantics> < 10 </semantics> with significant wave heights below 810 m), indicating the potential benefits of further improving the accuracy of approximations for the SWOT precision matrix. Published version |
format |
Article in Journal/Newspaper |
author |
Yaremchuk, Max Beattie, Christopher Panteleev, Gleb D’Addezio, Joseph M. Smith, Scott |
author_facet |
Yaremchuk, Max Beattie, Christopher Panteleev, Gleb D’Addezio, Joseph M. Smith, Scott |
author_sort |
Yaremchuk, Max |
title |
The Effect of Spatially Correlated Errors on Sea Surface Height Retrieval from SWOT Altimetry |
title_short |
The Effect of Spatially Correlated Errors on Sea Surface Height Retrieval from SWOT Altimetry |
title_full |
The Effect of Spatially Correlated Errors on Sea Surface Height Retrieval from SWOT Altimetry |
title_fullStr |
The Effect of Spatially Correlated Errors on Sea Surface Height Retrieval from SWOT Altimetry |
title_full_unstemmed |
The Effect of Spatially Correlated Errors on Sea Surface Height Retrieval from SWOT Altimetry |
title_sort |
effect of spatially correlated errors on sea surface height retrieval from swot altimetry |
publisher |
MDPI |
publishDate |
2023 |
url |
http://hdl.handle.net/10919/116251 https://doi.org/10.3390/rs15174277 |
genre |
Greenland |
genre_facet |
Greenland |
op_relation |
Yaremchuk, M.; Beattie, C.; Panteleev, G.; D’Addezio, J.M.; Smith, S. The Effect of Spatially Correlated Errors on Sea Surface Height Retrieval from SWOT Altimetry. Remote Sens. 2023, 15, 4277. http://hdl.handle.net/10919/116251 https://doi.org/10.3390/rs15174277 |
op_rights |
Creative Commons Attribution 4.0 International http://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.3390/rs15174277 |
container_title |
Remote Sensing |
container_volume |
15 |
container_issue |
17 |
container_start_page |
4277 |
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1810447680884703232 |