SAR Imaging Features of Shallow Water Bathymetry
Purpose. The aim of the article is to study manifestations of the underwater topography features in the northern part of the White Sea in the images made by the spaceborn synthetic aperture radars (SAR) Sentinel-1A, Sentinel-1B. Methods and Results. In the SAR images, the bottom features are reveale...
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Federal State Budget Scientific Institution «Marine Hydrophysical Institute of RAS»
2020
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ftdoajarticles:oai:doaj.org/article:2514c2ed462e479881846cf3833aa0cf 2023-05-15T18:43:55+02:00 SAR Imaging Features of Shallow Water Bathymetry P.D. Pivaev V.N. Kudryavtsev E.A. Balashova B. Chapron 2020-06-01T00:00:00Z https://doi.org/10.22449/1573-160X-2020-3-290-304 https://doaj.org/article/2514c2ed462e479881846cf3833aa0cf EN eng Federal State Budget Scientific Institution «Marine Hydrophysical Institute of RAS» http://physical-oceanography.ru/repository/2020/3/en_202003_06.pdf https://doaj.org/toc/1573-160X doi:10.22449/1573-160X-2020-3-290-304 1573-160X https://doaj.org/article/2514c2ed462e479881846cf3833aa0cf Physical Oceanography, Vol 27, Iss 3, Pp 290-304 (2020) bottom topography sentinel-1 sar wave breaking current divergence Oceanography GC1-1581 article 2020 ftdoajarticles https://doi.org/10.22449/1573-160X-2020-3-290-304 2022-12-31T06:22:39Z Purpose. The aim of the article is to study manifestations of the underwater topography features in the northern part of the White Sea in the images made by the spaceborn synthetic aperture radars (SAR) Sentinel-1A, Sentinel-1B. Methods and Results. In the SAR images, the bottom features are revealed as bright and dark brightness anomalies. The anomalies were observed at the wind speed ranging from 2.6 to 10.8 m/s, and became reverse (bright anomalies turned dark and vice versa), when a tidal current changed its direction. It is shown that the observed SAR imagery contrasts correlate to divergence of a current formed by interaction of a tidal flow with the bottom topography inhomogeneities. The simulated SAR contrasts agree with the observations, and confirm the relation between the observed SAR contrasts and the current divergence. Together with modeling the SAR contrasts, the contribution of different mechanisms to formation of the observed modulations of the normalized radar cross section was qualitatively estimated. The wave breaking effect was especially accentuated. The method for retrieving the underwater bottom topography based on the relationship between the bottom gradient and the SAR imagery contrasts is proposed. Conclusions. Location of the bottom inhomogeneities in the shallow water region on the whole coincides with that of the tidal current divergence and convergence zones, which are observed as brightness anomalies in the SAR images. Breaking of surface waves is the main contributor to the observed SAR contrasts. The bottom topography reconstructed from the SAR contrasts, and the actual one resulted from the bathymetry maps are in good agreement. Some discrepancies are interpreted as possible changes in depth and shape of the bottom topography features induced by action of strong currents and waves. Article in Journal/Newspaper White Sea Directory of Open Access Journals: DOAJ Articles White Sea Physical Oceanography 27 3 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
bottom topography sentinel-1 sar wave breaking current divergence Oceanography GC1-1581 |
spellingShingle |
bottom topography sentinel-1 sar wave breaking current divergence Oceanography GC1-1581 P.D. Pivaev V.N. Kudryavtsev E.A. Balashova B. Chapron SAR Imaging Features of Shallow Water Bathymetry |
topic_facet |
bottom topography sentinel-1 sar wave breaking current divergence Oceanography GC1-1581 |
description |
Purpose. The aim of the article is to study manifestations of the underwater topography features in the northern part of the White Sea in the images made by the spaceborn synthetic aperture radars (SAR) Sentinel-1A, Sentinel-1B. Methods and Results. In the SAR images, the bottom features are revealed as bright and dark brightness anomalies. The anomalies were observed at the wind speed ranging from 2.6 to 10.8 m/s, and became reverse (bright anomalies turned dark and vice versa), when a tidal current changed its direction. It is shown that the observed SAR imagery contrasts correlate to divergence of a current formed by interaction of a tidal flow with the bottom topography inhomogeneities. The simulated SAR contrasts agree with the observations, and confirm the relation between the observed SAR contrasts and the current divergence. Together with modeling the SAR contrasts, the contribution of different mechanisms to formation of the observed modulations of the normalized radar cross section was qualitatively estimated. The wave breaking effect was especially accentuated. The method for retrieving the underwater bottom topography based on the relationship between the bottom gradient and the SAR imagery contrasts is proposed. Conclusions. Location of the bottom inhomogeneities in the shallow water region on the whole coincides with that of the tidal current divergence and convergence zones, which are observed as brightness anomalies in the SAR images. Breaking of surface waves is the main contributor to the observed SAR contrasts. The bottom topography reconstructed from the SAR contrasts, and the actual one resulted from the bathymetry maps are in good agreement. Some discrepancies are interpreted as possible changes in depth and shape of the bottom topography features induced by action of strong currents and waves. |
format |
Article in Journal/Newspaper |
author |
P.D. Pivaev V.N. Kudryavtsev E.A. Balashova B. Chapron |
author_facet |
P.D. Pivaev V.N. Kudryavtsev E.A. Balashova B. Chapron |
author_sort |
P.D. Pivaev |
title |
SAR Imaging Features of Shallow Water Bathymetry |
title_short |
SAR Imaging Features of Shallow Water Bathymetry |
title_full |
SAR Imaging Features of Shallow Water Bathymetry |
title_fullStr |
SAR Imaging Features of Shallow Water Bathymetry |
title_full_unstemmed |
SAR Imaging Features of Shallow Water Bathymetry |
title_sort |
sar imaging features of shallow water bathymetry |
publisher |
Federal State Budget Scientific Institution «Marine Hydrophysical Institute of RAS» |
publishDate |
2020 |
url |
https://doi.org/10.22449/1573-160X-2020-3-290-304 https://doaj.org/article/2514c2ed462e479881846cf3833aa0cf |
geographic |
White Sea |
geographic_facet |
White Sea |
genre |
White Sea |
genre_facet |
White Sea |
op_source |
Physical Oceanography, Vol 27, Iss 3, Pp 290-304 (2020) |
op_relation |
http://physical-oceanography.ru/repository/2020/3/en_202003_06.pdf https://doaj.org/toc/1573-160X doi:10.22449/1573-160X-2020-3-290-304 1573-160X https://doaj.org/article/2514c2ed462e479881846cf3833aa0cf |
op_doi |
https://doi.org/10.22449/1573-160X-2020-3-290-304 |
container_title |
Physical Oceanography |
container_volume |
27 |
container_issue |
3 |
_version_ |
1766234445020397568 |