Effects of Surface Wave Breaking Caused by Internal Solitary Waves in SAR Altimeter: Sentinel-3 Copernicus Products and Advanced New Products
We address surface wave breaking caused by oceanic Internal Solitary Waves (ISWs) and how ISWs are manifested in the SAR altimeter onboard Sentinel-3A and -3B satellites by means of their effects in Significant Wave Height (SWH). Two different regions of the ocean are selected, namely the tropical A...
| Main Authors: | , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2022-01-01
|
| Series: | Remote Sensing |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2072-4292/14/3/587 |
| _version_ | 1797485078760128512 |
|---|---|
| author | Adriana M. Santos-Ferreira José C. B. da Silva Jorge M. Magalhaes Samira Amraoui Thomas Moreau Claire Maraldi François Boy Nicolas Picot Franck Borde |
| author_facet | Adriana M. Santos-Ferreira José C. B. da Silva Jorge M. Magalhaes Samira Amraoui Thomas Moreau Claire Maraldi François Boy Nicolas Picot Franck Borde |
| author_sort | Adriana M. Santos-Ferreira |
| collection | DOAJ |
| description | We address surface wave breaking caused by oceanic Internal Solitary Waves (ISWs) and how ISWs are manifested in the SAR altimeter onboard Sentinel-3A and -3B satellites by means of their effects in Significant Wave Height (SWH). Two different regions of the ocean are selected, namely the tropical Atlantic Ocean off the Amazon shelf and the Banda Sea in the Indian Ocean, where there are scenes of Sentinel-3 OLCI acquired simultaneously with an along-track SAR mode altimeter, which include signatures of large amplitude ISWs. New data of unfocused SAR (UF-SAR 20 Hz) and fully focused SAR (FF-SAR 160 Hz) modes are analyzed, which are retracked in full range and over a reduced range of bins (truncation carried out dynamically ten gates away from the estimated epoch position). At first order, in scales of 1–3 km, a strong decrease in the normalized radar cross section (NRCS) over the rough part of the ISWs is observed followed by a small increase in the smooth part relative to the unperturbed ocean background. A second order ISW signature, in scales of 20 km, is noted: the SWH is attenuated after the passage of an ISW, considering length scales of about 10 km before and after the ISW crest. The SWH signatures are unique in showing that the surface wave energy does not return to its unperturbed level after the passage of an ISW, admittedly because intense meter-scale wave breaking results in surface wave energy dissipation. Furthermore, Sentinel-2 MSI images are analyzed and provide insights into this same phenomenon: white-capping resulting in a radiance increase at all (visible) wavelengths. Modulation of breaking waves owing to ISWs is demonstrated by estimates of the fraction of breaking waves in the presence of internal waves. |
| first_indexed | 2024-03-09T23:13:42Z |
| format | Article |
| id | doaj.art-71e7a22581fc4427b5ba11424bee96dd |
| institution | Directory Open Access Journal |
| issn | 2072-4292 |
| language | English |
| last_indexed | 2024-03-09T23:13:42Z |
| publishDate | 2022-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Remote Sensing |
| spelling | doaj.art-71e7a22581fc4427b5ba11424bee96dd2023-11-23T17:40:11ZengMDPI AGRemote Sensing2072-42922022-01-0114358710.3390/rs14030587Effects of Surface Wave Breaking Caused by Internal Solitary Waves in SAR Altimeter: Sentinel-3 Copernicus Products and Advanced New ProductsAdriana M. Santos-Ferreira0José C. B. da Silva1Jorge M. Magalhaes2Samira Amraoui3Thomas Moreau4Claire Maraldi5François Boy6Nicolas Picot7Franck Borde8Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), Terminal de Cruzeiros de Leixões, Av. General Norton de Matos, s/n, 4450-208 Matosinhos, PortugalDepartment of Geoscience, Environment and Spatial Planning (DGAOT), Faculty of Sciences, University of Porto, Rua do Campo Alegre, s/n, 4169-007 Porto, PortugalInterdisciplinary Centre of Marine and Environmental Research (CIIMAR), Terminal de Cruzeiros de Leixões, Av. General Norton de Matos, s/n, 4450-208 Matosinhos, PortugalCollecte Localisation Satellites (CLS), 11 Rue Hermès, Parc Technologique du Canal, 31520 Ramonville St. Agne, FranceCollecte Localisation Satellites (CLS), 11 Rue Hermès, Parc Technologique du Canal, 31520 Ramonville St. Agne, FranceCentre National d’Études Spatiales (CNES), 18 Avenue Edouard Belin, CEDEX 9, 31401 Toulouse, FranceCentre National d’Études Spatiales (CNES), 18 Avenue Edouard Belin, CEDEX 9, 31401 Toulouse, FranceCentre National d’Études Spatiales (CNES), 18 Avenue Edouard Belin, CEDEX 9, 31401 Toulouse, FranceEuropean Space Agency/European Space Research and Technology Centre (ESA/ESTEC), Keplerlaan, 1, 2201 AZ Noordwijk, The NetherlandsWe address surface wave breaking caused by oceanic Internal Solitary Waves (ISWs) and how ISWs are manifested in the SAR altimeter onboard Sentinel-3A and -3B satellites by means of their effects in Significant Wave Height (SWH). Two different regions of the ocean are selected, namely the tropical Atlantic Ocean off the Amazon shelf and the Banda Sea in the Indian Ocean, where there are scenes of Sentinel-3 OLCI acquired simultaneously with an along-track SAR mode altimeter, which include signatures of large amplitude ISWs. New data of unfocused SAR (UF-SAR 20 Hz) and fully focused SAR (FF-SAR 160 Hz) modes are analyzed, which are retracked in full range and over a reduced range of bins (truncation carried out dynamically ten gates away from the estimated epoch position). At first order, in scales of 1–3 km, a strong decrease in the normalized radar cross section (NRCS) over the rough part of the ISWs is observed followed by a small increase in the smooth part relative to the unperturbed ocean background. A second order ISW signature, in scales of 20 km, is noted: the SWH is attenuated after the passage of an ISW, considering length scales of about 10 km before and after the ISW crest. The SWH signatures are unique in showing that the surface wave energy does not return to its unperturbed level after the passage of an ISW, admittedly because intense meter-scale wave breaking results in surface wave energy dissipation. Furthermore, Sentinel-2 MSI images are analyzed and provide insights into this same phenomenon: white-capping resulting in a radiance increase at all (visible) wavelengths. Modulation of breaking waves owing to ISWs is demonstrated by estimates of the fraction of breaking waves in the presence of internal waves.https://www.mdpi.com/2072-4292/14/3/587internal solitary waves (ISWs)wave breakingdelay-Doppler altimeterradar backscatteraltimetrySAR |
| spellingShingle | Adriana M. Santos-Ferreira José C. B. da Silva Jorge M. Magalhaes Samira Amraoui Thomas Moreau Claire Maraldi François Boy Nicolas Picot Franck Borde Effects of Surface Wave Breaking Caused by Internal Solitary Waves in SAR Altimeter: Sentinel-3 Copernicus Products and Advanced New Products Remote Sensing internal solitary waves (ISWs) wave breaking delay-Doppler altimeter radar backscatter altimetry SAR |
| title | Effects of Surface Wave Breaking Caused by Internal Solitary Waves in SAR Altimeter: Sentinel-3 Copernicus Products and Advanced New Products |
| title_full | Effects of Surface Wave Breaking Caused by Internal Solitary Waves in SAR Altimeter: Sentinel-3 Copernicus Products and Advanced New Products |
| title_fullStr | Effects of Surface Wave Breaking Caused by Internal Solitary Waves in SAR Altimeter: Sentinel-3 Copernicus Products and Advanced New Products |
| title_full_unstemmed | Effects of Surface Wave Breaking Caused by Internal Solitary Waves in SAR Altimeter: Sentinel-3 Copernicus Products and Advanced New Products |
| title_short | Effects of Surface Wave Breaking Caused by Internal Solitary Waves in SAR Altimeter: Sentinel-3 Copernicus Products and Advanced New Products |
| title_sort | effects of surface wave breaking caused by internal solitary waves in sar altimeter sentinel 3 copernicus products and advanced new products |
| topic | internal solitary waves (ISWs) wave breaking delay-Doppler altimeter radar backscatter altimetry SAR |
| url | https://www.mdpi.com/2072-4292/14/3/587 |
| work_keys_str_mv | AT adrianamsantosferreira effectsofsurfacewavebreakingcausedbyinternalsolitarywavesinsaraltimetersentinel3copernicusproductsandadvancednewproducts AT josecbdasilva effectsofsurfacewavebreakingcausedbyinternalsolitarywavesinsaraltimetersentinel3copernicusproductsandadvancednewproducts AT jorgemmagalhaes effectsofsurfacewavebreakingcausedbyinternalsolitarywavesinsaraltimetersentinel3copernicusproductsandadvancednewproducts AT samiraamraoui effectsofsurfacewavebreakingcausedbyinternalsolitarywavesinsaraltimetersentinel3copernicusproductsandadvancednewproducts AT thomasmoreau effectsofsurfacewavebreakingcausedbyinternalsolitarywavesinsaraltimetersentinel3copernicusproductsandadvancednewproducts AT clairemaraldi effectsofsurfacewavebreakingcausedbyinternalsolitarywavesinsaraltimetersentinel3copernicusproductsandadvancednewproducts AT francoisboy effectsofsurfacewavebreakingcausedbyinternalsolitarywavesinsaraltimetersentinel3copernicusproductsandadvancednewproducts AT nicolaspicot effectsofsurfacewavebreakingcausedbyinternalsolitarywavesinsaraltimetersentinel3copernicusproductsandadvancednewproducts AT franckborde effectsofsurfacewavebreakingcausedbyinternalsolitarywavesinsaraltimetersentinel3copernicusproductsandadvancednewproducts |