Automated High-Resolution Bathymetry from Sentinel-1 SAR Images in Deeper Nearshore Coastal Waters in Eastern Florida

Synthetic aperture radar (SAR) imagers are active microwave sensors that could overcome many challenges of passive optical bathymetry inversion, yet their capacity to yield accurate high-resolution bathymetric mapping is not studied sufficiently. In this study, we evaluate the feasibility of applyin...

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Main Authors: Sanduni D. Mudiyanselage, Ben Wilkinson, Amr Abd-Elrahman
Format: Article
Language:English
Published: MDPI AG 2023-12-01
Series:Remote Sensing
Subjects:
Online Access:https://www.mdpi.com/2072-4292/16/1/1
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author Sanduni D. Mudiyanselage
Ben Wilkinson
Amr Abd-Elrahman
author_facet Sanduni D. Mudiyanselage
Ben Wilkinson
Amr Abd-Elrahman
author_sort Sanduni D. Mudiyanselage
collection DOAJ
description Synthetic aperture radar (SAR) imagers are active microwave sensors that could overcome many challenges of passive optical bathymetry inversion, yet their capacity to yield accurate high-resolution bathymetric mapping is not studied sufficiently. In this study, we evaluate the feasibility of applying fast Fourier transform (FFT) to SAR data in coastal nearshore bathymetry derivation in Florida’s coastal waters. The study aims to develop a robust SAR bathymetry inversion framework across extensive spatial scales to address the dearth of bathymetric data in deeper nearshore coastal regions. By leveraging the Sentinel-1 datasets as a rich source of training data, our method yields high-resolution and accurate depth extraction up to 80 m. A comprehensive workflow to determine both the wavelength and peak wave period is associated with the proposed automated model compilation. A novel contour geometry-based spectral analysis technique for wavelength retrieval is presented that enables an efficient and scalable SAR bathymetry model. Multi-date SAR images were used to assess the robustness of the proposed depth-retrieval model. An accuracy assessment against the GMRT data demonstrated the high efficacy of the proposed approach, achieving a coefficient of determination (<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msup><mi>R</mi><mn>2</mn></msup></mrow></semantics></math></inline-formula>) above 0.95, a root-mean-square error (RMSE) of 1.56–10.20 m, and relative errors of 3.56–11.08% in automatically extracting the underwater terrain at every 50 m interval. A sensitivity analysis was conducted to estimate the uncertainty associated with our method. Overall, this study highlights the potential of SAR technology to produce updated, cost-effective, and accurate bathymetry maps of high resolution and to fill bathymetric data gaps worldwide. The code and datasets are made publicly available.
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spelling doaj.art-dbb805baf73a4ea495b737e408fcc2a92024-01-10T15:07:03ZengMDPI AGRemote Sensing2072-42922023-12-01161110.3390/rs16010001Automated High-Resolution Bathymetry from Sentinel-1 SAR Images in Deeper Nearshore Coastal Waters in Eastern FloridaSanduni D. Mudiyanselage0Ben Wilkinson1Amr Abd-Elrahman2School of Forest Fisheries and Geomatics Sciences, University of Florida, Gainesville, FL 32611, USASchool of Forest Fisheries and Geomatics Sciences, University of Florida, Gainesville, FL 32611, USASchool of Forest Fisheries and Geomatics Sciences, University of Florida, Gainesville, FL 32611, USASynthetic aperture radar (SAR) imagers are active microwave sensors that could overcome many challenges of passive optical bathymetry inversion, yet their capacity to yield accurate high-resolution bathymetric mapping is not studied sufficiently. In this study, we evaluate the feasibility of applying fast Fourier transform (FFT) to SAR data in coastal nearshore bathymetry derivation in Florida’s coastal waters. The study aims to develop a robust SAR bathymetry inversion framework across extensive spatial scales to address the dearth of bathymetric data in deeper nearshore coastal regions. By leveraging the Sentinel-1 datasets as a rich source of training data, our method yields high-resolution and accurate depth extraction up to 80 m. A comprehensive workflow to determine both the wavelength and peak wave period is associated with the proposed automated model compilation. A novel contour geometry-based spectral analysis technique for wavelength retrieval is presented that enables an efficient and scalable SAR bathymetry model. Multi-date SAR images were used to assess the robustness of the proposed depth-retrieval model. An accuracy assessment against the GMRT data demonstrated the high efficacy of the proposed approach, achieving a coefficient of determination (<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msup><mi>R</mi><mn>2</mn></msup></mrow></semantics></math></inline-formula>) above 0.95, a root-mean-square error (RMSE) of 1.56–10.20 m, and relative errors of 3.56–11.08% in automatically extracting the underwater terrain at every 50 m interval. A sensitivity analysis was conducted to estimate the uncertainty associated with our method. Overall, this study highlights the potential of SAR technology to produce updated, cost-effective, and accurate bathymetry maps of high resolution and to fill bathymetric data gaps worldwide. The code and datasets are made publicly available.https://www.mdpi.com/2072-4292/16/1/1satellite-derived bathymetry (SDB)synthetic aperture radar (SAR)Sentinel-1swell wavesfast Fourier transform (FFT)dispersion relation
spellingShingle Sanduni D. Mudiyanselage
Ben Wilkinson
Amr Abd-Elrahman
Automated High-Resolution Bathymetry from Sentinel-1 SAR Images in Deeper Nearshore Coastal Waters in Eastern Florida
Remote Sensing
satellite-derived bathymetry (SDB)
synthetic aperture radar (SAR)
Sentinel-1
swell waves
fast Fourier transform (FFT)
dispersion relation
title Automated High-Resolution Bathymetry from Sentinel-1 SAR Images in Deeper Nearshore Coastal Waters in Eastern Florida
title_full Automated High-Resolution Bathymetry from Sentinel-1 SAR Images in Deeper Nearshore Coastal Waters in Eastern Florida
title_fullStr Automated High-Resolution Bathymetry from Sentinel-1 SAR Images in Deeper Nearshore Coastal Waters in Eastern Florida
title_full_unstemmed Automated High-Resolution Bathymetry from Sentinel-1 SAR Images in Deeper Nearshore Coastal Waters in Eastern Florida
title_short Automated High-Resolution Bathymetry from Sentinel-1 SAR Images in Deeper Nearshore Coastal Waters in Eastern Florida
title_sort automated high resolution bathymetry from sentinel 1 sar images in deeper nearshore coastal waters in eastern florida
topic satellite-derived bathymetry (SDB)
synthetic aperture radar (SAR)
Sentinel-1
swell waves
fast Fourier transform (FFT)
dispersion relation
url https://www.mdpi.com/2072-4292/16/1/1
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AT amrabdelrahman automatedhighresolutionbathymetryfromsentinel1sarimagesindeepernearshorecoastalwatersineasternflorida