Deriving High Spatial-Resolution Coastal Topography From Sub-meter Satellite Stereo Imagery

Luís Pedro Almeida, Rafael Almar, Erwin W. J. Bergsma, Etienne Berthier, Paulo Baptista, Erwan Garel, Olusegun A. Dada and Bruna Alves

High spatial resolution coastal Digital Elevation Models (DEMs) are crucial to assess coastal vulnerability and hazards such as beach erosion, sedimentation, or inundation due to storm surges and sea level rise. This paper explores the possibility to use high spatial-resolution Pleiades (pixel size = 0.7 m) stereoscopic satellite imagery to retrieve a DEM on sandy coastline. A 40-km coastal stretch in the Southwest of France was selected as a pilot-site to compare topographic measurements obtained from Pleiades satellite imagery, Real Time Kinematic GPS (RTK-GPS) and airborne Light Detection and Ranging System (LiDAR). The derived 2-m Pleiades DEM shows an overall good agreement with concurrent methods (RTK-GPS and LiDAR; correlation coefficient of 0.9), with a vertical Root Mean Squared Error (RMS error) that ranges from 0.35 to 0.48 m, after absolute coregistration to the LiDAR dataset. The largest errors (RMS error > 0.5 m) occurred in the steep dune faces, particularly at shadowed areas. This work shows that DEMs derived from sub-meter satellite imagery capture local morphological features (e.g., berm or dune shape) on a sandy beach, over a large spatial domain.
Keywords: Pleiades; photogrammetry; LiDAR; RTK-GPS; beach topography

 

https://www.mdpi.com/2072-4292/11/5/590/html

O CIMA é financiado pela Fundação para a Ciência e a Tecnologia (FCT) através da referência UIDP/00350/2020, com sede no Campus Universitário de Gambelas, Edifício 7,  8005-139 FARO PORTUGAL. Tel: 351 289 244 434, 351 289 800 100; E-mail: cima@ualg.pt (+ info)
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O CIMA é financiado pela Fundação para a Ciência e a Tecnologia (FCT) através da referência UIDP/00350/2020, com sede no Campus Universitário de Gambelas, Edifício 7,  8005-139 FARO PORTUGAL. Tel: 351 289 244 434, 351 289 800 100; E-mail: cima@ualg.pt
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