Satellite-derived equilibrium shoreline modelling at a high-energy meso-macrotidal beach - BRGM - Bureau de recherches géologiques et minières Accéder directement au contenu
Article Dans Une Revue Coastal Engineering Année : 2024

Satellite-derived equilibrium shoreline modelling at a high-energy meso-macrotidal beach

Résumé

Modelling and predicting the future of sandy shorelines is a key challenge in coastal research and is critical for sustainable coastal management. However, currently the most skillful shoreline models strongly rely on data to calibrate the free parameters, and are thus restricted to a few well monitored sites in the world. Here we address the challenges and opportunities offered by optical satellite imagery to provide useful information for equilibrium shoreline model calibration on cross-shore transport dominated sites. We focus on Truc Vert beach, southwest France, where previous work showed good equilibrium model skill to reproduce shoreline change from the time scales of hours (storms) to decades. Satellite derived waterlines are extracted over 11 years (2009–2020) and further transformed into satellite derived shorelines (SDS) with different water level corrections (e.g. tide and/or run up) and varying alongshore averaging lengths, and thus different uncertainties, in order to test model performance. Successively the timeseries duration and sampling frequency required for model calibration were also investigated. The model calibrated using the SDS data showed similar skill as the model calibrated using in-situ alongshore averaged shoreline positions, even for the uncorrected SDS dataset which Root Mean Square Error (RMSE) are approximately 30 m. Alongshore averaging was found to be the only necessary processing of the SDS data while any other site-specific corrections did not significantly improve model skill. Finally to further investigate the effect of sampling frequency and noise in the dataset we performed an analysis using a synthetic shoreline. Our results suggest that the effect of noise is negligible as long as the sampling frequency remains high (dt 30 days). Pending further validation, results show the strong potential of using uncorrected SDS dataset for shoreline model calibration at cross-shore transport dominated sandy coasts.
Fichier principal
Vignette du fichier
1-s2.0-S037838392400084X-main.pdf (27.49 Mo) Télécharger le fichier
Origine Fichiers produits par l'(les) auteur(s)

Dates et versions

hal-04573878 , version 1 (13-05-2024)

Identifiants

Citer

Georgios Azorakos, Bruno Castelle, Vincent Marieu, Déborah Idier. Satellite-derived equilibrium shoreline modelling at a high-energy meso-macrotidal beach. Coastal Engineering, 2024, pp.104536. ⟨10.1016/j.coastaleng.2024.104536⟩. ⟨hal-04573878⟩
51 Consultations
10 Téléchargements

Altmetric

Partager

Gmail Mastodon Facebook X LinkedIn More