Diachronic UAV Photogrammetry of a Sandy Beach in Brittany (France) for a Long-Term Coastal Observatory
|Author(s)||Jaud Marion1, Delacourt Christophe2, Le Dantec Nicolas2, 3, Allemand Pascal4, Ammann Jerome2, Grandjean Philippe4, Nouaille Henri2, Prunier Christophe2, Cuq Veronique5, Augereau Emmanuel6, Cocquempot Lucie2, Floc'h France2|
|Affiliation(s)||1 : Univ Bretagne Occidentale, CNRS, Technopole Brest Iroise, IUEM UMS 3113, Rue Dumont Urville, F-29280 Plouzane, France.
2 : Univ Bretagne Occidentale, CNRS, Technopole Brest Iroise, Lab Geosci Oceans UMR 6538, Rue Dumont Urville, F-29280 Plouzane, France.
3 : Cerema Direct Eau Mer & Fleuves, F-60280 Margny Les Compiegne, France.
4 : Univ Claude Bernard Lyon 1, Univ Lyon, Lab Geol Lyon Terre Planetes Environm UMR 5276, ENS Lyon,CNRS, F-69622 Villeurbanne, France.
5 : Univ Bretagne Occidentale, CNRS, Technopole Brest Iroise, IUEM,LETG UMR 6554, Rue Dumont Urville, F-29280 Plouzane, France.
6 : Univ La Reunion, OSU La Reunion, CS 92003, F-97744 St Denis, Reunion, France.
|Source||Isprs International Journal Of Geo-information (2220-9964) (Mdpi), 2019-06 , Vol. 8 , N. 6 , P. 267 (13p.)|
|WOS© Times Cited||6|
|Note||This article belongs to the Special Issue Applications of Photogrammetry for Environmental Research|
|Keyword(s)||UAV, SfM photogrammetry, coastal observatory, beach monitoring|
In the dual context of coastal hazard intensification and the growing number of stakes exposed to these hazards, coastal observatories are in demand to provide a structured framework dedicated to long-term monitoring. This article describes the drone-based photogrammetry monitoring performed since 2006 on Porsmilin Beach (Brittany, France) in the framework of the DYNALIT (Littoral and Coastline Dynamics) observatory, focusing on data quality and the consistency of long-term time series under the influence of multiple technological evolutions: Unmanned Aerial Vehicles (UAV) platforms with the arrival of electric multirotor drones, processing tools with the development of structure-from-motion (SfM) photogrammetry, and operational modes of survey. A study case is presented to show the potential of UAV monitoring to study storm impacts and beach resilience. The relevance of high-accuracy monitoring is also highlighted. With the current method, an accuracy of 3 cm can be achieved on the digital elevation model (DEM) and the orthophotograph. The question of the representativity and frequency of DEM time points is raised.