Near‐Bed Sediment Transport Processes During Onshore Bar Migration in Large‐Scale Experiments: Comparison With Offshore Bar Migration

Autor: Florian Grossmann, David Hurther, Joep van der Zanden, Agustín Sánchez‐Arcilla, José M. Alsina
Přispěvatelé: Universitat Politècnica de Catalunya [Barcelona] (UPC), Laboratoire des Écoulements Géophysiques et Industriels [Grenoble] (LEGI), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), Maritime Research Institute Netherlands (MARIN), European Project: 654110,H2020,H2020-INFRAIA-2014-2015,HYDRALAB-PLUS(2015), Universitat Politècnica de Catalunya. Doctorat en Ciències del Mar, Universitat Politècnica de Catalunya. Departament d'Enginyeria Civil i Ambiental, Universitat Politècnica de Catalunya. Departament d’Enginyeria Gràfica i de Disseny, Universitat Politècnica de Catalunya. LIM/UPC - Laboratori d'Enginyeria Marítima
Jazyk: angličtina
Rok vydání: 2023
Předmět:
Zdroj: Journal of Geophysical Research. Oceans
Journal of Geophysical Research. Oceans, 2023, 128 (3), pp.e2022JC018998. ⟨10.1029/2022jc018998⟩
ISSN: 2169-9275
2169-9291
Popis: Detailed information on nearshore sediment transport processes during onshore bar migration were obtained from large-scale laboratory experiments with bichromatic wave groups on a relatively steep initial beach slope (1:15). Detailed measurements of velocity and sand concentration near the bed from shoaling up to the outer breaking zone including suspended sediment and sheet flow transport are presented. The analysis focuses on onshore migration under an accretive wave condition but comparison to an erosive condition highlights important differences. Decomposition shows that total transport mainly results from a balance of short wave-related, bedload onshore transport and current-related, suspended offshore transport. When comparing the accretive to the more energetic erosive condition, the balance shifts toward onshore transport, and onshore migration, because the short wave-related transport does not decrease as much as the current-related transport. This is related to the effects of skewness and asymmetry combined with less sediment suspension in the water column and undertow magnitude under the accretive condition. Transports from streaming in the wave boundary layer and from infragravity waves become visible but only play a subordinate role. Identified priorities for numerical model development include parametrization of wave nonlinearity effects and better description of wave breaking and its influences on sediment suspension. We thank Dr. Troels Aagaard and another, anonymous reviewer for their valuable comments which helped to improve the manuscript. The experiments described in this work were funded by the European Community's Horizon 2020 Programme through the grant to the budget of the Integrated Infrastructure Initiative HYDRALAB+, Contract 654110, and were conducted as part of the transnational access project RESIST. FG acknowledges funding from the Agency for Management of University and Research Grants (AGAUR). DH acknowledges funding from the French DGA funded ANR ASTRID Maturation project MESURE (ANR-16-ASMA-0005-01). JA acknowledges funding from the Serra Húnter Programme (SHP). We wish to thank fellow RESIST researchers and the CIEM staff (Joaquim Sospedra, Oscar Galego, Dr. Andrea Marzeddu, and Dr. Iván Cáceres) for their contributions to the experiments.
Databáze: OpenAIRE
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