scholarly journals Surf and Swash Dynamics on Low Tide Terrace Beaches

Coasts ◽  
2021 ◽  
Vol 1 (1) ◽  
pp. 73-89
Author(s):  
Ivana M. Mingo ◽  
Rafael Almar ◽  
Laurent Lacaze
Keyword(s):  
Energy Dissipation ◽  
Surf Zone ◽  
Wave Climate ◽  
Swash Zone ◽  
Dean Number ◽  
Incoming Wave ◽  
Common View ◽  
Wave Energy Dissipation ◽  
Equilibrium Beach Profile ◽  
High Dynamics

Low tide terrace (LLT) beaches are characterised by a moderately steep beach face and a flat shallow terrace influencing the local hydro-morphodynamics during low tide. The upper beachface slope (β) and the terrace width (Lt) are the main morphological parameters that define the shape of LTT cross-shore beach profiles. This work aims at better understanding the behaviour of β and Lt and their link with the incoming wave forcing. For this purpose, our results are based on 3.5 years times series of daily beach profiles and wave conditions surveys at two different microtidal LTT beaches with similar sediments size but different wave climate, one at Nha Trang (Vietnam) and the other one at Grand Popo (Benin). While they look similar, two contrasting behaviour were linked to two sub-types of LTT regimes: the first one is surf regulated beaches (SRB) where the swash zone is highly regulated by the surf zone wave energy dissipation on the terrace, and the second is swash regulated beaches (SwRB) acting in more reflective regime where the terrace is not active and the energy dissipation is mainly produced in the swash zone, the terrace becomes a consequences of the high dynamics in the swash zone. Finally, extending the common view of an equilibrium beach profile as a power law of the cross-shore distance, the ability of a simple parametrized cubic function model with the Dean number as unique control parameters is proposed and discussed. This simple model can be used for the understanding of LLT environments but it can not be extended to the whole beach spectrum.

Estimating wave energy dissipation in the surf zone using thermal infrared imagery

2015 ◽  
Vol 120 (6) ◽  
pp. 3937-3957 ◽  
Author(s):  
Roxanne J. Carini ◽  
C. Chris Chickadel ◽  
Andrew T. Jessup ◽  
Jim Thomson
Keyword(s):  
Energy Dissipation ◽  
Wave Energy ◽  
Surf Zone ◽  
Thermal Infrared ◽  
Infrared Imagery ◽  
Wave Energy Dissipation ◽  
Thermal Infrared Imagery

scholarly journals ABOUT THE ENERGY DISSIPATION OVER BARRED BEACH

1988 ◽  
Vol 1 (21) ◽  
pp. 20
Author(s):  
Johannes Oelerich ◽  
Hans-Henning Dette
Keyword(s):  
Stochastic Process ◽  
Energy Dissipation ◽  
Surf Zone ◽  
Field Measurements ◽  
The West ◽  
Wave Energy Dissipation ◽  
Wave Flume ◽  
Moderate Energy ◽  
Empirical Approaches ◽  
Spilling Breaker

Since wave energy dissipation in the surf zone is a stochastic process closed mathematical formulations cannot be expected. The dissipation was computed using several analytical and/or empirical approaches and compared with prototype measurements in the Big Wave Flume (GWK) in Hannover as well as with field measurements from the west coast, of the Island of Sylt/North Sea. Generally good agreements were found for moderate energy dissipation conditions (spilling-breaker), whereas in the case of plunging breakers, however, the fitting is not solved satisfactory.

scholarly journals Local Wave Energy Dissipation and Morphological Beach Characteristics along a Northernmost Segment of the Polish Coast

2018 ◽  
Vol 65 (2) ◽  
pp. 91-108
Author(s):  
Grzegorz Różyński
Keyword(s):  
Energy Dissipation ◽  
Wave Energy ◽  
Wave Breaking ◽  
Beach Profile ◽  
Sedimentary Characteristics ◽  
Wave Energy Dissipation ◽  
Equilibrium Beach Profile ◽  
Local Wave ◽  
Processing Techniques ◽  
Signal Processing Techniques

AbstractThis paper analyses cross-shore bathymetric profiles between Władysławowo (km 125 of the Polish coastal chainage) and Lake Sarbsko (km 174) done in 2005 and 2011. Spaced every 500 m, they cover beach topography from dune/cliff crests to a seabed depth of about 15 m. They were decomposed by signal processing techniques to extract the monotonic component of beach topography and to perform a straightforward assessment of wave energy dissipation rates. Three characteristic dissipation patterns were identified: one associated with large nearshore bars and 2–3 zones of wave breaking; a second, to which the equilibrium beach profile concept can be applied; and a third, characterized by mixed behaviour. An attempt was then made to interpret these types of wave energy dissipation in terms of local coastal morphological features and the underlying sedimentary characteristics.

Wave Height Variation Across Surf Zone of Bar Type Profile

2009 ◽  
Author(s):  
Tai-Wen Hsu ◽  
Kun-Sian Lai
Keyword(s):  
Energy Dissipation ◽  
Wave Height ◽  
Analytical Solutions ◽  
Wave Energy ◽  
Hydraulic Jump ◽  
Surf Zone ◽  
Wave Transformation ◽  
Height Variation ◽  
Wave Energy Dissipation ◽  
Theoretical Results

Analytical solutions for wave height decay due to shoaling and breaking on a bar type profile are presented. A macroscopic analogy between an idealized surf zone and a hydraulic jump are incorporated in the theory to account for wave transformation and energy dissipation in the surf zone. The theoretical results are fairly compared with laboratory observations. Key parameters that influence wave energy dissipation in the surf zone are investigated.

scholarly journals Sea spray aerosol and wave energy dissipation in the surf zone

2007 ◽  
Author(s):  
M. J. Francius ◽  
J. Piazolla ◽  
P. Forget ◽  
O. Le Calve ◽  
J. Kusmierczyk-Michulec
Keyword(s):  
Energy Dissipation ◽  
Wave Energy ◽  
Surf Zone ◽  
Sea Spray ◽  
Wave Energy Dissipation ◽  
Sea Spray Aerosol

scholarly journals FIELD CALCULATIONS OF WAVE ENERGY DISSIPATION AND RELATED BEACH PROFILE

1988 ◽  
Vol 1 (21) ◽  
pp. 135
Author(s):  
James R. Tallent ◽  
Takao Yamashita ◽  
Yoshito Tsuchiya
Keyword(s):  
Energy Dissipation ◽  
Wave Energy ◽  
Field Data ◽  
Surf Zone ◽  
Wave Theory ◽  
Nonlinearity Parameter ◽  
Engineering Project ◽  
Wave Energy Dissipation ◽  
Dissipation Model ◽  
Zone Field

The process by which wave energy dissipates across the surf zone and its affect on the bed profile is, of course, a topic of immediate concern and debate. Various concepts of the wave energy dissipation process have been modeled, however, additional research is needed before confidence can be placed in a particular calculation scheme. In addition to the problems associated with proper model derivation a method of application and result interpretation of actual surf zone field data must be devised and understood. This is, of course, prerequisite to any realistic use of a wave energy dissipation model in an engineering project. The following study was therefore conducted in order to examine the applicability of surf zone field data to wave energy dissipation models and to investigate the bed profile relationship. Two wave energy dissipation models were selected for comparison in this study, the 'Undertow Model'(UM) which is based on the conservation of wave energy flux across the surf zone (3), and the 'Turbulent Bore Model'(TBM) which is based on hydraulic jump theory (2). Individual waves were identified in the wave record by employing the zero up-crossing method, and wave energy calculations were based on small amplitude wave theory, Svendsen's nonlinearity parameter Bo (4), and the 1/3 Significant Wave classification.

scholarly journals A NUMERICAL MODEL OF WAVE DEFORMATION IN SURF ZONE

1988 ◽  
Vol 1 (21) ◽  
pp. 41 ◽  
Author(s):  
Akira Watanabe ◽  
Mohammad Dibajnia
Keyword(s):  
Energy Dissipation ◽  
Numerical Model ◽  
Potential Energy ◽  
Wave Height ◽  
Wave Energy ◽  
Surf Zone ◽  
Time Dependent ◽  
Wave Energy Dissipation ◽  
Wave Deformation

A numerical model is presented for nearshore wave deformation due to shoaling and breaking, and to decay and recovery in the surf zone. The model is based on a set of time-dependent mild slope equations including a term of wave energy dissipation caused by breaking. Its applicability is demonstrated by comparisons between the computations and the measurements of cross-shore distributions of the wave height and potential energy over typical beach configurations.

scholarly journals A Coupled Hydrodynamic-Equilibrium Type Beach Profile Evolution Model

2021 ◽  
Vol 9 (4) ◽  
pp. 353
Author(s):  
Florent Birrien ◽  
Tom Baldock
Keyword(s):  
Sediment Transport ◽  
Surf Zone ◽  
Wave Climate ◽  
Transformation Model ◽  
Wave Transformation ◽  
Zone Model ◽  
Beach Profile ◽  
Model Concept ◽  
Equilibrium Beach Profile ◽  
The Cross

An equilibrium beach profile model is developed and coupled with a parametric hydrodynamic model to provide feedback between the evolving morphology and the hydrodynamics. The model is compared to laboratory beach profiles evolving toward equilibrium conditions under constant forcing. The equilibrium model follows the classical approach but uses the bulk sediment transport as the governing model parameter. This approach is coupled with empirically derived and normalised sediment transport functions and a parametric surf zone wave transformation model. The dissipation predicted by the surf zone model controls the cross-shore position of the maxima in the sediment transport functions and hence the cross-shore evolution of the beach profile. Realistic beach profile shapes are generated for both erosive (barred) and accretive (bermed) beach profiles, and predictions of bar and berm position are satisfactory. With more complex normalised sediment transport functions, the model can be applied to conditions with a cyclical wave climate. However, the model concept is better associated with erosive wave conditions and further work is required to improve the link between the modelled dissipation and local transport for accretive conditions.

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