Long Term Morphological Modelling

Abstract

A morphological modelling concept for long term nearshore morphology is proposed and examples of its application are presented and discussed. The model concept combines parameterised representations of the cross-shore morphology, with a 2DH area model for waves, currents and sediment transport in the surf zone. Two parameterization schemes are tested for two different morphological phenomena: 1) Shoreline changes due to the presence of coastal structures and 2) alongshore migration of a nearshore nourishment and a bar by-passing a harbour. In the case of the shoreline evolution calculations, a concept often used in one-line modelling of cross-shore shifting of an otherwise constant shape cross-shore profile is applied for the case of a groyne and a detached breakwater. In the case of alongshore bar/nourishment migration an alternative parameterization is adopted. All examples are presented, analysed and discussed with respect to the question of realistic representation, time scale and general applicability of the model concept.

Sustainable beach design for Raf Raf, Tunisia

“…The model builds on the area model with a dynamic coupling of a hydrodynamics module, a spectral wave module and a sand transport is module (non-cohesive sediment). Morphological evolution is however constrained by forcing the bed update in the model in terms of seaward or landward movement of the shoreline in response to accretion or erosion as described in (KAERGAARD & FREDSOE 2013;KRISTENSEN et al, 2010). Previous application of the model includes determination of shoreline response to breakwaters, (DRØNEN et al, 2011;KAERGAARD et al, 2014) and development due to mega nourishment, (KAERGAARD & DRØNEN, 2015).…”

Evaluation of Nourishment Schemes Based on Long-Term Morphological Modeling

“…An in-depth description of the hybrid modeling concept is given in Kristensen et al (2010); in the following, only a brief description is given. The hybrid morphological modeling concept uses detailed two-dimensional area models to describe the wave, current and sediment transport fields.…”

“…The recently developed long-term morphological modeling concept proposed in Kristensen et al (2010) is used in order to evaluate the impact of nourishment schemes. The concept tries to bridge the gap between existing detailed two-dimensional morphological models and simple one-line models for the coastline evolution and hence is referred to as 1-D hybrid modeling.…”

The Expansion of the Port of Hanstholm - The Future Conditions for a Bypass Harbour

“…For comparison of methods supplementary investigations were conducted by use of a dynamic research simulation model using the hybrid model concept (Kristensen et al 2010 and2013). The model simulates the morphological evolution with constraints on the bed evolution: morphological evolution is only simulated in the depositional area in front of the main northern breakwater and the deposition is with a fixed slope.…”