Part C | 28.4
630 Part C Coastal Design
Models such as Delft3D and SWAN nowadays
have many algorithms describing effects of vegetation
on wave dissipation, flow resistance, and trapping of
sediments by vegetation and recently [28.90], generic
vegetation succession formulations were implemented,
which provides a toolbox to explore these complex interactions.
28.4.3 Dune Modeling
Aeolian transport models can be a valuable addition
to hydrodynamic models to describe the long-term
interaction between land and water. In a recent paper [28.91] present the application of an aeolian transport model [28.92, 93] as a tool for the evolution of
coastal nourishments and dunes. The model was originally developed to describe important features and
dynamics of typical desert dunes and was modified to
apply to sandy beaches and coastal nourishments. This
is expected to be the start of an important line of research as with the increase of large-scale nourishments
natural dune-growth processes are being restored and
need to be considered when trying to predict the longterm evolution of such nourishments.
28.4.4 Coral Reefs
A subject receiving increasing attention is the role
coral reefs play in protecting and building up coastal
environments. Coral reefs are different from other hardprotection structures in that they are incredibly rough
and thereby dissipate wave energy very effectively; they
also generate sediment and thereby, in a healthy situation, can keep up with sea-level rise. Modeling of the
hydrodynamics of coral reef systems has got increasing
attention in the last decade; a thorough review and new
insights into the importance and modeling of infragravity waves on such systems are provided in [28.94]. The
important problem on how island and low-lying coastal
communities protected by reefs can adapt to climate
change and sea-level rise will need much attention in
years to come; see for instance [28.95].
28.4.5 Modeling Stratigraphy
Morphodynamic models are able to reproduce realistic
morphological patterns. By including different classes
of sediment and adding a model for bed composition
administration, they are also able to reproduce stratification in the bed. Depositional layers of fine sediments
can alternate with coarse sediment layers depending on
hydrodynamic conditions in the water column and variations in sediment supply. Long-term ( centuries to
millennia) simulations may thus reproduce stratification characteristics, for instance in a reservoir or river
delta [28.96, 97].
This information is of particular interest to geologists. Morphodynamic models offer a tool to explain
what processes could have caused certain observed
stratification features. Stratification models could also
be used the other way round. Once it is known what
prevailing hydrodynamic conditions in a certain domain
were, the stratification model may reproduce stratification characteristics and permeability parameters. These
data are of particular interest to investigating groundwater flows or to determining in a better way the placing
of wells or bore holes for the oil industry.
28.4.6 Morphological Modeling
of Tsunami Deposits
There is a wide body of research related to the analysis of historical tsunami deposits in order to obtain
information on the frequency and strength of tsunamis.
In [28.98], a simple model is proposed to link the
tsunami flow speed to tsunami deposits; Goto and Imamura [28.99] consider the requirements of numerical
models capable of modeling transport of sediment and
large boulders during tsunamis; in [28.100], detailed
morphodynamic modeling of the 2004 Indian Ocean
Tsunami is carried out and the damping effect of vegetation is considered, using the Delft3D model; the
same system is used in an extensive 2DV analysis
of flow patterns, turbulence, sediment concentration,
and erosion/deposition for different cross-shore profiles [28.73]. In an extensive hindcast of the tsunami
at Bandar Aceh, Li et al. [28.101] apply a two-way
coupled system of nested models to simulate both
the generation of the tsunami waves and the propagation toward the area of interest; for the finest grid
where morphology changes are important they apply
the XBeach model incorporated into their COMCOT–
SED system. They found that the model presented in
the paper was capable of simulating extreme tsunami
events (tsunami wave height in the order of 30 m) over
a large domain, that the thickness of tsunami deposits
could be quantitatively simulated and that therefore
forward models of tsunami sediment transport can be
a promising tool to help tsunami geologists understand
tsunami deposits.
630 Part C Coastal Design
Models such as Delft3D and SWAN nowadays
have many algorithms describing effects of vegetation
on wave dissipation, flow resistance, and trapping of
sediments by vegetation and recently [28.90], generic
vegetation succession formulations were implemented,
which provides a toolbox to explore these complex interactions.
28.4.3 Dune Modeling
Aeolian transport models can be a valuable addition
to hydrodynamic models to describe the long-term
interaction between land and water. In a recent paper [28.91] present the application of an aeolian transport model [28.92, 93] as a tool for the evolution of
coastal nourishments and dunes. The model was originally developed to describe important features and
dynamics of typical desert dunes and was modified to
apply to sandy beaches and coastal nourishments. This
is expected to be the start of an important line of research as with the increase of large-scale nourishments
natural dune-growth processes are being restored and
need to be considered when trying to predict the longterm evolution of such nourishments.
28.4.4 Coral Reefs
A subject receiving increasing attention is the role
coral reefs play in protecting and building up coastal
environments. Coral reefs are different from other hardprotection structures in that they are incredibly rough
and thereby dissipate wave energy very effectively; they
also generate sediment and thereby, in a healthy situation, can keep up with sea-level rise. Modeling of the
hydrodynamics of coral reef systems has got increasing
attention in the last decade; a thorough review and new
insights into the importance and modeling of infragravity waves on such systems are provided in [28.94]. The
important problem on how island and low-lying coastal
communities protected by reefs can adapt to climate
change and sea-level rise will need much attention in
years to come; see for instance [28.95].
28.4.5 Modeling Stratigraphy
Morphodynamic models are able to reproduce realistic
morphological patterns. By including different classes
of sediment and adding a model for bed composition
administration, they are also able to reproduce stratification in the bed. Depositional layers of fine sediments
can alternate with coarse sediment layers depending on
hydrodynamic conditions in the water column and variations in sediment supply. Long-term ( centuries to
millennia) simulations may thus reproduce stratification characteristics, for instance in a reservoir or river
delta [28.96, 97].
This information is of particular interest to geologists. Morphodynamic models offer a tool to explain
what processes could have caused certain observed
stratification features. Stratification models could also
be used the other way round. Once it is known what
prevailing hydrodynamic conditions in a certain domain
were, the stratification model may reproduce stratification characteristics and permeability parameters. These
data are of particular interest to investigating groundwater flows or to determining in a better way the placing
of wells or bore holes for the oil industry.
28.4.6 Morphological Modeling
of Tsunami Deposits
There is a wide body of research related to the analysis of historical tsunami deposits in order to obtain
information on the frequency and strength of tsunamis.
In [28.98], a simple model is proposed to link the
tsunami flow speed to tsunami deposits; Goto and Imamura [28.99] consider the requirements of numerical
models capable of modeling transport of sediment and
large boulders during tsunamis; in [28.100], detailed
morphodynamic modeling of the 2004 Indian Ocean
Tsunami is carried out and the damping effect of vegetation is considered, using the Delft3D model; the
same system is used in an extensive 2DV analysis
of flow patterns, turbulence, sediment concentration,
and erosion/deposition for different cross-shore profiles [28.73]. In an extensive hindcast of the tsunami
at Bandar Aceh, Li et al. [28.101] apply a two-way
coupled system of nested models to simulate both
the generation of the tsunami waves and the propagation toward the area of interest; for the finest grid
where morphology changes are important they apply
the XBeach model incorporated into their COMCOT–
SED system. They found that the model presented in
the paper was capable of simulating extreme tsunami
events (tsunami wave height in the order of 30 m) over
a large domain, that the thickness of tsunami deposits
could be quantitatively simulated and that therefore
forward models of tsunami sediment transport can be
a promising tool to help tsunami geologists understand
tsunami deposits.