DUNEX Modeling Waves, Water Levels, Sediment Transport, and Shoreline Change
Large, collaborative field experiments such as DUNEX leverage observations of the coastal ocean made by multiple academic, agency, and NGO teams, providing the opportunity to grasp a broader picture of the forces responsible for coastal change. Despite deployment of many instruments, it’s impossible to measure everything, everywhere, at all times. Numerical models that represent the physical processes of the coastal ocean, such as waves, tides, currents, and sediment transport, allow us to fill in the observational dataset gaps in space or time. Numerical models can also be controlled to investigate specific physical processes to test hypotheses or compare to observations.
Numerical models are composed of a suite of mathematical equations that attempt to completely describe or estimate physical processes. For DUNEX, we will use a numerical model called COAWST to:
1) predict coastal ocean conditions during the experiment to support other scientists and
2) hindcast coastal ocean conditions and morphological changes during past storm events that were measured during the experiment.
Tools and Software
Numerical models that represent the physical processes of the coastal ocean, such as waves, tides, currents, and sediment transport, allow us to fill in the observational dataset gaps in space or time.
COAWST is the Coupled Ocean-Atmosphere-Wave-Sediment Transport modeling system, which links several models together to simulate forces such as waves and tidal currents and the interactions between them. COAWST has been developed at the USGS in collaboration with academic and other agency partners and has been used to study a wide range of interesting coastal ocean problems, such as rip currents, barrier island breaching, and estuarine circulation.
The forecast of coastal ocean conditions provided by COAWST give our USGS team and other DUNEX scientists information to assist with instrument deployments and surveying. It can also provide an initial dataset to compare against field observations or provide context.
After the experiment, we will hindcast particular storm events, or the quiescent periods in between storms, at very high spatial resolution (1-10 m) to investigate physical processes controlling coastal change. For example, wave breaking controls, in part, wave runup on the beach, surf zone circulation and mixing, and sediment transport in the nearshore. In collaboration with scientists collecting field data, we will evaluate and improve the model parameterizations that describe wave evolution in the nearshore. Additionally, we will explore the exchange of sand between the dune, beach, and nearshore, and the various conditions responsible for sand transport.
As part of DUNEX and the Hurricane Florence Supplemental Project the USGS is also conducting large-scale, long-term coastal change modeling with the aid of satellite-derived, historical shoreline observations. Satellite-derived shoreline positions (based on the CoastSat toolbox of Vos et al. 2019) are assimilated into the CoSMoS-COAST shoreline model (Vitousek et al. 2017, 2021) to produce a calibrated, site-specific hindcast of shoreline change in response to storms. The calibrated model is then run with future wave conditions to produce a forecast of coastal change from days to decades. The integrated modeling system demonstrates excellent agreement when compared with traditional survey data at Ocean Beach, California where the model is currently working. The DUNEX experiment will test the performance of the integrated modeling system on the U.S. east coast from Florida to Virginia.
Below are other science projects associated with DUNEX Modeling Waves, Water Levels, Sediment Transport, and Shoreline Change.
USGS DUNEX Operations on the Outer Banks
COAWST: A Coupled-Ocean-Atmosphere-Wave-Sediment Transport Modeling System
Large, collaborative field experiments such as DUNEX leverage observations of the coastal ocean made by multiple academic, agency, and NGO teams, providing the opportunity to grasp a broader picture of the forces responsible for coastal change. Despite deployment of many instruments, it’s impossible to measure everything, everywhere, at all times. Numerical models that represent the physical processes of the coastal ocean, such as waves, tides, currents, and sediment transport, allow us to fill in the observational dataset gaps in space or time. Numerical models can also be controlled to investigate specific physical processes to test hypotheses or compare to observations.
Numerical models are composed of a suite of mathematical equations that attempt to completely describe or estimate physical processes. For DUNEX, we will use a numerical model called COAWST to:
1) predict coastal ocean conditions during the experiment to support other scientists and
2) hindcast coastal ocean conditions and morphological changes during past storm events that were measured during the experiment.
Tools and Software
Numerical models that represent the physical processes of the coastal ocean, such as waves, tides, currents, and sediment transport, allow us to fill in the observational dataset gaps in space or time.
COAWST is the Coupled Ocean-Atmosphere-Wave-Sediment Transport modeling system, which links several models together to simulate forces such as waves and tidal currents and the interactions between them. COAWST has been developed at the USGS in collaboration with academic and other agency partners and has been used to study a wide range of interesting coastal ocean problems, such as rip currents, barrier island breaching, and estuarine circulation.
The forecast of coastal ocean conditions provided by COAWST give our USGS team and other DUNEX scientists information to assist with instrument deployments and surveying. It can also provide an initial dataset to compare against field observations or provide context.
After the experiment, we will hindcast particular storm events, or the quiescent periods in between storms, at very high spatial resolution (1-10 m) to investigate physical processes controlling coastal change. For example, wave breaking controls, in part, wave runup on the beach, surf zone circulation and mixing, and sediment transport in the nearshore. In collaboration with scientists collecting field data, we will evaluate and improve the model parameterizations that describe wave evolution in the nearshore. Additionally, we will explore the exchange of sand between the dune, beach, and nearshore, and the various conditions responsible for sand transport.
As part of DUNEX and the Hurricane Florence Supplemental Project the USGS is also conducting large-scale, long-term coastal change modeling with the aid of satellite-derived, historical shoreline observations. Satellite-derived shoreline positions (based on the CoastSat toolbox of Vos et al. 2019) are assimilated into the CoSMoS-COAST shoreline model (Vitousek et al. 2017, 2021) to produce a calibrated, site-specific hindcast of shoreline change in response to storms. The calibrated model is then run with future wave conditions to produce a forecast of coastal change from days to decades. The integrated modeling system demonstrates excellent agreement when compared with traditional survey data at Ocean Beach, California where the model is currently working. The DUNEX experiment will test the performance of the integrated modeling system on the U.S. east coast from Florida to Virginia.
Below are other science projects associated with DUNEX Modeling Waves, Water Levels, Sediment Transport, and Shoreline Change.