Understanding the processes responsible for coastal change is important for managing both our natural and economic coastal resources. Storms are one of the primary driving forces causing coastal change from a coupling of wave- and wind-driven flows. To better understand storm impacts and their effects on our coastlines, there is an international need to better predict storm paths and intensities. To fill this gap, the USGS has been leading the development of a Coupled Ocean-Atmosphere-Waves-Sediment Transport (COAWST) Modeling System
COAWST is an open-source tool that combines many sophisticated systems that each provide relative earth-system components necessary to investigate the dynamics of coastal storm impacts. Specifically, the COAWST Modeling System includes an ocean component—Regional Ocean Modeling System (ROMS); atmosphere component—Weather Research and Forecast Model (WRF), hydrology component- WRF_Hydro; wave components—Simulating Waves Nearshore (SWAN), WAVEWATCHIII, and InWave; a sediment component—the USGS Community Sediment Models; and a sea ice model.
We began with a coupled modeling system as described in Warner et al (2008) and have enhanced that system to include concurrent one-way grid refinement in the ocean model, concurrent one-way grid refinement in the wave model, coupling an atmospheric model to include effects of sea surface temperature and waves, exchange of fields on refined grid levels, and interpolation mechanisms to allow the different models to compute on different grids. Full description provided in Warner et al (2010).
The USGS has provided and developed varying aspects of all these individual systems and provided enhanced capabilities to allow these components to feed back to one another. For example, a typical hurricane modeling simulation may include great details for the atmosphere component, but with limited connectivity to the ocean. However, with the COAWST system, these simulations will allow the ocean and waves to dynamically evolve and provide a feedback to the atmosphere simulation. This will modify the storm development and provide a more realistic suite of physical storm processes.
COAWST related resources
COAWST Training Workshops
COAWST System Components
COAWST Data and Tools Products
Idealized COAWST numerical model for testing marsh wave thrust and lateral retreat dynamics routines
COAWST model of Barnegat Bay creeks to demonstrate marsh dynamics
Idealized numerical model for Submerged Aquatic Vegetation (SAV) growth dynamics
Numerical model of Submerged Aquatic Vegetation (SAV) growth dynamics in West Falmouth Harbor
USGS Barnegat Bay Hydrodynamic Model for March-September 2012
Below are publications associated with this project.
Development of a three-dimensional, regional, coupled wave, current, and sediment-transport model
Modeling the dynamics of salt marsh development in coastal land reclamation
Evaluation of a roughness length parametrization accounting for wind–wave alignment in a coupled atmosphere–wave model
Evaluation of a roughness length parametrization accounting for wind–wave alignment in a coupled atmosphere–wave model
Development of a submerged aquatic vegetation growth model in the Coupled Ocean–Atmosphere–Wave–Sediment Transport (COAWST v3.4) model
Hydrodynamic and morphologic response of a back-barrier estuary to an extratropical storm
Spatial distribution of water level impact to back-barrier bays
Hydrodynamics and sediment mobility processes over a degraded senile coral reef
Physical response of a back-barrier estuary to a post-tropical cyclone
Development of a coupled wave-flow-vegetation interaction model
Formation of fine sediment deposit from a flash flood river in the Mediterranean Sea
Investigation of hurricane Ivan using the coupled ocean-atmosphere-wave-sediment transport (COAWST) model
Implementation of the vortex force formalism in the coupled ocean-atmosphere-wave-sediment transport (COAWST) modeling system for inner shelf and surf zone applications
COAWST Modeling System v3.4
Coupled-Ocean-Atmosphere-Wave-Sediment Transport (COAWST) Modeling System
The Coupled-Ocean-Atmosphere-Wave-Sediment Transport (COAWST) Modeling System is an agglomeration of open-source modeling components that has been tailored to investigate coupled processes of the atmosphere, ocean, and waves in the coastal ocean.
- Overview
Understanding the processes responsible for coastal change is important for managing both our natural and economic coastal resources. Storms are one of the primary driving forces causing coastal change from a coupling of wave- and wind-driven flows. To better understand storm impacts and their effects on our coastlines, there is an international need to better predict storm paths and intensities. To fill this gap, the USGS has been leading the development of a Coupled Ocean-Atmosphere-Waves-Sediment Transport (COAWST) Modeling System
The COAWST modeling system joins an ocean model, an atmosphere model, a wave model, and a sediment transport model for studies of coastal change. COAWST is an open-source tool that combines many sophisticated systems that each provide relative earth-system components necessary to investigate the dynamics of coastal storm impacts. Specifically, the COAWST Modeling System includes an ocean component—Regional Ocean Modeling System (ROMS); atmosphere component—Weather Research and Forecast Model (WRF), hydrology component- WRF_Hydro; wave components—Simulating Waves Nearshore (SWAN), WAVEWATCHIII, and InWave; a sediment component—the USGS Community Sediment Models; and a sea ice model.
We began with a coupled modeling system as described in Warner et al (2008) and have enhanced that system to include concurrent one-way grid refinement in the ocean model, concurrent one-way grid refinement in the wave model, coupling an atmospheric model to include effects of sea surface temperature and waves, exchange of fields on refined grid levels, and interpolation mechanisms to allow the different models to compute on different grids. Full description provided in Warner et al (2010).
The USGS has provided and developed varying aspects of all these individual systems and provided enhanced capabilities to allow these components to feed back to one another. For example, a typical hurricane modeling simulation may include great details for the atmosphere component, but with limited connectivity to the ocean. However, with the COAWST system, these simulations will allow the ocean and waves to dynamically evolve and provide a feedback to the atmosphere simulation. This will modify the storm development and provide a more realistic suite of physical storm processes.
- Science
COAWST related resources
COAWST Training Workshops
Currently the Coupled-Ocean-Atmospherre-Wave-Sediment Transport Modeling System (COAWST) has 800 registered users from around the world. To advance the user community of the COAWST modeling system, the USGS has held trainings every two years since 2012. In general, the trainings provide both a hands-on tutorial of the system and fundamental information about the modeling components. Users from...COAWST System Components
The Coupled-Ocean-Atmospherre-Wave-Sediment Transport Modeling System (COAWST) modeling system currently contains the following sophisticated systems: - Data
COAWST Data and Tools Products
Idealized COAWST numerical model for testing marsh wave thrust and lateral retreat dynamics routines
There are two idealized domains developed in this work to test the marsh dynamics in the COAWST modeling framework. 1. First idealized domain is to test and verify the lateral thrust calculations. 2. Second idealized domain is to test the implementation of lateral retreat formulations.COAWST model of Barnegat Bay creeks to demonstrate marsh dynamics
The COAWST (Coupled Ocean-Atmosphere-Wave-Sediment Transport) modeling framework was extended to add two key processes that affect marshes, erosion due to lateral wave thrust (LWT) and vertical accretion due to biomass productivity. The testing of the combined effects of integrating these two processes was done by modeling marsh complexes within Forsythe National Wildlife Refuge and the Barnegat BIdealized numerical model for Submerged Aquatic Vegetation (SAV) growth dynamics
An idealized domain is setup to test the development of Submerged Aquatic Vegetation (SAV) growth model within the Coupled Ocean-Atmosphere-Wave-Sediment Transport (COAWST) model. The change in SAV biomass is computed from temperature, nutrient loading and light predictions obtained from coupled hydrodynamics (temperature), bio-geochemistry (nutrients) and bio-optical (light) models. In exchange,Numerical model of Submerged Aquatic Vegetation (SAV) growth dynamics in West Falmouth Harbor
The development of Submerged Aquatic Vegetation (SAV) growth model within the Coupled Ocean-Atmosphere-Wave-Sediment Transport (COAWST) model leads to a change in SAV biomass. The SAV biomass is computed from temperature, nutrient loading and light predictions obtained from coupled hydrodynamics (temperature), bio-geochemistry (nutrients) and bio-optical (light) models. In exchange, the growth ofUSGS Barnegat Bay Hydrodynamic Model for March-September 2012
Simulation of hydrodynamic circulation in Barnegat Bay for the period from 03-01-2012 to 10-01-2012. The bathymetry of the model was based on the National Ocean Service Hydrographic Survey data, and updated with recent bathymetric measurements. At the landward end (western boundary), we specified point sources of freshwater in accordance with USGS streamflow measurements at 7 gauges, and a radiati - Publications
Below are publications associated with this project.
Development of a three-dimensional, regional, coupled wave, current, and sediment-transport model
We are developing a three-dimensional numerical model that implements algorithms for sediment transport and evolution of bottom morphology in the coastal-circulation model Regional Ocean Modeling System (ROMS v3.0), and provides a two-way link between ROMS and the wave model Simulating Waves in the Nearshore (SWAN) via the Model-Coupling Toolkit. The coupled model is applicable for fluvial, estuarFilter Total Items: 14Modeling the dynamics of salt marsh development in coastal land reclamation
The valuable ecosystem services of salt marshes are spurring marsh restoration projects around the world. However, it is difficult to determine the final vegetated area based on physical drivers. Herein, we use a 3D fully coupled vegetation-hydrodynamic-morphological modeling system (COAWST), to simulate the final vegetation cover and the timescale to reach it under various forcing conditions. MarEvaluation of a roughness length parametrization accounting for wind–wave alignment in a coupled atmosphere–wave model
The importance of wind energy as an alternative energy source has increased over the latest years with more focus on offshore winds. A good estimation of the offshore winds is thus of major importance for this industry. Up to now the effect of the wind–wave (mis)alignment has not yet been taken into account in coupled atmosphere–wave models to study the vertical wind profile and power production eEvaluation of a roughness length parametrization accounting for wind–wave alignment in a coupled atmosphere–wave model
The importance of wind energy as an alternative energy source has increased over the latest years with more focus on offshore winds. A good estimation of the offshore winds is thus of major importance for this industry. Up to now the effect of the wind–wave (mis)alignment has not yet been taken into account in coupled atmosphere–wave models to study the vertical wind profile and power production eDevelopment of a submerged aquatic vegetation growth model in the Coupled Ocean–Atmosphere–Wave–Sediment Transport (COAWST v3.4) model
The coupled biophysical interactions between submerged aquatic vegetation (SAV), hydrodynamics (currents and waves), sediment dynamics, and nutrient cycling have long been of interest in estuarine environments. Recent observational studies have addressed feedbacks between SAV meadows and their role in modifying current velocity, sedimentation, and nutrient cycling. To represent these dynamic proceHydrodynamic and morphologic response of a back-barrier estuary to an extratropical storm
We investigated the hydrodynamic and morphologic response of Barnegat Bay-Little Egg Harbor, New Jersey, USA to Hurricane Sandy. We implemented a three-dimensional, coupled ocean-wave-sediment transport model of the estuary and explored the role of offshore water levels, offshore waves, local winds and waves by systematically removing forcings from a series of simulations. Offshore water levels haSpatial distribution of water level impact to back-barrier bays
Water level in semi-enclosed bays, landward of barrier islands, is mainly driven by offshore sea level fluctuations that are modulated by bay geometry and bathymetry, causing spatial variability in the ensuing response (transfer). Local wind setup can have a secondary role that depends on wind speed, fetch, and relative orientation of the wind direction and the bay. Inlet geometry and bathymetry pHydrodynamics and sediment mobility processes over a degraded senile coral reef
Coral reefs can influence hydrodynamics and morphodynamics by dissipating and refracting incident wave energy, modifying circulation patterns, and altering sediment transport pathways. In this study, the sediment and hydrodynamic response of a senile (dead) barrier reef (Crocker Reef, located in the upper portion of the Florida Reef Tract) to storms and quiescent conditions was evaluated using fiePhysical response of a back-barrier estuary to a post-tropical cyclone
This paper presents a modeling investigation of the hydrodynamic and sediment transport response of Chincoteague Bay (VA/MD, USA) to Hurricane Sandy using the Coupled Ocean-Atmosphere-Wave-Sediment-Transport (COAWST) modeling system. Several simulation scenarios with different combinations of remote and local forces were conducted to identify the dominant physical processes. While 80% of the waterDevelopment of a coupled wave-flow-vegetation interaction model
Emergent and submerged vegetation can significantly affect coastal hydrodynamics. However, most deterministic numerical models do not take into account their influence on currents, waves, and turbulence. In this paper, we describe the implementation of a wave-flow-vegetation module into a Coupled-Ocean-Atmosphere-Wave-Sediment Transport (COAWST) modeling system that includes a flow model (ROMS) anFormation of fine sediment deposit from a flash flood river in the Mediterranean Sea
We identify the mechanisms controlling fine deposits on the inner-shelf in front of the Besòs River, in the northwestern Mediterranean Sea. This river is characterized by a flash flood regime discharging large amounts of water (more than 20 times the mean water discharge) and sediment in very short periods lasting from hours to few days. Numerical model output was compared with bottom sediment obsInvestigation of hurricane Ivan using the coupled ocean-atmosphere-wave-sediment transport (COAWST) model
The coupled ocean–atmosphere–wave–sediment transport (COAWST) model is used to hindcast Hurricane Ivan (2004), an extremely intense tropical cyclone (TC) translating through the Gulf of Mexico. Sensitivity experiments with increasing complexity in ocean–atmosphere–wave coupled exchange processes are performed to assess the impacts of coupling on the predictions of the atmosphere, ocean, and wave eImplementation of the vortex force formalism in the coupled ocean-atmosphere-wave-sediment transport (COAWST) modeling system for inner shelf and surf zone applications
The coupled ocean-atmosphere-wave-sediment transport modeling system (COAWST) enables simulations that integrate oceanic, atmospheric, wave and morphological processes in the coastal ocean. Within the modeling system, the three-dimensional ocean circulation module (ROMS) is coupled with the wave generation and propagation model (SWAN) to allow full integration of the effect of waves on circulation - Software
COAWST Modeling System v3.4
Coupled ocean atmosphere wave sediment transport modeling systemCoupled-Ocean-Atmosphere-Wave-Sediment Transport (COAWST) Modeling System
The Coupled-Ocean-Atmosphere-Wave-Sediment Transport (COAWST) Modeling System is an agglomeration of open-source modeling components that has been tailored to investigate coupled processes of the atmosphere, ocean, and waves in the coastal ocean.