John Warner, PhD
Science and Products
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...
COAWST System Components
The Coupled-Ocean-Atmospherre-Wave-Sediment Transport Modeling System (COAWST) modeling system currently contains the following sophisticated systems:
COAWST: A Coupled-Ocean-Atmosphere-Wave-Sediment Transport Modeling System
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...
Coastal System Change at Fire Island, New York
Fire Island is a 50-km long barrier island along the south shore of Long Island, New York. The island is comprised of seventeen year-round communities; federal, state, and county parks; and supports distinct ecosystems alongside areas of economic and cultural value. In addition to providing resources to its residents, the barrier island also protects the heavily-populated mainland from storm...
The Coupled Ocean-Atmosphere-Wave-Sediment Transport Modeling System
To responsibly manage our coastal resources requires an understanding of the processes responsible for coastal change. The CMHRP developed a Coupled Ocean–Atmosphere–Wave–Sediment Transport (COAWST) modeling system that allows the user to evaluate how different processes such as winds and waves,...
Open Ocean/Marine - Coastal System Change at Fire Island, New York
Geophysical mapping and research have demonstrated that the seabed on the inner continental shelf has a variety of shapes which are linked to long-term evolution of the barrier island. Regional-scale modeling forecasts how atmospheric forcing and oceanographic circulation case sand, gravel, and other materials to be transported by tides, winds, waves, fresh water fluxes, and density variations...
Estuarine Processes, Hazards, and Ecosystems
Estuarine processes, hazards, and ecosystems describes several interdisciplinary projects that aim to quantify and understand estuarine processes through observations and numerical modeling. Both the spatial and temporal scales of these mechanisms are important, and therefore require modern instrumentation and state-of-the-art hydrodynamic models. These projects are led from the U.S....
Cross-Shore and Inlets (CSI) Processes
Exchange of flows, sediment, and biological particles between the inner shelf and back-barrier estuaries are significant for determination of extreme water levels, maintenance and formation of inlets, barrier-island evolution, and pollutant and larval transport. These connections are controlled by cross-shore processes including wave-driven inner-shelf and near-shore processes, dune...
Coastal Model Applications and Field Measurements- Tools and Standards for Ocean Modeling
Ocean models provide critical information for coastal and marine spatial planning, emergency responders and for understanding implications of climate change and human activities. Models are run by numerous academic institutions and government agencies, typically with different access protocols that stifle use, comparison with data, and innovation.
Coastal Model Applications and Field Measurements
Numerical models are used by scientists, engineers, coastal managers, and the public to understand and predict processes in the coastal ocean. This project supports the development and application of open-source coastal models and has several objectives: 1) improve the code of numerical sediment-transport models by implementing new or improved algorithms; 2) obtain measurements of coastal...
Coastal Change Processes- South Carolina
Understanding the processes that control local sediment fluxes is critical in evaluating regional vulnerability to coastal erosion. This project task involves the analysis of observational data collected as part of the South Carolina Coastal Erosion Study (SCCES), and additional coastal process modeling for the Grand Strand region....
Coastal Change Processes- Cape Hatteras, NC
The most prominent morphologic features along the shoreline of the Carolinas are its four capes. From north to south, Cape Hatteras, Cape Lookout, Cape Fear, and Cape Romain segment the coastline into the northern outer banks, Raliegh Bay, Onslo Bay, and Long Bay regions. Continental shelf areas seaward of the capes are characterized by large, highly dynamic shoal complexes, which influence...
Numerical model of salinity transport and mixing in the Hudson River Estuary
Transport of material in an estuary is important for water quality and hazards concern. We studied these processes in the Hudson River Estuary, located along the northeast coast of the U.S. using the COAWST numerical modeling system. The model grid extends from the south at the Battery, NY to the north in Troy, NY.
Idealized COAWST model cases for studying the comparison of physical to numerical mixing with different tracer advection schemes in estuarine environments
The numerical simulation of estuarine dynamics requires accurate prediction for the transport of tracers such as temperature and salinity. All numerical models introduce two kinds of tracer mixing: 1) by parameterizing the tracer eddy diffusivity through turbulence models leading to a source of physical mixing and 2) discretization of the tracer advection term that leads to numerical mixing....
Evaluation 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...
Porchetta, Sara; Temel, O.; Warner, John C.; Muñoz-Esparza, J.C.; Monbaliu, J; van Beeck, J.; van Lipzig, N. Using tracer variance decay to quantify variability of salinity mixing in the Hudson River Estuary
The salinity structure in an estuary is controlled by time‐dependent mixing processes. However, the locations and temporal variability of where significant mixing occurs is not well‐understood. Here we utilize a tracer variance approach to demonstrate the spatial and temporal structure of salinity mixing in the Hudson River Estuary. We run a 4‐...
Warner, John C.; Geyer, W Rockwill; Ralston, David K.; Kalra, Tarandeep S. Wave-resolving Shoreline Boundary Conditions for Wave-Averaged Coastal Models
Downscaling broadscale ocean model information to resolve the fine-scale swash-zone dynamics has a number of applications, such as improved resolution of coastal flood hazard drivers, modeling of sediment transport and seabed morphological evolution. A new method is presented, which enables wave-averaged models for the nearshore circulation to...
Memmola, Francesco; Coluccelli, Alessandro; Russo, Aniello; Warner, John C.; Brocchini, Maurizio Meteotsunamis triggered by tropical cyclones
Tropical cyclones are one of the most destructive natural hazards and much of the damage and casualties they cause are flood-related. Accurate characterization and prediction of total water levels during extreme storms is necessary to minimize coastal impacts. While meteotsunamis are known to influence water levels and to produce severe...
Olabarrieta, Maitane; Shi, Luming; Nolan, David; Warner, John C. Investigating bedload transport under asymmetrical waves using a coupled ocean-wave model
Transport by asymmetrical wave motions plays a key role in cross-shore movement of sand, which is important for bar migration, exchange through tidal inlets, and beach recovery after storms. We have implemented a modified version of the SANTOSS formulation in the three-dimensional open-source Coupled-Ocean-Atmosphere-Wave-Sediment Transport (...
Kalra, Tarandeep S.; Sherwood, Christopher R.; Warner, John C.; Rafati, Yashar; Hsu, Tian Jian Wave-current interaction between Hurricane Matthew wave fields and the Gulf Stream
Hurricanes interact with the Gulf Stream in the South Atlantic Bight (SAB) through a wide variety of processes, which are crucial to understand for prediction of open-ocean and coastal hazards during storms. However, it remains unclear how waves are modified by large-scale ocean currents under storm conditions, when waves are aligned with the...
Hegermiller, Christie; Warner, John C.; Olabarrieta, Maitane; Sherwood, Christopher R. Relevance of wind stress and wave-dependent ocean surface roughness on the generation of winter meteotsunamis in Northern Gulf of Mexico
Meteotsunamis associated with passing squall lines are often observed ahead of cold fronts during winter seasons in Northern Gulf of Mexico. These types of meteotsunamis occur simultaneously with wind speed variations (~5-20 m/s) and sea-level atmospheric pressure oscillations (~1-6 hPa) with periods between 2 hours to several minutes. In order to...
Shi, Lijing; Olabarrieta, Maitane; Valle-Levinson, A; Warner, John C. Comparison of physical to numerical mixing with different tracer advection schemes in estuarine environments
The numerical simulation of estuarine dynamics requires accurate prediction for the transport of tracers such as temperature and salinity. During the simulation of these processes, all numerical models introduce two kinds of tracer mixing: 1) by parameterizing the tracer eddy diffusivity through turbulence models leading to a source of physical...
Kalra, Tarandeep S.; Li, Xiangyu; Warner, John C.; Geyer, W. R.; Wu, Hui Alongshore momentum balance over shoreface-connected ridges, Fire Island, NY
Hydrodynamic and hydrographic data collected on the inner shelf of Fire Island, NY, over a region of shoreface-connected ridges (SFCRs) are used to describe wind-driven circulation over uneven topographies along relatively straight coastlines. The data revealed a predominantly alongshore flow, under westward wind forcing, with localized offshore...
Ofsthun, Conor; Wu, Xiaodong; Voulgaris, George; Warner, John C. Persistent shoreline shape induced from offshore geologic framework: Effects of shoreface connected ridges
Mechanisms relating offshore geologic framework to shoreline evolution are determined through geologic investigations, oceanographic deployments, and numerical modeling. Analysis of shoreline positions from the past 50 years along Fire Island, New York, a 50 km long barrier island, demonstrates a persistent undulating shape along the western half...
Safak, Ilgar; List, Jeffrey H.; Warner, John C.; Schwab, William C. Change in morphology and modern sediment thickness on the inner continental shelf offshore of Fire Island, New York between 2011 and 2014: Analysis of hurricane impact
Seafloor mapping investigations conducted on the lower shoreface and inner continental shelf offshore of Fire Island, New York in 2011 and 2014, the period encompassing the impacts of Hurricanes Irene and Sandy, provide an unprecedented perspective regarding regional inner continental shelf sediment dynamics during large storm events. Analyses...
Schwab, William C.; Baldwin, Wayne E.; Warner, John C.; List, Jeffrey H.; Denny, Jane F.; Liste Munoz, Maria; Safak, Ilgar Rip currents and alongshore flows in single channels dredged in the surf zone
To investigate the dynamics of flows near nonuniform bathymetry, single channels (on average 30 m wide and 1.5 m deep) were dredged across the surf zone at five different times, and the subsequent evolution of currents and morphology was observed for a range of wave and tidal conditions. In addition, circulation was simulated with the numerical...
Moulton, Melissa; Elgar, Steve; Raubenheimer, Britt; Warner, John C.; Kumar, Nirnimesh
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.
Coupled-Ocean-Atmosphere-Waves-Sediment Transport (COAWST) Modeling System Training
Predicting Coastal Storm Impacts: 4th COAWST Model Training in the James Hunt Library at North Carolina State University, hosted by John Warner, Research Oceanographer of the USGS Woods Hole Coastal and Marine Science Center.
Predicting Coastal Storm Impacts: 4th COAWST Model Training
The USGS has been leading the development of a Coupled Ocean-Atmosphere-Waves-Sediment Transport (COAWST) Modeling System.
USGS Deploys Oceanographic Gear Offshore from Matanzas Inlet, St. Augustine, Florida
Matanzas is a natural, unstabilized inlet, which makes it an ideal location to study dynamic inlet processes in a non-maintained channel.
Advanced Model Training for Predicting Coastal Storm Impacts
The USGS has been leading the development of a Coupled Ocean-Atmosphere-Waves-Sediment Transport (COAWST) Modeling system.