Coastal Storm Modeling System

Event Simulations for Accurate Risk Assessment

Most existing coastal storm modeling systems focus on developing effective empirical tuning methods for optimizing calibration. This works well for operational systems but does not address the critical needs for advancing modeling technology. A robust, standardized approach to more accurately establishing the risk of coastal communities to future occurrences of storm events is required.

Assesses Impact of Storm Events on Coastal Communities

Through focused research and a spiral development strategy, engineers at the ERDC Coastal and Hydraulics Laboratory (CHL) have produced the Coastal Storm Modeling System (CSTORM-MS)—a comprehensive system of highly skilled and highly resolved models used to simulate coastal storms and accurately assess risk to coastal communities. With physics-based modeling capabilities, CSTORM-MS integrates a suite of high fidelity storm modeling tools to support a wide range of coastal engineering needs for simulating the following:

• Tropical and extra-tropical storms
• Wind, wave, and water levels
• Coastal response, including erosion, breaching and accretion

CSTORM-MS more rigorously represents the underlying physical processes than existing coastal storm modeling systems. It does not have to adjust or tune coefficients to produce realistic results, reducing dependency on empirical tuning factors. Through its powerful and user-friendly interface, CSTORM-MS configures models that are more generally applicable and required for accurate risk assessment of coastal storm than existing systems.

Adapts to New Technology for Increased Modeling Power

CHL engineers designed CSTORM-MS to be both expandable and upgradable. With the aid of new graphical user interfaces (GUI) in the Surface-water Modeling System (SMS), CSTORM-MS provides the following:

• New work flow with tightly-coupled models capable of using the Earth System Modeling Framework (ESMF)
• Timely feedback responses into each model for improved physical responses
• Reduction in overall execution costs as tightly coupled responses between models do not require a re-run
• Reduction in user input for configuring model interactions

In addition to improved physical responses, using ESMF standards allows for an almost “plug-n-play” capability for models. This allows different models to be applied within the present system, and the system can be expanded to include new capabilities, such as environmental models, for future applications.

The new GUI work flow system and tightly coupled models represent an enabling technology for more comprehensive studies on flood and shore protection and sediment management, helping to reduce human errors that happen when executing multi-step modeling processes.

By making use of the ESMF standards and ensuring the individual models and the CSTORM coupler itself are ESMF compliant means that the system can be readily used for multiple agency modeling needs. The spiral development approach allows for end users to continually have access to a robust set of tools even while future components are being developed and incorporated into the system.

Success Stories

CSTORM-MS technologies have been successfully applied to many projects over the last few years, including storm modeling and flood mapping support for the following:

• Hur­ricane Katrina Interagency Performance Evaluation Task Force
• Louisi­ana Coastal Protection and Restoration  Program
• Mississippi Coastal Improvement Program
• North Carolina Floodplain Mapping Program
• Federal Emergency Man­agement Agency
• Nuclear Regulatory Commission

Features

To provide realistic coastal storm simulations, CSTORM-MS requires the integration of the following complex numerical models:

Atmospheric Forcing

• Provides the dominant driving force for coastal storm simulations
• Improvements to wind and pressure field estimations for tropical storms within the planetary boundary layer (PBL) model
• Easy access to hurricane/tropical storm databases  for creating synthetic storms and visualizing PBL

Waves

• Includes a deepwater wave model (WAM) and nearshore wave model (STWAVE)
• Improved representation of bottom friction and diffraction in STWAVE and improved STWAVE nu­merics
• SMS GUIs added for WAM and STWAVE and allow easy set-up, running and result analysis for both models

Nearshore Dynamics

• New physics-based tools are in development to predict profile and shoreline change, including the Coastal 2D (horizontal) steady-state nearSHORE morphology response model (CSHORE)

Circulation and Storm Surge

• Further developing the Advanced Circulation (ADCIRC) model to simulate the effects storm surge and circulation have on inundation, flooding, sediment transport and beach erosion

Test and Evaluation

• Links model output with histori­cal data through robust statistical tools
• Provides in-depth error analysis and performance assessment of model results to facilitate continued model improvements

System Integration

• User-friendly integrated system of fully coupled coastal process modeling tools
• Flexible and expandable computational coupler for application on desktop or high-performance computing resources
• Computational coupler employs a two-way scheme that enhances represented physics and improves computational time

See the CSTORM-MS Features Web page for full details.

Status

The focus of spiral three will concentrate on waves with the development of a new time-stepping unstructured wave model (TSWAVE). The new model represents an effort for advancement of both deepwater and nearshore wave modeling technology to include consistently scaled, spectral source terms and the ability to accurately conform to complicated coastlines and coastal structures. This new unstructured wave model will still have the ability to run on a different mesh than the hydrodynamic mesh in order to allow for proper and optimal resolution of each model without having to over resolve one for the other.

For more information about CSTORM-MS, please visit CHL or read ASCE 2011 Solutions to Coastal Disasters Conference paper (log-in required).

Questions about CSTORM-MS?
ERDC Points of Contact
Contact: Chris Massey
Email: Chris.Massey@usace.army.mil
Phone: 601-634-2406