User:Cfulcher unc/sandbox

ADCIRC is a high-performance, cross-platform, computational hydrodynamic modeling system used to solve time-dependent, free surface circulation and transport problems in two and three dimensions. It was originally developed by Richard A. Luettich, Jr. of the University of North Carolina at Chapel Hill and Joannes J. Westerink of the University of Notre Dame as a tool to solve the shallow water equations using a continuous Galerkin finite element method on an unstructured mesh. Subsequently, it has become a widely-adopted model with an extensive user and developer-base within the global coastal and ocean modeling community. The ADCIRC system includes an independent multi-algorithmic wind forecast model and also has advanced coupling capabilities, allowing it to integrate effects from sediment transport, ice, waves, surface runoff, and baroclinicity.

It has been used extensively in the prediction of coastal flooding due to hurricanes. The U.S. Coast Guard has also used ADCIRC model results, as prepared by the Advanced Surge Guidance System (ASGS), during Hurricanes Irene, Isaac, and Sandy to aid storm-related decisions, such as deployment locations and maintaining continuity of operations.

History
The two principal developers of the ADCIRC coastal circulation and storm surge model are Dr. Rick Luettich at the University of North Carolina at Chapel Hill and Joannes Westerink at the University of Notre Dame.

Currently ADCIRC is maintained with a private repository. In addition to the the two principal developers, there are also additional developers who work to improve the code and add new functionality. The key developers are:
 * Brian Blanton (RENCI)
 * Clint Dawson (University of Texas at Austin)
 * Casey Dietrich (N.C. State University)
 * Jason Fleming (Seahorse Coastal Consulting)
 * Randall Kolar (University of Oklahoma at Norman)
 * Chris Massey (ERDC Coastal and Hydraulics Laboratory)

Results
ADCIRC models couple rain and wind forecasts with hydrologic, storm surge, and wave models to provide detailed and accurate predictions of coastal flooding.

Modeling results can be viewed at the Coastal Emergency Risks Assessment website.

Computational Specifics
ADCIRC equations have been formulated using the traditional hydrostatic pressure and Boussinesq approximations and have been discretized in space using the finite element (FE) method and in time using the finite difference (FD) method.

ADCIRC can be run either as a two-dimensional depth integrated (2DDI) model or as a three-dimensional (3D) model. In either case, elevation is obtained from the solution of the depth-integrated continuity equation in Generalized Wave-Continuity Equation (GWCE) form. Velocity is obtained from the solution of either the 2DDI or 3D momentum equations. All nonlinear terms have been retained in these equations.

ADCIRC can be run using either a Cartesian or a spherical coordinate system.

The GWCE can be solved using either a consistent or a lumped mass matrix (via a compiler flag) and an implicit or explicit time stepping scheme (via variable time weighting coefficients). If a lumped, fully explicit formulation is specified, no matrix solver is necessary. In all other cases the GWCE is solved using the Jacobi preconditioned iterative solver from the ITPACKV 2D package.

The 2DDI momentum equations are lumped and therefore require no matrix solver. In 3D, vertical diffusion is treated implicitly and the vertical mass matrix is not lumped, thereby requiring the solution of a complex, tri-diagonal matrix problem over the vertical at every horizontal node.

ADCIRC boundary conditions include:
 * specified elevation (harmonic tidal constituents or time series)
 * specified normal flow (harmonic tidal constituents or time series)
 * zero normal flow
 * slip or no slip conditions for velocity
 * external barrier overflow out of the domain
 * internal barrier overflow between sections of the domain
 * surface stress (wind and/or wave radiation stress)
 * atmospheric pressure
 * outward radiation of waves (Sommerfield condition)

Potential Applications
ADCIRC high performance computational models of coastal ocean hydrodynamics and transport can be applied to a variety of real engineering problems.

ADCIRC models compute water surface elevations, currents and transport of heat, salinity, pollutants and sediment within ocean basins, the continental shelf, estuaries, inlets, channels and adjacent floodplains.

These computational models evaluate and design for :
 * Coastal flooding due to hurricanes
 * Currents for shipping operations, dredging, and harbor design
 * Shoreline erosion/accretion and coastal morphology
 * Sewage and waste heat disposal
 * Water resources management – fisheries management

Applications to Date
ADCIRC computer models have helped the U.S. Coast Guard, FEMA and local emergency management services along the U.S. East Coast respond to hurricanes in 2010, 2011, and 2012.

ADCIRC models are being applied to redesign the Hurricane Protection System in Southern Louisiana as well as to establish flood elevation levels for the FEMA Digital Flood Insurance Rate Maps (DFIRMS).

ADCIRC is being used by The Office of Coast Survey (NOAA) as part of HSOFS to predict storm surge and help the National Hurricane Center produce a more "accurate flooding assessment for response and recovery."

ADCIRC is being used by ESTOFS (Extratropical Surge and Tide Operational Forecast System) by NOAA to provide "a second operational set of forecast guidance in addition to ET-SURGE (ETSS) model".

A boot camp is offered annually to train new users in ADCIRC, typically in late April/early May. Check the the "News" tab at the top of the ADCIRC homepage in late January for the annual announcement.

A User's Meeting is also held annually for user's to gather and share their work with ADCIRC. Information from previous year's meetings can be accessed through the "News" tab at the top of the ADCIRC homepage. Check this tab for announcements of future meetings (usually announced in January of each year and held at the end of April/beginning of May).

Honors
The ADCIRC model team has won numerous awards, including the International Data Corporation (IDC)’s HPC Innovation Excellence Award in June, 2013. The HPC Award recognizes noteworthy achievements by users of high performance computing (HPC) technologies that advance science and generate a significant return on investment (ROI). Additionally, the ADCIRC team twice received the U.S. Department of Homeland Security Science and Technology Impact Award in 2010 and 2012. These awards were given in recognition of the ADCIRC team’s contribution to safeguarding lives and property through prediction of coastal flooding.