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This report describes the development of the Eastcoast 2001 database of computed tidal elevation and velocity constituents within the Western North Atlantic Tidal (WNAT) domain. The WNAT domain encompasses the Western North Atlantic Ocean, Gulf of Mexico, and Caribbean Sea. The computations are based on a strategically designed finite element grid and the coastal hydrodynamic circulation model, ADCIRC. The resulting Eastcoast 2001 database defines the computed elevation and velocity amplitude and phase for the O1, K1, Q1, M2, S2, N2, and K2 tidal constituents. The Eastcoast 2001 database is significantly more accurate than the previous Eastcoast 1995 and Eastcoast 1991 databases based on the following feature improvements: (a) a new grid generation technique with better node placement and distribution, (b) a significantly greater number of total nodes, (c) a more accurate coastal boundary, and (d) inclusion of more reliable bathymetric databases. The new grid generation technique is the combination of two a priori mesh criteria: (a) The wavelength to grid size ratio and (b) the topographic length scale criteria. This combination optimally and more accurately places grid nodes in areas where high resolution is needed. Error analysis of computed versus measured elevation amplitude and phase at 101 stations in addition to an assessment of measured data errors globally and locally quantifies The level of reliability of the computed constituents., Original contains color plates: All DTIC reproductions will be in black and white.

This Coastal and Hydraulic Engineering Technical Note (CHETN) describes the methodology and input requirements for the leaky-barrier boundary feature in the Advanced Circulation (ADCIRC) coastal hydrodynamics code versions 40.02 and higher. This feature calculates flow over and through structures such as levees and jetties., The original document contains color images.

Formulation of a numerical storm surge model directly affects the physical content of the predicted storm surge response. The influence of domain size and grid structure on computations of storm surge generation in the coastal region are studied. Storm surge response along the Florida shelf in the Gulf of Mexico due to Hurricane Kate is examined over three domains using two different open ocean boundary forcing functions. The computed storm surge response indicates that a small domain situated primarily on the continental shelf is inadequate since cross shelf boundaries are in regions of significant storm surge generation where surge and therefore boundary conditions are not known a priori. A second domain including the entire Gulf of Mexico basin captures the primary storm surge well but may not correctly model resonant modes. The dependence of these modes on interactions with contiguous basins makes accurate setup by the boundary condition specification difficult. The primary storm surge response as well as resonant modes excited by the storm are best represented using the largest domain, which encompasses the western North Atlantic ocean, the Caribbean Sea, and the Gulf of Mexico. This domain with deep Atlantic ocean boundaries facilitates simple boundary condition specification and minimizes the influence of boundary conditions on storm surge generation in the coastal region. Basin resonant modes and basin interactions are also captured.

This report describes the application of ADCIRC-2DDI, a two-dimensional depth-averaged barotropic hydrodynamic model, to the eastern North Pacific in order to develop a tidal constituent database. Issues that are emphasized in the development of the Eastern North Pacific Tidal (ENPACT) model include the specification of a geometrically and hydrodynamically simple open boundary, the use of large domains, and the advantages of using a graded finite element grid to selectively resolve flow features of interest. The ENPACT model is coupled to a finite element global ocean model at the open boundary and forced with five diurnal and semidiurnal astronomical tidal constituents (K1, O1, M2, S2, and N2). Tidal potential forcing is applied to the interior of the domain for the same constituents. The structures of the various tides are examined and the results of the tidal simulations are compared with field data at 72 fixed tidal elevation stations. (AN)

This report describes the application of model ADCIRC-2DDI, a two- dimensional, depth-integrated, finite-element-based hydrodynamic circulation code, to the western North Atlantic, Gulf of Mexico and Caribbean Sea in order to develop a tidal constituent database. Issues that are emphasized in the development of the Western North Atlantic Tidal (WNAT) model include the definition of hydrodynamically simple open ocean boundaries; the use of large domains; the importance of a high degree of grid resolution in coastal regions; and the use of finite element meshes with highly varying nodal densities in order to minimize the size of the discrete problem. The development of an optimal graded finite element mesh is based on regular and graded grid convergence studies using an M2 tidal forcing function on the boundary and within the domain. The optimal graded mesh is then forced for eight diurnal and semidiurnal astronomical tidal constituents (K1, O1, PI, Ql, M2, S2, N2, and K2) on the open ocean boundary by coupling to Schwiderski's (1979; 1981 a-g) global model results as well as within the interior domain using a tidal potential forcing function. The structure of the various tides is examined and results are compared to field data at 77 stations.... Bottom stress, Finite element method, Three-dimensional model, Circulation model, Hydrodynamic model, Two-dimensional model, Direct stress solution, Numerical model., See also Report 1, AD-A261 608. Prepared in collaboration with Dept. of Civil Engineering and Geological Science, University of Notre Dame, Notre Dame, IN and University of North Carolina at Chapel Hill, Institute of Marine Sciences, Morehead City, NC.

This report describes the theory, methodology, and verification of the ADCIRC (ADvanced CIRCulation) finite element numerical models. ADCIRC-2DDI is a two-dimensional, depth-integrated hydrodynamic model. ADCIRC-3DL is a three-dimensional model that couples the external mode solution generated by ADCIRC2DDI to a locally one-dimensional internal mode solution. The numerical internal mode solution can be obtained using either velocity or stress as the dependent variable. ADCIRC has been developed to simulate hydrodynamic circulation along shelves, coasts, and within estuaries. To allow long numerical simulations (on the order of a year) over very large computational domains (for example, the entire east coast of the United States), ADCIRC has been designed to have high computational efficiency and has been tested extensively for both hydrodynamic accuracy and numerical stability. The results of these tests are included in this report., Prepared in collaboration with University of North Carolina at Chapel Hill, Institute of Marine Sciences, Morehead City, NC and University of Notre Dame, Department of Civil Engineering, Notre Dame, IN.