Terrain-following Ocean Modeling System (TOMS)

This web page describes an expert Terrain-following Ocean Modeling System (TOMS) for scientific and Navy operational applications. The design, development and testing of TOMS is sponsored by the Office of Naval Research (ONR), Ocean, Atmosphere, and Space Research Division. The TOMS lead developers are Arango (Rutgers University), Ezer (Princeton University), and Shchepetkin (UCLA). The steering executive committee includes Haidvogel (Rutgers University), McWilliams (UCLA), and Street (Stanford University). This ONR initiative is part of a larger effort to modernize the ocean forecasting capabilities of the Navy and includes other developers representing other modeling communities.


The long-term goal is to design, develop and test an expert Terrain-following Ocean Modeling System for scientific and operational applications over a wide range of scales from coastal to global. The primary focus is to implement the most robust set of options and algorithms for relocatable coastal forecasting systems. The system includes accurate and efficient numerical algorithms, a suite of vertical mixing schemes, interfaces for coupling with atmospheric forecasting models, multiple levels of nesting and composed grids, and tangent linear and adjoint algorithms for variational data assimilation (strong and weak constraint 4DVAR), ensemble forecasting and stability analysis. The parallel framework comprises both shared-memory (OpenMP) and distributed-memory (MPI) paradigms. The system also includes extensive web-based documentation and user-support software for model set-up, analysis and diagnostics.


Currently, ROMS and TOMS are identical. ROMS remains the scientific community model while TOMS becomes the operational community model. ROMS/TOMS is a split-explicit, free-surface, hydrostatic primitive equation ocean model with horizontal orthogonal curvilinear coordinates and stretched, terrain-following vertical coordinates.