The Navy Layered Ocean Model Users Guide

Abstract : This report is a users guide to the Navy's hydrodynamic (isopycnal) nonlinear, primitive equation, layered ocean circulation model. The model retains the free surface and uses a semi-implicit time scheme that treats all gravity waves implicitly. It can handle full-scale bottom topography, provided it is confined to the lowest layer, and an arbitrary coastline geometry. The model has been in use at the Naval Oceanographic and Atmospheric Research Laboratory for more than 10 years for simulations of the ocean circulation in the Gulf of Mexico, the Caribbean Sea, the Alboran Sea, the western Mediterranean Sea, and the global oceans. In conjunction with the issuance of this report, the model code is being made available to the ocean modeling community. The vertically integrated equations of motion and their finite difference discretization on a C-grid is presented, as is a description on the semi-implicit time scheme, the boundary conditions, and the external forcing. The model code contains internal documentation that fully describes the user- specified model parameters and data sets. This report also contains general information about how to use the model, in particular, how to set it up for a new ocean region and how to port it to a new computer system. thermodynamic ocean model, world ocean, numerical model, Gulf of Mexico, ocean circulation model, energetics