Detecting Internal Wave Activity in Ocean Models

Internal waves can create large changes in the ocean’s vertical density structure. These changes affect the sound speed and buoyancy within the water column on scales that can impact naval operations. The operational Navy Coastal Ocean Model (NCOM) run by the Naval Oceanographic Office has the ability to forecast internal tidal waves when setup at sufficient grid resolutions. A technique for extracting the location of these internal tidal wave beds from NCOM fields will be discussed. The method involves identifying an “active isotherm” utilizing the National Oceanic and Atmospheric Administration’s Ferret software, which is an interactive computer visualization and analysis environment. The technique is demonstrated in specific areas of the Western Pacific water.