The 1/12 deg Global HYCOM Nowcast/Forecast System

Abstract : Development of an advanced global ocean nowcasting/forecasting system has been of long-time US Navy interest. Such a system will provide the capability to depict (nowcast) and predict (forecast) the oceanic "weather", some components of which include the three dimensional (3-D) ocean temperature, salinity and current structure, the surface mixed layer and the location of mesoscale features such as eddies, meandering currents and fronts. The space scales of these eddies and meandering currents are typically about 100 km and currents speeds can easily exceed 1 mis in the western boundary current regions of the Kuroshio, Gulf Stream and Somali Current. So, relatively high horizontal and vertical resolution numerical ocean models are needed to depict the 3-D ocean structure with accuracy superior to climatology and/or persistence (i.e. a forecast of no change). Knowledge of the oceanic mesoscale has many naval applications, including tactical planning, optimum track ship routing, search and rescue operations, long-range weather prediction, inputs to coastal models, and knowledge of high current shear zones.