Towards operational modeling in the South Atlantic Bight

The implementation of a nowcast/forecast operational model system is described for the middle portion of the South Atlantic Bight of the United States coast. There are three components. First, a digital monthly climatology for temperature and salinity is objectively derived for the continental shelf of the South Atlantic Bight. The diagnostic responses to the resulting mass fields and to the monthly climatological wind fields derived from the Comprehensive Ocean-Atmosphere Data Set are computed. This climatology will provide initial mass fields for prognostic studies as well as initial conditions for the operational model system. Second, an extensive tidal analysis of historical and recent observations is combined with high resolution numerical model solutions to provide a new perspective on barotropic tidal dynamics in the South Atlantic Bight. It is shown that substantial reduction in error is achieved between observations and a model solution that includes a first-order representation of the complex coastline along the Georgia and South Carolina coast. This solution is compared to a model solution that does not resolve this region. Third, the operational system is described. It is composed of a sequence of shallow-water finite element models that compute prior estimates of the shelf circulation and water level. A data-assimilative component is used to reduce the discrepancy between the forward models and observations to improve the prior estimate. Initial results on barotropic skill in the tidal, weather, and very low frequency bands are discussed.