2006 Ocean Sciences Meeting SEACOOS Poster - An Initial Assessment of East Florida Shelf Information System (EFSIS) Driven by Global NCOM Products

For the program on "Ocean Prediction VI: Posters," OS26N-15. EFSIS is a nowcast/forecast system for the Straits of Florida and East Florida Shelf, one of three sub-regions of Southeast Atlantic Coastal Ocean Observing System (SEACOOS) modeling efforts, and it is based on Princeton Ocean Model (POM) configured in a curvilinear coordinate system with 2~10 km resolution and 25 sigma levels. EFSIS has been running since October 2004 with open boundary forcing from the Global Navy Coastal Ocean Model (NCOM), which provides 3-hour interval velocity and temperature/salinity analysis and forecast data up to 72 hours on a daily basis. At the sea surface, the North America Model (NAM), formerly ETA, from NCEP provides wind and atmospheric pressure forcing, and EFSIS temperature/salinity are relaxed to either monthly climatology or Global NCOM fields with a 1-day restoring time scale. NAM forecasts up to 84 hours at 00Z. A tidal model, which has eight tidal constituents and encompasses the EFSIS model domain, provides tidal forcing, and a modified Flather boundary condition is used to combine Global NCOM forcing with tidal forcing. For validation, EFSIS products have been compared with several different types of observational data such as coastal sea level, surface water temperature, volume transport estimate at 27o N, surface currents, velocity profiles, and velocity transects. All these comparisons are encouraging; for example, correlations of low-pass filtered coastal sea levels between EFSIS and observations are high, EFSIS reproduces well small mesoscale eddies observed by HF radar (also, the spatial patterns of means and standard deviations are highly correlated), and the spatial distributions of EFSIS velocity at 25.5oN agree well with those observed by a towed ADCP. But, there are also discrepancies between EFSIS and observations that improvement can be expected with increasing resolution, better choice of model parameters (for example, HORCON and inverse Prandtl number), better topography, etc. A major point of this investigation is to determine how well EFSIS can perform with careful attention to forcing, bottom topography, model configuration, etc. Conversely, the aim is to identify what problems may exist that need the assistance of data assimilation for their remediation. I Bang, *C N Mooers