The circulation, and ecosystems, of the coastal ocean are under the strong influence of the coastline morphology and the continental margin bottom topography and their various anomalies. They are also under the strong influence of atmospheric forcing, tidal forcing, boundary current forcing, and runoff from rivers, etc. These influences vary strongly from coastal region-to-coastal region; hence, one COOS design may not fit all.
As a specific example, the Straits of Florida - Florida Current - East Florida Shelf complex is considered. Predictions with the East Florida Shelf Information System (EFSIS, an implementation of the Princeton Ocean Model (POM)) a nowcast/forecast system (which is fully forced but free-running) have identified mesoscale eddies shed by the Florida Current as the prime forecast challenge in this domain; their life cycle properties are so regular that a targeted observing system may be in order. Options include strategically located bottom-mounted arrays of velocity profilers or upper-ocean profiling drifters, among other possibilities. Preparatory steps for OSSEs are outlined, including model-observation comparisons of correlation scales. The NRL Intra-Americas Sea -Navy Coastal Ocean Model (IAS-NCOM), a similar but fully data-assimilative nowcast/forecast system covering a much larger domain and a different grid, is evaluated as a candidate “nature run”.