Ocean color and infrared imagery from aircraft and satellite sensors are combined with in situ measurements of currents, chlorophyll, temperature, salinity, coastal winds, and sea level to study upwelling events in the Georgia Bight where the Gulf Stream and continental shelf waters strongly interact. These interactions were observed over an 8 day period in April 1980 during which five independent upwelling occurrred. The upwelling included a nearshore wind-driven upwelling enhanced by topographic effects, three Gulf Stream filament-induced upwelling, and what appears to have been a Gulf Stream meander-induced event. The chlorophyll distributions as inferred from the imagery are found to be reliable tracers which indicate filamentary circulation and propagation and advective routes by which near shore water moves offshore. The propagation of two of the filaments and the meander are studied in detail using the imagery and mooring array temperature time series. Both techniques yield nearly identical results for the phase speeds of each event. There is evidence that one of the filaments accelerated as it entered into the Charleston Bump area where the Gulf Stream deflects offshore. The other filament exhibited a steady deceleration as it moved past Cape Canaveral and eventually lost any semblance of wave motion. Also included are data from April 1979 which offer corroborating evidence of filamentary structure and circulation. Intercomparisons field measurements and the Nimbus 7/coastal zone color scanner estimates of surface pigment concentrations show excellent agreement over the range 0.1--7.0 mg/m3. |