PHYSICAL AND BIO-OPTICAL PROCESSES IN THE GULF OF MEXICO – LINKING REAL- REALTIME CIRCULATION MODELS AND SATELLITE BIO-OPTICAL AND SST PROPERTIES*

摘要

Ocean circulation is shown to influence the bio-optical properties in open and coastal waters in the Gulf of Mexico. Three dimensional physical ocean properties of temperature, salinity, and currents determined from the Navy Coastal Ocean Model (NCOM) are being combined with daily “latest pixel composite” satellite properties (phytoplankton, CDOM and detritus absorption and backscattering and SST). The coupling of these data sources provides supportive evidence of the degree which physical processes influence bio-optical processes in the surface ocean. NCOM assimilates daily SST along with synthetic temperature and salinity profiles from MODAS and is forced by surface COAMPS winds. Ocean color and SST from SeaWIFS and MODIS (Terra and Aqua) provide daily real-time observations. We demonstrate the response of the Mississippi River plume (observed through bio-optical signatures), to coastal advection and eddy circulation. We observe that divergent and convergent regions in the model show a strong bio-optical response (growth and decay of phytoplankton) in the imagery. Furthermore, particle tracking in the model is used to follow different river discharges and track the corresponding bio-optical response in the imagery. The combined model and imagery analyses provide new methods to extend the limitations of models and imagery when analyzed individually. These include model validation of ocean features and extending the surface satellite properties to include subsurface processes. Lastly, we applied time inversion of particle tracking from the models to show the source waters where satellite observed phytoplankton blooms originated. Using effective methods, these combined data sources provide new tools for coastal managers in assessing and predicting HABS, hypoxia and freshwaters impacts