The 20-year mean of the total discharge shows a seasonal low of 1000 m3/s in autumn and a maximum of 4000 m3/s in spring. The maximum discharge was over 7000 m3/s during the high discharge year like 1993.
The inner shelf of the SAB is dominated by tidal motion. M2 tidal currents are about 30 to 40 cm/s near the coastal area, which account for about 80 to 90% (cross-shelf) and about 20 to 40% (along-shelf) current variation and kinetic energy in the inner shelf. Tidal energy is largest in the widest part of the shelf between Savannah and South Carolina and smallest at northern and southern ends.
The climatology of wind fields over the SAB can be divided into five seasons: winter (November to February), spring (March to May), summer (June to July), fall (August), and mariners’ fall (September to October). The entire shelf of the SAB is characterized by northwesterly, northerly, or northeasterly wind in winder and by southeasterly or southwesterly wind in summer. Spring and fall seasons are in the transitional regime, which is typically by a relatively weak wind except during atmospheric frontal passages. In mariners’ fall, the northeasterly wind, which is strongest for entire year prevails over the entire SAB.
Our modeling efforts on the SAB started in late 90’s, with focus on physical processes associated with the low-salinity front and cross-frontal water exchange over the inner shelf of the SAB (Chen et al., 1999; Chen 2000). These works were conducted originally using the modified version of the Princeton Ocean Model (called ECOM-si) (Blumberg and Mellor, 1987), and recently updated by using our own developed unstructured grid, finite-volume coastal ocean model (FVCOM). A brief summary is given here to provide the information about our accomplishments in this region.
Our research activities are supported by the Georgia Sea Grant College Program. Because the Sea Grant is focused on estuaries, we are searching for additional funds to continue to develop an operational coupled atmosphere-ocean-ecosystem model system for the SAB. Our door is opening for collaboration.
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