PRINCIPAL 



INVESTIGATOR(S) Charles N. Flagg 



Oceanographic and Atmospheric Sciences Division 



Building 318 



Brookhaven National Laboratory 



Upton, NY 19973 



PROJECT TITLE COASTAL TRANSPORT AND DIFFUSION 



AMOUNT OF FUNDING FY 1994: $208 K 



SUMMARY OF GOALS 



1. To understand the genesis of the low frequency baroclinic pressure field and its role in the 

 generation of the low frequency baroclinic currents. The goal is to use monthly averaged 

 temperature, salinity, and current data from moorings together with hydrographic survey results 

 to look at the balance of terms in the very low-frequency momentum and mass conservation 

 equations, and thus better understand the factors controlling the seasonal mean currents. 



2. To further our understanding of the bio-physical interactions on the shelf. SEEP-II 

 demonstrated that we could measure phytoplankton and zooplankton biomasses with some degree 

 of accuracy over long periods. The use of a three-dimensional array of sensors should make it 

 possible to unravel this convolution of processes over intermediate to large scales, and to study 

 more directly the impact that mixing and shear have on the biological processes. This kind of 

 study should also make it possible to study the spatial structure of the phytoplankton and 

 zooplankton fields. 



3. To study the kinematics and dynamics of the frontal eddies and filaments with the intent to 

 quantify the cross-frontal transport that results from these possibly dominant processes. These 

 features collectively may be responsible for the majority of the cross- frontal transport of mass, 

 and suspended and dissolved constituents. These difficulties, however, can be quite simply 

 addressed by satellite directed sampling with synoptic hydrographic surveys and TOYO/Seasoar 

 high speed sampling. 



SPATIAL AND TEMPORAL SAMPLING SCALES 



1. The mean cross-isobath current shears observed in SEEP-II suggest isopycnal slopes of 

 between 6x10^ to 10' 5 . The high isopycnal slopes apply to winter and sub-thermocline summer 

 conditions. The lower slope values apply to the summer thermocline. With a sufficient vertical 

 array of SEACATS to measure temperature and conductivity, the higher slope, (10 cm/km), 



40 



