PRINCIPAL 



INVESTIGATOR(S) Leonard J. Pietrafesa 



Department of Marine, Earth, and Atmospheric Science 



P.O. Box 8208 



North Carolina State University 



Raleigh, NC 27695 



PROJECT TITLE SEDIMENT MOTIONS AND BOTTOM BOUNDARY LAYER 



DYNAMICS OVER THE MIDDLE ATLANTIC BIGHT SHELF 

 AND UPPER SLOPE 



AMOUNT OF FUNDING FY 1994: $221 K 



SUMMARY OF GOALS 



LJ. Pietrafesa is presently conducting pilot studies of sediment dynamics over the Middle 

 Atlantic Bight (MAB) in the vicinity of the Cape Hatteras Confluence (CHC) including the 

 mouths of estuaries, the shelf and the slope, as part of the Department of Energy Ocean Margins 

 Program in concert with G. Weatherly (FSU) and J. Churchill and S. Williams (WHOI). Being 

 studied are processes which effect sediment motion and in particular, the processes which 

 determine rates of vertical transport of dissolved carbon dioxide and organic matter and 

 particulates to and from the bottom by turbulent mixing resuspension and particulate sinking and 

 vertical motions induced by BBL convergences; especially during periods of storm activity when 

 both surface waves and currents are maxima. 



SPATIAL AND TEMPORAL SAMPLING SCALES 



SPATIAL 



a. Vertical 



1. Benthic Boundary Layer (Several tens of centimeters to meters) 



2. Surface Boundary Layer (Meters to tens of meters) 



3. Estuarine Circulation and Plumes (Meters to tens of meters) 



4. Internal Waves (Meters to several tens of meters) 



5. Surface Gravity Waves (Meters to less than two hundred meters) 



6. Fronts (Tens to hundreds of meters) 



7. Subinertial Frequency currents (Tens to hundreds of meters) 



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