1. ADCP-BASED VARIANCE METHOD REYNOLDS STRESS ESTIMATES IN A TIDELESS ESTUARY Harvey Seim, Rick Luettich, Luke Stearns, (Tony Whipple) Department of Marine Sciences and Institute of Marine Sciences, University of North Carolina at Chapel Hill

2. ADCP configurations Mode 1 30 cm bins +10 m range 600 pings/ensemble 2 ensembles/hour Tidally-dominated 2.5 m/s peak current Mode 5 10 cm bins ~5m range 900 pings/ensemble 2 ensembles/hour Non-tidal environment 25 cm/s peak current

4. - B.I.

5. Along- Channel shear Turbulent production B.I.

6. (1.3 and 2.1 x 10 -3 ) B.I.

7. Neuse River

8. N.R.

12. - -

15. 1-2 mab 3-4 mab 4-5 mab u’w’ q2q2

16. 5 mab 3 mab 1 mab Can stresses be ‘corrected’ for tilt?

17. Summary Mode 5 works well in this low energy environment for mean currents Remarkable Ri structure at 10 cm scales Reynolds stresses appear too energetic – tilt angle too large? Exploring corrections but doesn’t look good