Fig. 3. Isotherm displacements (-) showing solitons interacting with a thin layer of phytoplankton between 6 and 8 m depth, 20 June 1998. A new thin layer was spawned in the pycnocline during this period.  Colors represent fluorescence given in relative units.	Fig. 4. Profiles of volume concentration of marine snow V  and Sigma-t on 16 June 1998.  Abundance maxima occur for sigma-t of ~ 21.5 in the first two profiles; shear dispersed the flocs by 2030h.

    At 1130 and 1620 on 20 June, the maximum volume concentrations of marine snow occurred at the top of the fluorescence layer. Concentrations were high throughout the layer, and stayed high somewhat below the fluorescence maxima (Fig. 4).  However, by 2030 h, there no longer was a maximum in volume concentration.  Shear had been negligible in the pycnocline at 1930 hours, but by the time of sampling had reached values of 0.05 s^-1 between 6 and 8 m depth. Maximum energy dissipation rates had increased by an order of magnitude during this time period, and were up to 10^-6 m²s^-3.  From 1620 to 2030 h, currents showed little change in direction in the pycnocline, and as fluorescence values in the pycnocline were similar at 2000 h and 2200 h, we hypothesize that shear had disrupted the large flocs of marine snow.
 
 
 

Fluorescence Layers on June 16, note the deepening of the mixed layer, by increased wind speed. (click on image to explore June 16)

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