Fluorescence structure in the region of the tidal mixing front on the southern flank of Georges Bank

Transects of fluorescence measurements were made across the region of the tidal-mixing front on the southern flank of Georges Bank in 1992, 1993 and 1994. The fluorescence distribution exhibited three characteristic patterns: (i) a subsurface maximum associated with the pycnocline in stratified water columns; (ii) a spatially incoherent variability with a characteristic spectral slope, believed to be related to the local vertical mixing processes; and (iii) a higher level of fluorescence within the front on some transects. This latter pattern was observed when the tidal current amplitude had recently increased with the local fortnightly/monthly variability.