CASPER West IOP: Observations of Semi-Diurnal Tides and Diurnal Ocean Mixed Layer Variability

During the CASPER West IOP (23 Sep - 05 Nov 2017), two AUV gliders, ship-based and FLIP-based observations were used to characterize the semi-diurnal and dirunal variability of the upper ocean. Strong semi-diurnal internal tidal variability was observed with large vertical displacements, strong vertical shear and intense turbulent mixing. Diurnal variability in the surface layer followed a pattern of heating during the day and cooling during the night. We observed coupling between the two signals with the internal tides modifying the diurnal response of the surface mixed layer.