Pt. Sal Inner Shelf Experiment (PSIEX): The Spatial and Temporal Evolution of Solitons form the Deep to the Beach

A 43-day field experiment in the summer of 2015 near Pt. Sal, California obtained cross- and alongshore measures of temperature and current throughout the water column in depths ranging from 50 m to 5 m and cross-shore distances of 6 km offshore to the edge of the surf zone around a rocky point. The high temporal and vertical resolution observations allow for a description of the evolution of the solitons as they propagate shoreward into shallow water before dissipating near the surf zone. The solitons appear to be extremely non-linear, and displace the equilibrium pycnocline depth by approximately 4-times the equilibrium pycnocline depth. While many of the solitons are found at the leading edge of semi-diurnal internal tidal waves (bores), soliton groups with varying soliton number occur throughout each day suggesting multiple source regions and temporally and spatially varying propagation pathways. The arrays are used to identify the directionality of the propagation along the coast. In addition, solitons are observed at different elevations in water column. Backscatter intensities from the acoustic Doppler current profilers will be used to describe mixing behavior.