| Temperature data from southern Monterey Bay reveal frequent solitons and semidiurnal internal tidal bores on the inner shelf. We undertook a field study to determine whether these features originate offshore and propagate shoreward over the continental shelf, and to characterize their evolution as they propagate. We sampled internal waves of various scales on the outer and mid-shelf during five surveys, using an autonomous underwater vehicle programmed for thermocline tracking and rapid, repeated CTD profiling. Internal tidal bores of amplitude greater than 20 meters propagating eastward from the outer bay were the dominant feature. Short period steep solitons appeared, propagated, and dissipated over the shelf without a definite pattern. Changes in stratification due to horizontal advection and atmospheric forcing appeared to affect internal wave generation and propagation on hourly to seasonal timescales. This may explain the high spatial and temporal variability of internal waves on the shelf. |
