Currents in Monterey Submarine Canyon.

Abstract

Time series were obtained from two current meters near bottom on one mooring in Monterey Submarine Canyon. These records were analyzed to determine the general character of the currents, the volume transport at different levels above the canyon floor, the power spectral estimates of the up-canyon and cross-canyon directional components, and the coherence between directional components. Current speed variations appeared as a series of peaks occurring every 5 to 6 hr with maxima of 17 to 21 cm/sec. Current directions oscillated with a discernible period of about 12 hr. Currents 30 m above the bottom were aligned nearly along the canyon axis; currents 60 m above the bottom were nearly perpendicular to the canyon axis. The spectral analysis indicated tides as a major driving force of the deep currents, but also indicated the presence of other forcing functions, possibly internal waves, with shorter periods. The coherence between instruments was low, suggesting the possible presence of a near-bottom boundary layer, or that significant signal deterioration was caused by noise.