MOORED OBSERVATIONS OF THE CURRENT AND TEMPERATURE STRUCTURE OVER THECONTINENTAL-SLOPE OFF CENTRAL CALIFORNIA 1 - A BASIC DESCRIPTION OF THE VARIABILITY

Citation
Sr. Ramp et al., MOORED OBSERVATIONS OF THE CURRENT AND TEMPERATURE STRUCTURE OVER THECONTINENTAL-SLOPE OFF CENTRAL CALIFORNIA 1 - A BASIC DESCRIPTION OF THE VARIABILITY, J GEO RES-O, 102(C10), 1997, pp. 22877-22902
Citations number
68
Journal title
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
ISSN journal
21699275 → ACNP
Volume
102
Issue
C10
Year of publication
1997
Pages
22877 - 22902
Database
ISI
SICI code
2169-9275(1997)102:C10<22877:MOOTCA>2.0.ZU;2-W
Abstract
Current meter data have been analyzed from seven moorings on the conti nental slope along the central California coast, from Point Piedras Bl ancas to Point Reyes. The goal was to examine the subtidal variability in the 100 m to 1000 m depth range, particularly with regard to along shore propagating events and interactions with eddies and meanders of the California Current offshore. The 2-year time series available off Point Sur were first analyzed in conjunction with the local and remote surface wind stress and coastal synthetic subsurface pressure, and th en correlated with shorter coincident current records moored at simila r depths to the north and south. The poleward flowing California Under current was the most prominent feature at all the moorings except at o ne site located well into the Monterey Submarine Canyon. The strongest poleward flows over the slope occurred in 3- to 4-month bursts, not p hase locked with the seasons, with vector speeds exceeding 40 cm s(-1) . South of the canyon, an approximately monthly signal was identified which propagated poleward, upward, and offshore. The behavior of this signal was consistent with that of an internal coastal Kelvin wave gen erated at the surface by remote wind stress to the south and was likel y not of equatorial origin. The wave was apparently scattered by the a brupt topography of the canyon, since its energy persisted to the nort h of the canyon but with unstable phase. At least three eddy-meander i nteraction events were observed, These warm, deep (>1000 m), anticyclo nic features reversed the flow over the slope to equatorward when they moved onshore and interrupted the flow of the undercurrent, One event forced anomalously strong (>15 cm s(-1)) onshore flows off Monterey f lay and offshore flows off Point Sur. While quantitative transport est imates could not be made with this sparse data set, it seems apparent that such events play a significant role in the exchange of water prop erties between the shelf and the deep ocean.