HF surface current radar (CODAR) data from two shore-based radar sites were collected and combined to form vector estimates of the near-surface currents in Monterey Bay from March to May 1992. CODAR-derived currents are measures of the flow in the upper 1 m of the water column. The springtime mean flow pattern in the Bay and it's variability based on a maximum of 760 three-hourly observations at a nominal 2 km spatial resolution are presented. Results for each month and the canonical day are also shown. The mean patterns show strong southward flowing onshore currents (=20 cm.s(-1)) in the outer bay and near zero mean flow nearshore and northwest of Moss Landing. The variability is, however, large with standard deviations typically twice the mean. The canonical day shows strong (=4- cm.s(-1)) onshore flow over the entire Bay in the late nighttime period. These flow patterns combine to produce the observed mean flow. CODAR data show energy at a semi-diurnal tidal periods (12.3 and 11.9 hours), diurnal period (24 hours) and a longer period (17 days). CODAR data is compared to data from a moored buoy. Low-passed time series are well correlated. Unfiltered time series have higher correlations at diurnal and semidiurnal tidal frequencies. CODAR-derived surface currents and the winds are highly correlated at Near-diurnal frequencies corresponding to the daily sea breeze forcing.

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http://archive.org/details/analysisofmonter1094523532

Lieutenant, United States Navy