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Robert C. Beardsley

Publications and source records attributed to Robert C. Beardsley.

4 recordsLinked to original sources
USGS2012

Effect of wave-current interaction on wind-driven circulation in narrow, shallow embayments

The effect of wind waves on the steady wind-driven circulation in a narrow, shallow bay is investigated with a two-dimensional ( y , z ) circulation model and the Grant and Madsen [1979] bottom-boundary layer model, which includes wave-current interaction. A constant wind stress is applied in the along-channel x direction to a channel with a constant cross-sectional profile h ( y ). The wind-induced flushing of shallow bays is shown to be sensitive to both the shape of the cross section and the effects of surface waves. The flushing increases with increasing , where h ′ is the standard deviation of cross-channel depth and is the mean depth. This is consistent with the findings of Hearn et al. [1987]. The flushing decreases, however, with the inclusion of surface wave effects which act to increase the bottom drag felt by the currents. Increasing effective bottom friction reduces the strength of the circulation, while the along-bay surface slope, bottom stress and the structure of current profiles remain nearly unchanged. An implication of the circulation dependence on wave-current interaction is that low-frequency oscillatory winds may drive a mean circulation when the wave field changes with wind direction. x

Journal of Geophysical Research C: Oceans↗
USGS2010

Physical oceanography of continental shelves

Knowledge of the physical oceanography of continental shelves has increased tremendously in recent years, primarily as a result of new current and hydrographic measurements made in locations where no comparable measurements existed previously. In general, observations from geographically distinct continental shelves have shown that the nature of the flow may vary considerably from region to region. Although some characteristics, such as the response of currents to wind forcing, are common to many shelves, the relative importance of various physical processes in influencing the shelf flow field frequently is different. In the last several years, the scientific literature on shelf studies has expanded rapidly, with that for separate regions, to some extent, developing independently because of the variable role played by different physical effects.

Reviews of Geophysics and Space Physics↗
USGS2006

The Massachusetts Bay internal wave experiment, August 1998: Data report

This data report presents oceanographic observations made in Massachusetts Bay (fig. 1) in August 1998 as part of the Massachusetts Bay Internal Wave Experiment (MBIWE98). MBIWE98 was carried out to characterize large-amplitude internal waves in Massachusetts Bay and to investigate the possible resuspension and transport of bottom sediments caused by these waves. This data report presents a description of the field program and instrumentation, an overview of the data through summary plots and statistics, and the time-series data in NetCDF format. The objective of this report is to make the data available in digital form and to provide summary plots and statistics to facilitate browsing of the data set. The existence of large-amplitude internal waves in Massachusetts Bay was first described by Halpern (1971). In summer when the water is stratified, packets of waves propagate westward into the bay on the flood (westward flowing) tide at about 0.5 m/s. The internal waves are observed in packets of 5-10 waves, have periods of 5-10 minutes and wavelengths of 200-400 m, and cause downward excursions of the thermocline of as much as 30 m. The waves are generated by interaction of the barotropic tide with Stellwagen Bank (Haury and others (1979). Several papers present analyses and interpretations of the data collected during the MBIWE98. Grosenbaugh and others (2002) report on the results of the horizontal array, Scotti and others (2005) describe a strategy for processing observations made by Acoustic Doppler Current Profilers (ADCPs) in the presence of short-wavelength internal waves, Butman and others (in press) describe the effect of these waves on sediment transport, and Scotti and others (in press) describe the energetics of the internal waves.

Massachusetts↗