Tidally induced turbulence and suspended sediment

نویسندگان

  • Alejandro J. Souza
  • Luis G. Alvarez
  • Tommy D. Dickey
چکیده

[1] Nearly continuous data collected using novel methods are utilized to advance the understanding of turbulence and suspended particulate matter (SPM) dynamics under strong tidal flow conditions. Key instrumentation includes a single acoustic current profiler that provides nearly continuous, concurrent turbulence and SPM information with respect to depth near the seafloor and within the water column. Observations show a lag of about 1 hour in turbulence production between the bottom and 12 meters above the bottom (mab), and of about 1.5 hours for SPM. Estimates of eddy viscosity show values ranging between 10 3 and 10 2 m s , with an almost constant mean value of 3.5 10 3 m s 1 within the bottom 7 meters. The present observations and a previously reported theory show good agreement in both amplitude and phase for SPM and turbulence, when values of eddy viscosity ranging between 3.5 10 3 (mean) and 10 2 (maximum) are used. Our data set is valuable for evaluating, developing, and improving turbulence and SPM numerical models.

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تاریخ انتشار 2004