ABSTRACT

Temporal variability observed in several time series of suspended matter measurements, obtained by light scattering and conventional water sampling, has been examined to identify significant time scales with respect to synoptic characterization of regional suspended matter distributions in the inner New York Bight. Processes with periods corresponding to surface waves (seconds) and storms (days) apparently make the strongest contributions to overall concentration variability, and tidal motions appear to have only a weak influence on near-bottom suspended load. An empirical model is proposed which assumes that concentration variance is linearly related to the mean concentration, both increasing in response to such processes as wind-wave mixing and boundary layer interactions with the b ttom. Data obtained during the study support the model. This model is used in a numerical experiment which suggests that fair-weather variability in processes affecting near-bottom concentrations is probably not sufficient to cause serious errors in suspended matter studies in the New York Bight.