• Banas, N. S., B. M. Hickey, and P. MacCready, 2004: Dynamics of Willapa Bay, Washington: A highly unsteady, partially mixed estuary. J. Phys. Oceanogr., 34, 24132427.

    • Search Google Scholar
    • Export Citation
  • Beardsley, R. C., and W. C. Boicourt, 1981: On estuarine and continental-shelf circulation in the Middle Atlantic Bight. Evolution of Physical Oceanography, B. A. Warren and C. Wunsch, Eds., MIT Press, 198–233.

  • Bowen, M. M., 2000: Mechanisms and variability of salt transport in partially stratified estuaries. Ph.D. thesis, Woods Hole/Massachusetts Institute of Technology Joint Program in Physical Oceanography, 171 pp.

  • Chatwin, P. C., 1976: Some remarks on the maintenance of the salinity distribution in estuaries. Estuarine Coastal Mar. Sci., 4, 555–566.

    • Search Google Scholar
    • Export Citation
  • Chen, S. N., W. R. Geyer, D. K. Ralston, and J. A. Lerczak, 2012: Estuarine exchange flow quantified with isohaline coordinates: Contrasting long and short estuaries. J. Phys. Oceanogr., 42, 748–763.

    • Search Google Scholar
    • Export Citation
  • Cook, T. L., C. K. Sommerfield, and K. C. Wong, 2007: Observations of tidal and springtime sediment transport in the Upper Delaware Estuary. Estuarine Coastal Shelf Sci., 72, 235246.

    • Search Google Scholar
    • Export Citation
  • Galperin, B., and G. L. Mellor, 1990: Salinity intrusion and residual circulation in Delaware bay during the drought of 1984. Estuarine Coastal Shelf Sci., 38, 469480.

    • Search Google Scholar
    • Export Citation
  • Garvine, R. W., R. K. McCarthy, and K. C. Wong, 1992: The axial salinity distribution in the Delaware Estuary and its weak response to river discharge. Estuarine Coastal Shelf Sci., 35, 157165.

    • Search Google Scholar
    • Export Citation
  • Hansen, D. V., and M. Rattray, 1965: Gravitational circulation in straits and estuaries. J. Mar. Res., 23, 104122.

  • Hansen, D. V., and M. Rattray, 1966: New dimensions in estuary classification. Limnol. Oceanogr., 3, 319326.

  • Hofmann, E., and Coauthors, 2009: Understanding how disease and environment combine to structure resistance in estuarine bivalve populations. Oceanography, 22, 212231.

    • Search Google Scholar
    • Export Citation
  • Lerczak, J. A., W. R. Geyer, and R. J. Chant, 2006: Mechanisms driving the time dependent salt flux in a partially stratified estuary. J. Phys. Oceanogr., 36, 22962311.

    • Search Google Scholar
    • Export Citation
  • MacCready, P., 2004: Toward a unified theory of tidally-averaged estuarine salinity structure. Estuaries, 27, 561570.

  • MacCready, P., 2007: Estuarine adjustment. J. Phys. Oceanogr., 37, 21332145.

  • MacCready, P., 2011: Calculating estuarine exchange flow using isohaline coordinates. J. Phys. Oceanogr., 41, 11161124.

  • McCarthy, R. K., 1991: A two-dimensional analytical model of density-driven residual currents in tidally dominated, well-mixed estuaries. Ph.D. thesis, University of Delaware, 174 pp.

  • Monismith, S. G., W. Kimmerer, J. R. Burau, and M. T. Stecey, 2002: Structure and flow-induced variability of subtidal salinity field in northern San Francisco Bay. J. Phys. Oceanogr., 32, 30033019.

    • Search Google Scholar
    • Export Citation
  • Mukai, A. Y., J. J. Westerink, J. Luettich, and D. Mark, 2002: Eastcoast 2001, A Tidal Constituent Database for Western North Atlantic, Gulf of Mexico, and Caribbean Sea. Rep. ERDC/CHL TR-02-24, U.S. Army Corps of Engineers, 196 pp. [Available online at http://www.dtic.mil/cgi-bin/GetTRDoc?Location=U2&doc=GetTRDoc.pdf&AD=ADA408733.]

  • Oey, L. Y., 1984: On steady salinity distribution and circulation in partially mixed and well mixed estuaries. J. Phys. Oceanogr., 14, 629645.

    • Search Google Scholar
    • Export Citation
  • Paulson, R. W., 1970: Variations of the longitudinal dispersion coefficient in the Delaware River Estuary as a function of fresh water inflow. Water Resour. Res., 6, 516526.

    • Search Google Scholar
    • Export Citation
  • Ralston, D. K., W. R. Geyer, and J. A. Lerczak, 2008: Subtidal salinity and velocity in the Hudson River Estuary: Observations and modeling. J. Phys. Oceanogr., 38, 753770.

    • Search Google Scholar
    • Export Citation
  • Shchepetkin, A. F., and J. C. McWilliams, 2009: Computational kernel algorithms for fine-scale, multiprocess, longtime oceanic simulations. Computational Methods for the Atmosphere and the Oceans, P. G. Ciarlet, Ed., Handbook of Numerical Analysis, Vol. 14, Elsevier, 121–183.

  • Stommel, H., and H. Farmer, 1952: On the nature of estuarine circulation. Office of Naval Research Tech. Rep. 52–88, 172 pp.

  • U.S. Army Corps of Engineers, cited 1974: The district. A history of the Philadelphia district. [Available online at http://140.194.76.129/publications/misc/un16/c-15.pdf.]

  • Warner, J., C. Sherwood, H. Arango, and R. Signell, 2005: Performance of four turbulence closure models implemented using a generic length scale method. Ocean Modell., 8, 81113.

    • Search Google Scholar
    • Export Citation
  • Whitney, M. M., and R. W. Garvine, 2006: Simulating the delaware bay buoyant flow: Comparison with observations. J. Phys. Oceanogr., 36, 321.

    • Search Google Scholar
    • Export Citation
  • Wong, K. C., and J. E. Moses-Hall, 1998: The tidal and subtidal variations in the transverse salinity and current distribution across a coastal plain estuary. J. Mar. Res., 56, 489517.

    • Search Google Scholar
    • Export Citation
  • Wong, K. W., 1994: On the nature of transverse variability in a coastal plain estuary. J. Geophys. Res., 99 (C7), 14 20914 222.

  • Zahed, F., A. Etemad-Shahidi, and E. Jabbari, 2008: Modeling of salinity intrusion under different hydrological conditions in the Arvand River Estuary. Can. J. Civ. Eng., 35, 14761480.

    • Search Google Scholar
    • Export Citation
  • Zimmerman, J., 1986: The tidal whirlpool: A review of horizontal dispersion by tidal and residual currents. Neth. J. Sea Res., 20, 133154.

    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 9 9 9
PDF Downloads 5 5 5

A Numerical Study of Salt Fluxes in Delaware Bay Estuary

View More View Less
  • 1 Rutgers, The State University of New Jersey, New Brunswick, New Jersey
Restricted access

Abstract

The results of a numerical study of Delaware Bay using the Regional Ocean Modeling System (ROMS) are presented. The simulations are run over a range of steady river inputs and used M2 and S2 tidal components to capture the spring–neap variability. Results provide a description of the spatial and temporal structure of the estuarine exchange flow and the salinity field, as well the along-channel salt flux in the estuary. The along-channel salt flux is decomposed into an advective term associated with the river flow, a steady shear dispersion Fe associated with the estuarine exchange flow, and a tidal oscillatory salt flux Ft. Time series of Fe and Ft show that both are larger during neap tide than during spring. This time variability of Ft, which is contrary to existing scalings, is caused by the lateral flows that bring velocity and salinity out of quadrature and the stronger stratification during neap tide, which causes Ft to be enhanced relative to spring tide. A fit for the salt intrusion length L with river discharge Q for a number of isohalines is performed. The functional dependences of L with Q are significantly weaker than Q−1/3 scaling. It is concluded that the response of the salt field with river discharge is due to the dependence of Fe and Ft with Q and the relative importance of Ft to the total upstream salt flux: as river discharge increases, Fe becomes the dominant mechanism. Once Fe dominates, the salt field stiffens because of a reduction of the vertical eddy viscosity with increasing Q.

Corresponding author address: María Aristizábal, Rutgers, The State University of New Jersey, New Brunswick, 71 Dudley Road, New Brunswick, NJ 08901. E-mail: aristizabal@marine.rutgers.edu

Abstract

The results of a numerical study of Delaware Bay using the Regional Ocean Modeling System (ROMS) are presented. The simulations are run over a range of steady river inputs and used M2 and S2 tidal components to capture the spring–neap variability. Results provide a description of the spatial and temporal structure of the estuarine exchange flow and the salinity field, as well the along-channel salt flux in the estuary. The along-channel salt flux is decomposed into an advective term associated with the river flow, a steady shear dispersion Fe associated with the estuarine exchange flow, and a tidal oscillatory salt flux Ft. Time series of Fe and Ft show that both are larger during neap tide than during spring. This time variability of Ft, which is contrary to existing scalings, is caused by the lateral flows that bring velocity and salinity out of quadrature and the stronger stratification during neap tide, which causes Ft to be enhanced relative to spring tide. A fit for the salt intrusion length L with river discharge Q for a number of isohalines is performed. The functional dependences of L with Q are significantly weaker than Q−1/3 scaling. It is concluded that the response of the salt field with river discharge is due to the dependence of Fe and Ft with Q and the relative importance of Ft to the total upstream salt flux: as river discharge increases, Fe becomes the dominant mechanism. Once Fe dominates, the salt field stiffens because of a reduction of the vertical eddy viscosity with increasing Q.

Corresponding author address: María Aristizábal, Rutgers, The State University of New Jersey, New Brunswick, 71 Dudley Road, New Brunswick, NJ 08901. E-mail: aristizabal@marine.rutgers.edu
Save