Ocean Dynamics

, Volume 62, Issue 5, pp 771–784 | Cite as

The coupled Hudson River estuarine-plume response to variable wind and river forcings

Article
Part of the following topical collections:
  1. Topical Collection on Physics of Estuaries and Coastal Seas 2010

Abstract

Observations of the Hudson River plume were taken in the spring of 2006 in conjunction with the Lagrangian Transport and Transformation Experiment using mooring arrays, shipboard observations, and satellite data. During this time period, the plume was subjected to a variety of wind, buoyant, and shelf forcings, which yield vastly different responses in plume structure including a downstream recirculating eddy. During weak and downwelling winds, the plume formed a narrow buoyant coastal current that propagated downstream near the internal wave speed. Freshwater transport during periods when the downwelling wind was closely aligned with the coast was near the river discharge values. During periods with a cross-shore component to the wind, freshwater transport in the coastal current estimated by the mooring array is less than the river discharge due to a widening of the plume that leads to the internal Rossby radius scaling for the plume width to be invalid. The offshore detachment of plume and formation of a downstream eddy that is observed surprisingly persisted for 2 weeks under a variety of wind forcing conditions. Comparison between mooring, shipboard, and satellite data reveal the downstream eddy is steady in time. Shipboard transects yield a freshwater content equal to the previous 3 days of river discharge. The feature itself was formed due to a large discharge following a strong onshore wind. The plume was then further modified by a brief upwelling wind and currents influenced by the Hudson Shelf Valley. The duration of the detachment and downstream eddy can be explained using a Wedderburn number which is largely consistent with the wind strength index described by Whitney and Garvine (J Geophys Res 110:C03014 1997).

Keywords

Buoyant river plume Estuary-coastal ocean coupling Coastal freshwater transport Hudson River 

Notes

Acknowledgements

We would like to acknowledge the helpful comments from an anonymous reviewer, Eli Hunter and Chip Haldeman for their mooring work, Brad Butman for the HSV moorings, and support from the Institute of Marine and Coastal Scinces at Rutgers University and NSF awards OCE-0238957, OCE-0825833, and OCE-0928567.

References

  1. Avicola G, Huq P (2003) The characteristics of the recirculating bulge region in coastal buoyant outflows. J Mar Res 61:435–463CrossRefGoogle Scholar
  2. Castelao R, Schofield O, Glenn S, Chant R, Kohut J (2008) Cross-shelf transport of freshwater on the New Jersey shelf. J Geophys Res 113:C07017. doi: 10.1029/2007JC004241 CrossRefGoogle Scholar
  3. Chant RJ, Glenn SM, Hunter E, Kohut J, Chen RF, Houghton RW, Bosch J, Schofield O (2008) Bulge formation of a buoyant river outflow. J Geophys Res 113:C01717. doi: 10.1029/2007JC004100 CrossRefGoogle Scholar
  4. Chen S-N, Sanford P (2009) Axial wind effects on stratification and longitudinal salt transport in an idealized, partially mixed estuary. J Phys Oceanogr 39:1905–1920CrossRefGoogle Scholar
  5. Choi BJ, Wilkin JL (2007) The effect of wind on the dispersal of the Hudson River plume. J Phys Oceanogr 24:1878–1896CrossRefGoogle Scholar
  6. Fong DA, Geyer WR (2001) Response of a river plume during an upwelling favorable wind event. J Geophys Res 106:1067–1084CrossRefGoogle Scholar
  7. Fong DA, Geyer WR (2002) The alongshore transport of freshwater in a surface-trapped river plume. J Phys Oceanogr 32:957–972CrossRefGoogle Scholar
  8. Fong DA, Geyer WR, Signell RP (1997) The wind-forced response on a buoyant coastal current: observations of the western Gulf of Maine plume. J Mar Syst 12:69–81CrossRefGoogle Scholar
  9. Garvine RW (1985) A simple model of estuarine subtidal fluctuations forced by local and remote wind stress. J Geophys Res 90:11945–11948CrossRefGoogle Scholar
  10. Garvine RW (1995) A dynamical system for classifying buoyant discharges. Cont Shelf Res 15:1585–1596CrossRefGoogle Scholar
  11. Geyer WR (1997) Influence of wind on dynamics and flushing of shallow estuaries. Estuar Coast Shelf Science 44:713–22Google Scholar
  12. Harris CK, Butman B, Traykovski P (2003) Winter-time circulation and sedimaent transport in the Hudson Shelf Valley. Cont Shelf Res 23:801–820CrossRefGoogle Scholar
  13. Hetland RD (2005) Relating river plume structure to vertical mixing. J Phys Oceanogr 35:1667–1668CrossRefGoogle Scholar
  14. Horner-Devine AR (2009) The bulge circulation in the Columbia River plume. Cont Shelf Res 29:234–251CrossRefGoogle Scholar
  15. Horner-Devine AR, Fong DA, Monosmtih SG, Maxworthy T (2006) Laboratory experiments simulating a coast river inflow. J Fluid Mech 555:203–232CrossRefGoogle Scholar
  16. Huq P (2009) The role of Kelvin number on bulge formation from estuarine buoyant outflows. Estuaries Coasts 32:709–719CrossRefGoogle Scholar
  17. Lentz SJ (2004) The response of buoyant coastal plumes to upwelling favorable winds. J Phys Oceanogr 43:2458–2469CrossRefGoogle Scholar
  18. Lentz SJ (2008) Observations and a model of the mean circulation over the Middle Atlantic Bight continental shelf. J Phys Oceanogr 38:1203–1221CrossRefGoogle Scholar
  19. Lentz SJ, Helfrich KR (2002) Buoyant gravity currents along a sloping bottom in a rotating fluid. J Fluid Mech 464:251–278CrossRefGoogle Scholar
  20. Lentz SJ, Largier J (2006) The influence of wind forcing on the Chesapeake Bay coastal current. J Phys Oceanogr 36:1305–1316CrossRefGoogle Scholar
  21. Lerczak JA, Geyer WR, Ralston DK (2009) The temporal response of the length of a partially stratified estuary to changes in river flow and tidal amplitude. J Phys Oceanogr 39:915–933CrossRefGoogle Scholar
  22. Monismith S (1987) Modal response of reservoirs to wind stress. J Hydraulic Eng 113:1290–1306CrossRefGoogle Scholar
  23. Münchow A, Chant RJ (2000) Kinematics of inner shelf motions during the summer stratified season off New Jersey. J Phys Oceanogr 30:247–268CrossRefGoogle Scholar
  24. Ralston DK, Geyer WR, Lerczak JA (2008) Subtidal salinity and velocity in the Hudson River estuary: observation and modeling. J Phys Oceanogr 38:753–770CrossRefGoogle Scholar
  25. Rennie SE, Largier JL, Lentz SJ (1999) Observations of a pulsed buoyancy current downstream of Chesapeake Bay. J Geophys Res 104:18227–18240CrossRefGoogle Scholar
  26. Thompson RORY, Imberger J (1980) Response of a numerical model of a stratified lake to winds stress. Proc 2nd Int Symp on stratified flows, Trondhiem, Norway 1:562–570Google Scholar
  27. Valle-Levinson A, Lwiza KMM (1995) The effects of channels and shoals on exchange between the Chesapeake Bay and the adjacent ocean. J Geophys Res 100:18551–18563CrossRefGoogle Scholar
  28. Whitney MM, Garvine RW (1997) Wind influence on a coastal buoyant outflow. J Geophys Res 110:C03014. doi: 10.1029/2003JC002261 CrossRefGoogle Scholar
  29. Yankovsky AE, Chapman DC (1997) A simple theory for the fate of buoyant discharges. J Phys Oceanogr 27:1386–1401CrossRefGoogle Scholar
  30. Yankovsky AE, Garvine RW (1998) Subinertial dynamice on the inner New Jersey shelf during the upwelling season. J Phys Oceanogr 28:2444–2458CrossRefGoogle Scholar
  31. Yankovsky AE, Hickey BM, Münchow AK (2001) Impact of variable inflow in the dynamics of a coastal buoyant plume. J Geophys Res 106:19809–19824CrossRefGoogle Scholar
  32. Zhang WG, Wilkin JL, Chant RJ (2009) Modeling the pathways and mean dynamics of river plume dispersal in the New York Bight. J Phys Oceanogr 39:1167–1183CrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2012

Authors and Affiliations

  1. 1.Institute of Marine and Coastal SciencesRutgers UniversityNew BrunswickUSA

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