To appear: Proc. 8th Conf. on Estuarine and Coastal Modeling, ASCE, 2004.
Coupled Circulation, Wave, and Morphology-Change Modeling,
Shinnecock Inlet, New York
Frank S. Buonaiuto, and 2Adele Militello
Analysis of five high-resolution bathymetric data sets collected at Shinnecock
Inlet, NY indicates the evolution of ebb shoal morphology between 1994 and 2000
was primarily controlled by migration of the main navigation channel. Increased
wave activity during the 1997 El Nino accelerated the rate at which the channel was
deflected toward the west. These bathymetric data are applied in this study for
assessment of morphology change calculation conducted within the Inlet Modeling
System developed by the U.S. Army Corps of Engineers Coastal Inlets Research
Program. Circulation, sediment transport, and morphology change were calculated
by the two-dimensional finite-difference model M2D, which was coupled with
STWave for computation of wave-driven currents. A simulation was conducted for
August to November 1997 in which waves from NDBC Station 44025 were input as
forcing for STWave. Tidal forcing for M2D was prescribed with water levels
extracted from a regional ADCIRC model. Major observed changes in inlet
morphology were reproduced by the modeling system. These changes are: scour and
westward migration of the navigation channel, accretion along the eastern flank of the
ebb shoal, and accretion of the seaward extent of the ebb shoal.
Shinnecock Inlet, located on the south shore of Long Island, New York (Fig. 1),
opened on September 21, 1938 during the passage of the Great New England
Hurricane (Morang 1999). Since its opening, inlet evolution has been influenced by
storms, dredging, beach nourishment projects, and construction and rehabilitation of
two offset rubble-mound jetties originally built between 1953 and 1954. Morphology
of the inlet and ebb shoal is controlled by tide and wave-driven transport, as well as
by jetties and bathymetric features such as channels and shoals. Tide on the south
shore of Long Island is semidiurnal with a mean range of 0.88 m at the inlet entrance
(ocean side). Spring tide range is 1.1 m and the tidal prism is 3.29 x 107 m3 (Militello
and Kraus 2001). Incident waves have average height of approximately 1 m and
1) Coastal Oceanographer. Marine Sciences Research Center, SUNY at Stony Brook, Stony
Brook NY 11794-5000. firstname.lastname@example.org.
2) Physical Oceanographer. Coastal Analysis LLC, 4886 Herron Road, Eureka, CA 95503.