A Beach Profile Model for a Barred Coast-Case Study front Sand Key, West-Central Florida


  • Ping Wang
  • Richard A. Davis, Jr.


Barred beach profile, beach profile modeling, cross-shore sediment transport, equilibrium beach profile, west Florida coast


A three-segment beach profile model which is capable of reproducing the commonly observed bar and trough features was developed and calibrated with 122 measured profiles from Sand Key, Florida. The bar and trough features are important parts of a nearshore equilibrium system due to their dynamic response to both short-term and long-term changes of wave-conditions. The beach profile is divided into three independent segments: inner surf zone, landward slope of breakpoint-bar, and nearshore zone (seaward from the bar top). The commonly used h = A1x 2/3 form describes the inner surf zone well. The landward side of the bar is described by a plane slope. The nearshore portion of the beach profile is describe by another power function in the form of h = A2(x - x2)m2. The parameter, x2, which is related to the distance from the shoreline to the bar top, is introduced to link the inner surf and nearshore portions. The scale parameters A1 and A2 are related to sediment grain size and its distribution. The present model requires the input of two elements of morphological information for subdividing the profile into the three segments. They are the distances from the shoreline to the trough bottom (x tr) and the bar top (xbt). A set of empirical formulas was developed for the barred coasts along the west-central Florida. The empirical parameters obtained from the Florida Gulf coast are rather different from those obtained from the Pacific coast in southern California, indicating a significant regional geological and oceanographic control.