Littoral Drift Estimates Along The Coastline Of Florida PDF Download

A 4.5-year series of daily and weekly littoral environment observations and beach profile surveys was made at 3 localities in Southeastern Florida. As a result of varying protection by the Bahamas Banks, the amount of wave energy reaching the shoreline decreases from north to south. Mean annual breaker height decreases from a maximum of 2.8 ft at Jupiter on the north to a minimum of 1.6 ft at Hollywood on the south. A pronounced seasonal variation is evident with waves and currents from the southeasterly sector dominating during April through September. Monthly averages of breaker height and period data were the same for a 4.5-year set of daily observations and a subset of weekly observations. Potential gross longshore transport rates, estimated using these wave data, ranged from 2,300,000 cu yd/yr at Jupiter to 400,000 cu yd/yr at Hollywood. The magnitude of beach changes decreased from north to south and was low compared to changes on more exposed beaches on the U.S. east coast. Contributing factors include the sheltering effect of the Bahamas Banks, the lack of significant storms, and the underlying coquina limestone which characteristically crops out just below the MSL shoreline at the two sites with the highest waves, forming a protective reef that effectively retards beach erosion.