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mid 1970s, comprehensive surveys have been conducted on approximately a 

 decadal basis and post-storm studies carried out when appropriate. This 

 type of system provides the only basis for obtaining quality information of 

 shoreline change. It would be very worthwhile, in anticipation of the 

 rising concern over shoreline response to sea level rise, to encourage 

 other states to install, monitor and maintain a monumented system similar 

 to that of Florida. 



Evidence from the Continental Shelf - The seafloor of the continental 

 shelf contains information relating to past shoreline response to sea level 

 rise and potential future response. Specifically, Swift (1975) has shown 

 that along much of the Mid-Atlantic Region, there is a "lagoonal carpet" of 

 muds that could not contribute significantly to the sediment budget of the 

 active shoreface. Additionally, the shape of the offshore profiles, along 

 with the availability of sand- sized material contains information (although 

 as yet not completely understood) whether the offshore profile will serve 

 as a source or sink of sand. 



In addition to the above, it would be worthwhile to conduct 

 measurements of long-term sediment movement on the continental shelf. 

 These measurements would be conducted along a representative profile; they 

 would document the forcing function (waves, currents, tides, stresses, 

 etc.) and sediment transport (response function). The sediment transport 

 woijild best be documented through passive means, such as the use of sediment 

 tracing techniques . 



7.4.3 New Technology 



Laser Profiling - A laser profiling system has been developed in which 

 the airborne laser oscillates in a conical pattern thereby sweeping out a 

 swath of one -half the airplane height, with the ground level pattern being 

 nearly circular overlapping trajectories. The laser return establishes the 

 dry beach elevation, the water surface and the below water profile to 

 approximately two "secchi" disk depths. The potential of this technology 

 to systematically and periodically conduct regional and tidally controlled 

 surveys of shoreline change is extremely encouraging. It is recommended 

 that a pilot program be conducted in Florida in the coming year. 



