185 LEATHERMAN, S. P. 1983(a). "Barrier Dynamics and Landward Migration 

 With Holocene Sea-Level Rise," Nature . Vol 301, No. 5899, pp 415-418. 



Barrier beaches (islands and spits) have become the subject of mounting 

 interest due to human development on these landf orms . It is commonly thought 

 that barrier beaches continuously migrate landward in response to sea- level 

 rise, often by overwash processes, maintain mass through time, and that these 

 processes are occurring at a rate commensurate with human (100 year) time 

 frames. While some barriers are naturally migrating quite rapidly, other 

 barriers decidedly are not. Here the author presents data which illustrate 

 that many U.S. Atlantic Coast barriers are not evolving over the short term in 

 accordance with generally accepted hypotheses and argue that the presumed norm 

 may actually be the exception. (Author) . 



186 LEATHERMAN, S. P. 1983(b). "Barrier Island Evolution in Response to 

 Sea-Level Rise: A Discussion," Journal of Sedimentary Petrology . Vol 53, 

 No. 3, pp 1025-1033. 



During sea- level rise, barrier islands are forced landward with shore- 

 face retreat. While retreat rate is dependent upon the balance between 

 sediment supply and sea-level change, continuous migration, probably inter- 

 mittent at times, as opposed to barrier overstepping, is clearly favored for 

 low coastal plain barriers. Barrier drowning and subsequent surf -zone skip- 

 ping are theoretically possible, but evidence to date from the New York shelf 

 is not convincing. Barrier islands along the U.S. Atlantic and Gulf Coasts 

 can be expected to migrate continuously landward with sea- level rise. 

 Exhumation of pre-Holocene or partially consolidated sediments on the shelf 

 surface with transgression can minimize but not prohibit barrier retreat. 

 (Summary) . 



187 LEATHERMAN, S. P. 1983(c). "Geomorphic Effects of Projected Sea-Level 

 Rise: A Case Study of Galveston Bay, Texas," Proceedings of Coastal Zone '83. 

 Third Symposium on Coastal and Ocean Management . Vol III, pp 2890-2901. 



This paper describes a study of the geomorphic effects of projected sea- 

 level rise on low-lying coastal landforms along southeast Galveston Bay, 

 Texas. The area selected for this pilot study, a portion of the Gulf coastal 

 plain, is quite low and gently slopes seaward. Therefore, a slight vertical 

 rise in sea-level results in significant horizontal displacement of the shore- 

 line and storm surge envelope. Other selection criteria included the follow- 

 ing: microtidal environment, major Gulf Coast estuary, highly developed cen- 

 ters at Texas City and north Galveston Island, availability of the National 

 Weather Service storm surge model (SLOSH) , and information on historical ero- 

 sional trends and subsidence data. 



Three sea- level rise scenarios were generated by the Environmental 

 Protection Agency (EPA) ; nine rise/year combinations were selected from the 

 projected sea- level rise curves. Table 1 represents the algebraic sum of the 

 projected sea-level rise and subsidence. The table indicates, for example, 

 without an accelerated rise in sea- level (i.e., the baseline scenario), by 



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