changes occur over very short-time periods, e.g., inlets through barrier 

 islands have opened up in a matter of hours during storms. These same 

 inlets were observed closing in a matter of weeks or months. Complete 

 beaches have eroded away within a few years due either to natural pro- 

 cesses or the influence of man; other beaches have formed in as much time. 

 In addition to one-time changes, there are changes such as seasonal 

 variations in beach width, steady growth of spits and hooks, and migra- 

 tions of capes and inlets. 



Because changes to coastal landforms are continuous and often rapid, 

 maps of these areas become obsolete very quickly. With repeated coverage 

 by satellite imagery, the problem of obsolescence inherent in current 

 methods of mapping can be eliminated. Photos obtained from satellite 

 imagery can provide an up-to-date supplement to existing maps, and with 

 repeated coverage over relatively short-time intervals, a means of moni- 

 toring changes that are occurring in landforms, as long as those changes 

 are large enough to be resolved by satellite sensors. 



This section discusses the morphological changes that have occurred 

 in each of the five sites along the coast of North Carolina: Carolina 

 Beach, Carolina Beach Inlet, Masonboro Beach, Masonboro Inlet, and 

 Wrightsville Beach. Emphasis has been placed on the comparison of what 

 was observed in the ERTS-1 imagery to low altitude aerial photography and 

 ground- truth data. 



Blowups of the study area obtained from the first and last ERTS-1 

 films analyzed (30 July 1972 and 2 June 1973) are shown in Figures 8 and 

 9. Band 7 in Figure 8 has an overlay of the land-water interface traced 

 directly from band 7 in Figure 9, allowing direct comparison of shoreline 

 change between the two dates. Comparison of the two ERTS-1 films was 

 made with a Zoom Transfer Scope (Ambrose and McHail, 1972). Figure 10 

 shows mosaics of underflight infrared color photos of the study area on 

 19 July 1972 and 15 June 1973. The following discussion relates directly 

 to Figures 8 to 11. The location map in Figure 1 should be used to pin- 

 point locations of the various features. 



1. Carolina Beach . 



Comparison of the two underflight mosaics (Figs. 10 and 11) shows that 

 significant erosion occurred along the arched part of Carolina Beach, 

 immediately south of Carolina Beach Inlet. This shoreline recession was 

 more apparent in the ERTS-1 photos than in the underflight mosaics because 

 of the lower image resolution and scan-line distortion in ERTS-1 imagery. 

 No erosion was apparent along the beach south of the arched part. A 

 report by the U.S. Army Engineer District, Wilmington (1970) stated that 

 before the opening of Carolina Beach Inlet in 1952, the now-curved part 

 of Carolina Beach was continuous with the shoreline to the south and 

 Masonboro Beach to the north. Subsequent erosion of the segment imme- 

 diately south of the inlet has been in progress since the opening of the 

 inlet. This erosion was a natural development resulting from a deficit of 

 littoral drift from the north, caused by material entrapment in the inlet. 



