Tuvalu is located at 8°31’S and 179°11’E in south Pacific Ocean with the capitol on Fongafale Island in Funafuti Atoll. On October 21, 1972, Tropical Cyclone Bebe hit Funafuti Atoll, and during the cyclone a large amount of coral debris was deposited on the reef flat (Maragos et al., 1973; Baines et al., 1974). Although this example shows that coral islets could be developed by storm waves during cyclones, the formation and deformation of the rampart on the reef flat and resulting deformation of the coral islets are important in the conservation of the atoll, when future sea level rise is considered. The long-term shoreline changes in Funafuti Atoll was investigated by using aerial photographs in 1971 and 1984, and satellite image in 2010. Also the photographs of the formation of the rampart immediately after Tropical Cyclone Bebe were collected. On June 6, 2012, site observations were carried out on Fatato, Funangongo and Funamanu Islands located southwest of Fongafale Island, as well as the beach surveys using a total station at the east and west ends of Funamanu Island on June 12 and 13, 2012. Maragos et al. (1973) concluded that although severe tropical cyclones may be considered to be infrequent phenomena, from a geological time perspective, they may play a significant role in the accretion and formation of atoll islets. In fact, coral debris was transported shoreward due to wave action, and this rampart was becoming incorporated into the fabric of Funafuti (Nunn, 1994). However, it was concluded that the net increase in atoll islets is small, suggesting that almost all coral debris was lost due to the southwestward longshore transport along the reef edge in the long period, and finally they are assumed to have been fallen into reef gap.
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