The wave climate at a particular beach also determines the effect 

 a storm will have. In a high-energy climate, storm waves are not much 

 larger than ordinary waves, and their effects may not be significant. An 

 example of this might be northeasters occurring at Cape Cod. In a low- 

 energy wave climate, where transport volumes are usually low, storm waves 

 can move significant amounts of sand, as do hurricanes on the gulf coast. 



The type of beach sediment is also important in storm-induced changes. 

 A storm can uncover sediments not ordinarily exposed to wave action, and 

 thus alter the processes that follow the storm. (Morgan, et al., 1958.) 

 In sand-deficient areas where the beach is underlain by mud, the effects 

 of a storm can be severe and permanent. 



The effects of particular storms on certain beaches are described in 

 the following paragraphs. These examples illustrate how an extreme event 

 may affect the beach. 



In October 1963, the worst storm in the memory of the Eskimo people 

 occurred over an ice-free part of the Arctic Ocean, and attacked the coast 

 near Barrow, Alaska. (Hume and Schalk, 1967.) Detailed measurements of 

 some of the key coastal areas had been made just before the storm. Freeze- 

 up just after the storm preserved the changes to the beach until surveys 

 could be made the following July. Most of the beaches accreted 1 to 2 

 feet, although Point Barrow was turned into an island. According to Hume 

 and Schalk, "The storm of 1963 would appear to have added to the Point the 

 sediment of at least 20 years of normal longshore transport." Because of 

 the low-energy wave climate and the short season in which littoral pro- 

 cesses can occur at Barrow, this storm significantly modified the beach. 



A study of two hurricanes, Carla (1961) and Cindy (1963), was made by 

 Hayes (1967). He concluded that "the importance of catastrophic storms 

 as sediment movers cannot be over-emphasized," and observed that, in low- 

 energy wave climates, most of the total energy is expended in the near- 

 shore zone as a series of catastrophes. In this region, however, the rare 

 "extreme" hurricane is probably not as significant in making net changes 

 as the more frequent moderate hurricanes. 



Surprisingly, Hurricane Camille, with mEiximum winds of 200 mph, did 

 not cause significant changes to the beaches of Mississippi and Louisiana. 

 Tanner (1970) estimated that the sand transport along the beach appeared 

 to have been an amount equal to less than a year's amount under ordinary 

 conditions, and theorized that "the particular configuration of beach, sea 

 wall, and coastal ridge tended to suppress large scale transport." 



Hurricane Audrey struck the western coast of Louisiana in June, 1957. 

 The changes to the beach during the storm were not extreme nor permanent. 

 However, the storm exposed marsh sediments in areas where sand was defi- 

 cient, and "set the stage for a period of rapid shoreline retreat follow- 

 ing the storm." (Morgan, et al., 1958.) Indirectly, then, the storm was 

 responsible for significant geomorphic change. 



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