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volume of sediment contained in the ebb shoals by Marino and Mehta (1986) 

 indicate addition of 6 . 3 x 10^ m^ of material from 1871-1970. The shoal 

 volume is currently about 40 . 5 x 10° m-^ . During this 99 year span, 

 relative sea level rose 0.3 m. Long-term sea level rise will also promote 

 creation of additional inlets, which affects the behavior of existing ones. 

 Each new inlet also has its own demand for sediment to maintain shoals. 



Headlands - are natural intrusions of hard material on an otherwise 

 sandy shoreline. These less-erodible features act as natural groins or 

 breakwaters and compartmentalize a shoreline. A large single isolated 

 headland usually causes a crenulate embayment to form on its downdrift 

 shoreline, as is the case at Cape Canaveral. A series of two or more 

 headlands spaced closely enough to act as a system will cause formation of 

 embayments that are more semi -circular in shape. 



The role that a headland or series of headlands will play in modifying 

 shoreline response to sea level rise will depend on the amount of incident 

 wave energy dissipated or reflected by the headland(s) , and the aspect 

 ratio (ratio of width to length) of the embayment (s) . Those with broad 

 faces parallel to the coast block significant amounts of energy, and their 

 embayments have larger aspect ratios. This means they significantly 

 increase the length of shoreline available to "resist" a given amount of 

 wave energy - the amount being controlled by the fixed distance between 

 headlands. Because of the reduced energy density at the shoreline, less of 

 the potential erosion takes place as sea level rises. This situation is 

 analogous to the performance of offshore breakwaters. However, narrow 

 headlands do not block significant amounts of wave energy and although the 

 shoreline in between may be reoriented, it is not lengthened substantially. 

 Because the energy density at the shoreline is not reduced, little is done 

 to affect on/offshore transport and therefore the full potential for 

 erosion associated with a rise in sea level can be realized. This 

 situation is analogous to a groin field, to be discussed subsequently along 

 with offshore breakwaters. 



An example of the effect of headlands on shoreline evolution is Wreck 

 Bay on the west coast of Vancouver Island, British Columbia, shown in 



