FIGURE 1-5 



EVOLUTION OF A MARSH AS SEA LEVEL RISES 



5000 Years Ago 



-Sea Level 



B 



Today 



Sedimentation and 

 Peat Formation 



Current 

 *— Sea Level 



Past 

 Sea Level 



C Future 



Substantial Wetland Loss Where There is Vacant Upland 



Future 



2— Sea Level 



Current 

 Sea Level 



Future 



Complete Wetland Loss Where House is Protected 

 in Response to Rise in Sea Level 



<L 



Future 

 . Sea Level 



Current 

 Sea Level 



Coastal marshes have kept pace with the slow rate of sea level rise that has characterized the 

 last several thousand years. Thus, the area of marsh has expanded over time as new lands were 

 inundated, resulting in much more wetland acreage than dry land just above the wetlands (A and 

 B). If in the future, sea level rises faster than the ability of the marsh to keep pace, the marsh 

 area will contract (C). Construction of bulkheads to protect economic development may prevent 

 new marsh from forming and result in a total loss of marsh in some areas (D). 



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