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The CfA Space Geodesy Homepage Sea Level Hazards: Increased flood and storm damage Increased salinity of estuaries and aquifers This webpage was created by Stacey Archfield |
Beach erosion
The IPCC reports that 1 cm rise in sea level erodes beaches about 1 m horizontally. This becomes a large issue for developed beaches that are less than 5 m from the ocean [IPCC, 1998]. In addition, rising sea level would create larger storm surges that would quicken the rate of beach erosion; an intense storm can erode enough shore to change its entire profile in one year [Dubois, 1990]. Dubois’'s research has shown that observed values of beach erosion were two to three times greater than the erosion predicted for that year. Dubois suggests that Bruun’'s theory and rising sea level may the primary force responsible for observed erosional rates [Dubois, 1990]. Bruun's rule states that a typical concave-upward beach profile erodes sand from the beachface and deposits it offshore to maintain constant water depth [Dubois, 1990]. Bruun’'s rule can be applied to correlate sea level rise with eroding beaches. With present rates of sea level rise, 70% of the world’'s sandy beaches are eroding and retreating. If the rate of sea level rise continues to increase, the loss of beach to coastal erosion will increase.