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Coasts. Coasts can be active or passive erosional or depositional. Parts of a beach. Wave refraction along a straight coast. The gentler the beach slope, the finer the beach sediments tend to be, as can be seen from these profiles of the Half Moon Bay, California. Elevation (ft).
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Coasts can be • active or passive • erosional or depositional
The gentler the beach slope, the finer the beach sediments tend to be, as can be seen from these profiles of the Half Moon Bay, California. Elevation (ft) Distance (ft)
Seawater temperature (°C) 2 4 6 8 10 12 14 0 June 20 March September 40 May August Depth from sea-surface (m) 60 Thermocline at the Carmel Beach is seasonal ... November 80 January 100
… and so is the beach profile. 6 August August April 3 Height above mean low water (m) September July February December June May 0 0 30 60 90 120 150 Distance from the sea cliff (m)
Seawater Temperature Winter Depth Summer Beach profile Winter Summer Sea surface Depth
These two pictures are of the same beach at Barnes Bay, Anguilla. Theone on the left was taken in 1994 …. … and the one on the right was taken sometime in 1995.
Deltas can be 1. tide-dominated, river dominated, and wave-dominated
Continental shelf, slope, and submarine canyon
How construction modifies the shoreline: • The constructing a groin or a pier, i.e., a structure perpendicular to the shoreline
How construction modifies the shoreline: • Constructing a breakwater wall means sand pile-up right behind the breakwater wall and erosion downstream