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ACCRETION Deposition
of sediment, usually sand, which is evident by the seaward advance
of a shoreline indicator, such as the high water line, berm crest,
or vegetation line. Accretion causes
the beach to become wider. Opposite of erosion.
AEOLIAN Transport
and deposition of sand by wind; the principal means by which sand
dunes are formed.
ALONGSHORE CURRENT
See LONGSHORE
CURRENT.
ARMORING
Placement of fixed engineering structures,
typically rock, wood timbers, or concrete, on or along the shoreline
to reduce coastal erosion. Armoring structures include seawalls,
revetments, bulkheads, and rip rap.
BACKSHORE
Generally dry portion of the beach
between the berm crest and the vegetation line that is submerged
only during high water levels and eroded during storm events.
BACKWASH
The seaward return flow of swash
on the beach face due to gravity.
BAR
Submerged mound of sand that generally runs
parallel to the shore and causes waves to break before reaching
the beach.
BARRIER BEACH A
low-lying, sandy island or spit that lies offshore and generally
parallel to the mainland.
BEACH
Accumulation of wave-deposited, loose
sediment, usually sand, that extends from the outermost breakers
to the landward limit of wave and swash action.
BEACH LOSS Volumetric
loss of sand, usually measured by a loss of dry beach width.
BEACH MONITORING
Periodic collection of data, such as dry
beach width, to study changes over time.
BEACH NARROWING Decrease
in usable (dry) beach width caused by episodic storm impact or long-term
erosion.
BEACH NOURISHMENT
Sand artificially placed on the beach, usually
by pumping sea bottom sediments onshore, to replace that being lost
alongshore or offshore. Beach nourishment projects are usually large
scale, spanning many miles of shoreline to rebuild eroded beaches.
BEACH PROFILE Measurement
of the elevation or height of the beach surface taken along a line
that runs from the dune to the water across the beach. Profiles
taken at different dates can
be compared to illustrate and quantify storm, seasonal, and longer-term
changes in beach width, height, volume, and shape.
BERM
Feature usually located at mid-beach and
characterized by a sharp break in slope, separating the flatter
backshore from the seaward-sloping foreshore.
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