Cliff Collapse is the continuous erosion of the cliff face by the sea. The
hydraulic action of the waves and the process of abrasion undercut the cliff
to form an overhang, which eventually collapses, meaning the cliff recedes.
Coastal Figures
From Deposition
Beach
Area of sand built
up by the swash of
constructive waves
Spit
Build up of sand out at sea
by longshore drift when
coastline changes direction.
Bar
When longshore drift continues, to
join two headlands, cutting off a
bay, a strip of land is formed.
From Erosion
Headland - hard
rock jutting out at
sea.
Bay - soft rock
between 2 headlands
easily eroded to form
curved shape.
Cliff - a vertical wall
of rock bordering
the sea.
Caves, Arches, Stacks
and Stumps - formed
from continuous erosion
from the sea.
Coastal Management
Gabions - collection of
pebbles in cage. Reduce
impact of wave on the cliff.
Cheap but not long-lasting.
Revetments - slanted wood
planks that prevents cliff being
undercut. Cheap, will rot and so
are ineffective
Rock Armour - huge boulders
placed to reduce impact of
waves before a sea-wall. Cheap
but ineffective in a big storm.
Sea Groyne - Wooden or rock
fencing that sticks out at right
angles to the coast to prevent
longshore drift. Effectively protects
beach, quite cheap but look ugly
and can starve downcoast of sand.
Curved Sea Wall - reflects wave
power to protect the cliff/land.
Very effective, last a long time
but quite expensive
Breakwater - Huge concrete blocks
out at sea to reduce impact of wave
before hitting beach. Produces more
constructive waves than destructive.
Very effective, last a long time but
very expensive.
Beach Replenishment - soft
engineering involving building up a
beach with more sand. Looks
natural, prevents beach eroding
quickly, but quite expensive and is
a continuous process.
Managed Retreat -
Simply doing nothing,
allowing that area of
coast to erode. Avoids
all issues but we lose
land and people lose
homes etc.
Sea Level Rise
As a result of global warming, sea level is rising. The
greenhouse gases warm the earth by trapping heat from
the sun, causing the ice to melt and sea level to rise
along with increased risk of flooding.