Thursday, 12 December 2013

Factors that influence..

The factors can be divided in three : primary, secondary and tertiary factors. 

Primary factors
•The hardness or ‘erodibility’ of sea-facing rocks is controlled by the rock strength and the
presence of fissures, fractures, and beds of non-cohesive materials such as silt and fine sand.
•The rate at which cliff fall debris is removed from the foreshore depends on the power of the
waves crossing the beach. This energy must reach a critical level to remove material from
the debris lobe. Debris lobes can be very persistent and can take many years to completely
disappear.

•Beaches dissipate wave energy on the foreshore and provide a measure of protection to the
adjoining land.
The stability of the foreshore, or its resistance to lowering. Once stable, the foreshore should
widen and become more effective at dissipating the wave energy, so that fewer and less
powerful waves reach beyond it. The provision of updrift material coming onto the foreshore
beneath the cliff helps ensure a stable beach.
The configuration of the seafloor, controls the wave energy arriving at the coast, and can
have an important influence on the rate of cliff erosion. Shoals and bars offer protection from
wave erosion by causing storm waves to break and dissipate their energy before reaching
the shore. Given the dynamic nature of the seafloor, changes in the location of shoals and
bars may cause the locus of beach or cliff erosion to change position along the shore.
•Coastal erosion has been greatly affected by the rising sea levels globally.  

Secondary factors
Weathering and transport slope processes
Slope hydrology
Vegetation
Cliff foot erosion
Cliff foot sediment accumulation
Resistance of cliff foot sediment to attrition and transport
Human Activity

 Tertiary factors
Resource extraction
Coastal management

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