coastal systems and landscapes Flashcards
shoreline management plans (SMPs)
integrated systems of coastal management introduced into the UK in 1995- there are 22 SMPs in England and Wales covering all the coastline and matching sediment cells areas
integrated coastal zone management (ICZM)
coordinated application of different policies affecting the coastal zone e.g nature protection, fisheries, industry, energy production, shipping, tourism- sustainable development via a cycle of planning, decision- making, managing and monitoring implementation, information collection
positive feedback loop
enhancement or amplification of changes; tends to move a system away from its equilibrium state and make it more unstable
negative feedback loop
dampening or buffer of changes; tends to hold a system to some equilibrium state making it more stable
dynamic equilibrium
state of balance between changing inputs and outputs over time
fetch
distance of open water over which a wind blows uninterrupted by major land obstacles- length of fetch helps determine magnitude and energy of waves
landscape
stretch of coast where related landforms combine to form a coastline with specific characteristics
constructive waves
waves with low height & frequency (6-8 per min) but long wavelength- swash more powerful than backwash so beach material increases (accretion)
destructive waves
waves with high height and frequency (10-14 per min) but steep form- backwash stronger than swash so beach material removed/ eroded
sea currents
seasonal directed movement of sea water generated by forces such as wind and the coriolis effect
neap tide
twice daily (in UK) rise and fall of the level of the sea in response to gravitational pull of the sun and moon, neap tide is lowest tidal range/ difference between high and low tide
low energy coast
coastline where wave energy is low and the rate of deposition characteristically exceeds the rate of erosion
high energy coast
coastline where strong, steady prevailing winds create high energy waves and so the rate of erosion is greater than the rae of deposition
sediment cells
distinct area of coastline separated from other areas by well-defined boundaries that hold in sediment pathways such as headlands and stretches of deep water
sediment budget
balance between sediment being added to the coast and being removed from the coast along a sediment cell stretch of coast
sub-aerial weathering
disintegration of rocks on cliff faces ‘in situ’- could be mechanical through temperature change, biological or chemical through reactions
erosion
wearing away of the surface by the mechanical movement and actions of agents or erosion e.g wind, rivers, marine waves, glaciers
mass movement
movement of material downhill under the influence of gravity- may be assisted by rainfall lubrication
hydraulic action
power of the impact of water directly onto rocks
wave quarrying/ cavitation
breaking waves trap air as they hit cliff faces and this is compressed into gaps in the rockface exerting pressure and then the pull back of water allows an explosive effect as the air pressure is released so this weakens cliff faces