Beaches Flashcards
what is a beach
accumulation of sand in a low energy environment
shingle ridge
highest point of accumulation
smaller ridges are berms
gullies/runnels
depressions in beach
cusp
different types of sediment meeting
block fall
occurs on cliffs at and angle greater than 40degrees
large sections of cliff breaking off
many lithilogical features
littoral zone
backshore - sub aerial procesess, human procesess
foreshore - wave type, weather, long shore drift
open system
flamborough head SMP
no active intervention
chalk cliffs
legally protected for geological importance and internationally important habitats and wildlife
mappleton SMP
managed retread until recession reaches road
further action will be taken to sustain current level of flood risk in responding to effects of climate change
spurn head SMP
allow to develop naturally until it interferes with amount of sediment reaching humber estuary
sediment cells
11 across uk
sources, transfers, sinks
negative feedback loop - cliff erodes and protects base
positive feedbcak - damage to dunes, prevents stabalisation, futher damage
what is a sediment budget
balance between added and removed from system
happisburgh
glacial tills
groynes in 1950’s
changes in government policy, mean coastal protection is no longer fundable from central government
300m of revetment destroyed by storm
rock armour and replenishments
would take £15 mil to close gap in defences
managed relignment
Thames barrage
built to protect floodplain of greater london
operationg since 82
520m
can forecast dangerous conditions up to 3 days in advance
closed 221 times since operation
