coasts as natural systems Flashcards
how to describe coast
open system
dynamic
constantly changing (temporal change) - land lost by erosion and land created by deposition
coast inputs
energy:
-wave
-wind
-tide
-current
sediment
geology
seal level
what does beach dynamic equilibrium involve
supply sediment
energy of waves
change sea level
determines grow or erode
eg short term
BEACHY HEAD
longer lower angle beach
chalk cliff retreated
extended coastline
eg long temp
HOLDERNESS
29 village lost since roman
clay so easy dissolve
65’ to 95’ - 2m lost a year
what affects zone of interaction
type wave
type rock
storm
vegetation
weathering
natural disasters
what affects shape coastline
land:
-geology
-tectonics
atmosphere:
-climate
-solar energy
marine:
-tides
-waves
human:
-sea defences
-tourism
-pollution
-buildings
coastal system
input:
-energy
-sediment
-human activity
-sea level change
process:
- LSD
- erosion
-deposit
output:
-erosional landform
-depositional landform
-loss wave energy
-accumulation sediment
4 coastal zones + other
backshore
foreshore
inshore
offshore
nearshore
what is backshore
area between HWM + landward limit marine activity
marine processes only in storm
what is foreshore
area between HWM + LWM
lots marine processes here
what is inshore
area between LWM + point waves dont impact land beneath them
what is offshore
area beyond point where waves dont impact land beneath them
activity limited to deposition
what is nearshore
area extending seaward from HWM to area waves begin to break
includes:
-swash zone
-surf zone
-breaker zone
what is swash zone
area where turbulent water washes up beach
