coasts - seneca

Question 1

what is the littoral zone

Answer 1

series of sub zones from the sea to land. we consider it a closed system

Question 2

what are the four sub-zones in the littoral zones

Answer 2

offshore (open sea)
foreshore (land where most wave processes occur
backshore (area above high tide level that is only affected during exceptionally high tides.)

Question 3

how does a system reach dynamic equilibrium

Answer 3

input=output

Question 4

inputs of the littoral zone

Answer 4

sediment brought by waves, current and wind

Question 5

outputs of the littoral zone

Answer 5

sediment washed out to sea by erosion

Question 6

what are high energy coasts

Answer 6

destructive waves, long fetches, high erosion rates, caves, arches, stacks and stumps, cliffs and wave cut platforms

Question 7

what are low energy coasts

Answer 7

constructive waves, shorter fetches, high deposition rates, spits and bars, beaches, sand dunes and salt marshes

Question 8

how ma sediment ells are there in england & wales?

Answer 8

11

Question 9

what are the sources of sediment cells

Answer 9

where sediment comes from (cliffs, offshore bars)

Question 10

what are the flows in a sediment cells

Answer 10

movement of sediment in LSD

Question 11

what are the sinks in sediment cells

Answer 11

where sediment is deposited (spits, beaches)

Question 12

what is a positive feedback loop

Answer 12

takes system away from dynamic equilibrium

Question 13

what is a negative feedback loop

Answer 13

returning a system back to equilibrium

Question 14

negative feedback loop - a storm increases input of sediment to beach

Answer 14

• When the destructive waves from the storm lose their energy excess sediment is deposited
  as an offshore bar.
• The bar dissipates the waves energy which protects the beach from further erosion.
• Over time the bar gets eroded instead of the beach.
• Once the bar has gone normal conditions ensue and the system goes back to dynamic
  equilibrium.

Question 15

positive feedback loop - a storm increases input of sediment to beach

Answer 15

People walking over sand dunes destroys vegetation growing there and causes erosion.
- As the roots from the vegetation have been holding the sand dunes together, damaging the vegetation makes the sand dunes more susceptible to erosion. This increases the rate of
erosion.
- Eventually the sand dunes will be completely eroded leaving more of the beach open to
erosion taking the beach further away from dynamic equilibrium.

Question 16

Valentine’s Classification

Answer 16

describes the range of coastlines that can occur
An advancing coastline may be due to the land emerging or deposition being the prominent
process. Alternatively, a coastline may be retreating due to the land submerging or erosion
becoming the prominent process.
Emergent or submergent coastlines may be due to post-glacial adjustment (the land ‘wobbles’ as
the glacier above it melts, causing isostatic sea level change), as well as other causes (discussed
later).

Question 17

concordant coast

Answer 17

parallel bands to coast