Coastal Systems And Landscapes

Question 1

What do the energy obtained by wind depend on?

Answer 1

Wind velocity
Length of fetch
Time wind has blown
Depth of water

Question 2

How does wind create waves?

Answer 2

Friction on the top of the water. The wind picks up and carries the water

Question 3

What is positive feedback?

Answer 3

Amplifies the effect.

Question 4

What is negative feedback?

Answer 4

Nullifies the effect

Question 5

What features do constructive waves have?

Answer 5

Depositional
Short fetch
Low
Swash>backwash
Long
Less frequent

Question 6

What features do destructive waves have?

Answer 6

Destroy beaches
Strong
Backwash>swash
Scour beaches
Tall waves
Frequent

Question 7

How are constructive waves formed?

Answer 7

Approaches beach slowly , gently spills onto beach surface
Swash loses volume nd energy
Water percolates through beach material as has time to do so
Backwash weak so no material removed from besch

Question 8

What do constructive waves form?

Answer 8

Ridges and berms

Long less steep beaches

Question 9

What happens with destructive waves?

Answer 9

Rapidly steepen and plunge down when breaking
Backwash> 
Inhibits Swash of next wave
Little material moved up
B wash pulls material down

Question 10

What type of beach do destructive waves form

Answer 10

Steep

Question 11

What is wave refraction

Answer 11

Irregular coastline
Waves slow at shallower water around headland
Headland waves refract around and all orthogonals (wave directions) converge =erode
Waves in deeper water towards bay Cary on going quickly. Reduction in energy nd deposit
LSD carries mat. From h into b

Question 12

What controls the tides?

Answer 12

Grav pull of sun and moon
Moon pulls water towards it creating high tides - bulge on other side too.
Areas in between tides are low

Question 13

What are spring tides

Answer 13

Twice a month. Sun moon and earth in straight line. Tide raising force is strongest
Higher high tides and lower low tides = HIGHEST MONTHLY TIDAL RANGE

Question 14

What are neap tides

Answer 14

Twice a month earth90° in relation to sun and moon.
Lower high tides, higher low tides
Lowest monthly tidal range

Question 15

What are the 3 types of current

Answer 15

LSD- waves hitting coast at an angle and transport material along coast
Rip- currents moving away from coast
Upwelling

Question 16

What are sediment cells

Answer 16

Movement of sand and shingle sized sediment by LSD. 11 sediment cells and sediment stays in those areas

Question 17

What are some erosional processes

Answer 17

Hydraulic action- force of water into rocks. Cavitation occurs with the loss of pressure s air bubbles come out nd can create shockwaves
Abrasion- hurled against cliffs
Wave pounding- mass of water is powerful

Question 18

What are some weathering processes

Answer 18

Freeze thaw
Solution - dissolved minerals react with water then the rocks
Carbonation- co2 in rain reacting with rocks like limestone and chalk to create bicarbonates which react with water

Question 19

Formation of cliffs and wave cut platforms

Answer 19

D waves
Erosion close to high tide line
Wave cut notch
Continued e
Under cut, upper part of cliff collapses (over hang) - weathering
Cliff retreats
Mat. Used to erode again or transported elsewhere

Question 20

How are geos caves arches stacks and stumps and blowholes formed

Answer 20

D waved attack line of weakness
E into cracks
Widening crack to form narrow steep sided inlet- a geo
Widening horizontally = cave
Erosion continues upwards to top of cave- water rises up creating a blowhole
E all way through= arch
Arch collapse over time- weathering creating a stack
More e to create a stump