Coastal Systems

Question 1

Fetch

Answer 1

the sea distance over which the wind travels to produce waves

Question 2

Swash

Answer 2

the landward flow of water

Question 3

Backwash

Answer 3

the seaward flow of water down a beach

Question 4

Accretion

Answer 4

the growth of a natural feature by enlargement

Question 5

Psammosere

Answer 5

the succession of plants that develop on a sand dune (sea rocket, lyme grass and marram grass)

Question 6

Eustatic change

Answer 6

sea level change that affects the globe (glacial melt)

Question 7

Isostatic change

Answer 7

sea level change affecting localised areas

Question 8

Groynes

Answer 8

timber or rock structures built at right angles to the coastline

Question 9

Hold the line (SMP)

Answer 9

maintaining or upgrading level of protection

Question 10

No active intervention (SMP)

Answer 10

‘do nothing’

Question 11

Advance the line (SMP)

Answer 11

building new defences seaward of the existing defence line

Question 12

Management realignment (SMP)

Answer 12

allowing retreat of the shoreline with management to control or limit movement

Question 13

Gabions

Answer 13

hard engineering method - wire cages filled with small rocks, often used to support week cliffs

Question 14

Revetments

Answer 14

hard engineering method - wooden barriers in a slat like form placed at the base of a cliff or top of a beach

Question 15

Beach cusps

Answer 15

small semi circle depressions in sand and single on swash aligned beaches

Question 16

Ripples

Answer 16

micro beach ridges parallel to the shoreline

Question 17

Ridges and runnels

Answer 17

alternate raised and dip sections that run parallel to the shoreline, exposed at low tide

Question 18

Destructive wave characteristics

Answer 18

short wavelengths, greater height and more frequent (10-14 per minute)

Question 19

Constructive wave characteristics

Answer 19

longer wavelengths, lower heights and less frequent (6-8 per minute)

Question 20

When does salt weathering happen?

Answer 20

when rocks become saturated with water

Question 21

Chemical weathering processes?

Answer 21

Involves the decay or decomposition of rock, water acts as a dilute acid. Tends to increase with rising temperatures and humidity as carbonic and limestone react as a greater rate.

Question 22

Name the 3 sub-zones of a beach with a description of each

Answer 22

offshore - beyond the breaking waves area
Nearshore - inter tidal and within the breaker zone
Backshore - above the influence of normal wave patterns

Question 23

Tombolo

Answer 23

when two spits join the mainland at one end of the island together

Question 24

Spits

Answer 24

long, narrow stretches of sand or shingle that protrude into the sea or across an estuary

Question 25

Concordant coastlines

Answer 25

layers of hard and soft rock run parallel to the coast (depositional landforms)

Question 26

Discordant coastlines

Answer 26

layers of hard and soft rock run perpendicular to the coastline, at 90 degrees (erosional landforms)

Question 27

abrasion is:

Answer 27

As waves break on the shore, the water, stones and the energy of the waves cause erosion.

Question 28

hydraulic action

Answer 28

as water is forced into small cracks by waves, pressure builds, and when the water leaves, the pressure is released. this process repeated over time weakens rock

Question 29

attrition

Answer 29

when pebbles hit each other and become smooth over time as sharp edges are ‘knocked off’ through collisions with other pebbles