Coasts

Question 1

What is the littoral zone?

Answer 1

Boundary between land and sea. Defined as wider coastal zone.

Question 2

Coasts are open systems, what does that mean?

Answer 2

Matter and energy can be transferred in and out of the system

Question 3

4 inputs:

Answer 3

-Marine (tides, storm surges)
-Atmospheric (climate change, solar energy)
-Land (rock type, tectonic activity)
-People ( human activity)

Question 4

5 processes:

Answer 4

-Weathering
-Mass movement
-Erosion
-Transport
-Deposition

Question 5

3 outputs:

Answer 5

-Erosional landforms (arch, stack, headland, bay)
-Depositional landforms (spits, beaches)
-Different types of coasts

Question 6

Coastal zones=

First one, Backshore
One feature of this zone:

Answer 6

Changes only during storms

Question 7

Coastal zones=

Last one, Offshore
One feature of this zone:

Answer 7

Beyond point where waves cease to impact the seabed

Question 8

4 factors that influence wave size:

Answer 8

.Fetch (distance wave has travelled)
.Wind speed
.Time wind has blown for
.Prevailing wind direction

Question 9

What are high-energy coastlines?

Answer 9

Cornwall
Very rocky due to high energy waves, only hard rock remains.
Rate of erosion is higher than deposition.
Cliffs tend to be steep with little vegetation

Question 10

What are low-energy coastlines?

Answer 10

Lincolnshire
Sandy beaches, salt marshes and estuaries with much less powerful waves.
Rate of deposition is higher than rate of erosion.
Land with gentle relief and low elevation

Question 11

3 differences between destructive and constructive waves:

Answer 11

-Destructive waves are high and constructive waves are low
-High frequency of waves for destructive and low frequency for constructive
-Strong backwash in destructive (erodes), strong swash in constructive (deposits)

Question 12

Examples for erosional landforms:

Answer 12

Headlands (Peveril Point) and bays (Swanage Bay)
Wave cut platforms
Caves, arches, stacks, stumps

Question 13

Examples of depositional landforms:

Answer 13

Spits
Salt marshes
Cuspate forelands
Double spit
Bars
Tombolos

Question 14

3 types of mass movement:

Answer 14

Landslide, material falls in straight line quickly

Rotational slumping, down curved angle

Blockfall (rockfall), broken blocks fall in steep cliff

Question 15

Different landforms caused by mass movement:

Answer 15

Rotational scar, caused by rotational slumping, bit of cliff without vegetation

Terraced cliff profile, caused by multiple rotational slumps

Talus scree slope, caused by rockfall, larger rocks fall to bottom while smaller ones are at the top

Question 16

3 types of weathering:

Answer 16

Mechanical -

Freeze thaw, wetting and drying, salt weathering

Chemical (Flamborough head cliff in Holderness) -

Carbonation, oxidation

Biological -

Plants and animals

Question 17

How does mass movement decrease rate of recession?

Answer 17

Mass movement adds rock material to beaches, strengthening beaches by increasing their size, slowing down and decreasing wave force.

Question 18

How is climate change affecting Nile delta?

Answer 18

Rising sea level is making low lying areas more saline, more difficult to farm and affects some fish species.

Question 19

What percent of Nile’s sediment does Aswan Dam hold?

Answer 19

98%

Question 20

Examples of emergent coastlines:

Answer 20

Raised beaches - West coast of Scotland
Fossil cliffs

Question 21

Examples of submergent coastlines:

Answer 21

Rias - Milford Haven in South Wales
Fjords - Norway, some over 1000 m deep
Dalmatian coastline - Croatia

Question 22

Where are there environmental refugees and where do they move to?

Answer 22

SIDS, Small Island Developing States, people in little islands like Tuvalu will move to countries unaffected by sea level rise like Australia

Question 23

Why is there political tension in Happisburgh, England?

Answer 23

Policy of managed retreat was introduced in late 90s, making the locals unhappy.

Question 24

Why did the Happisburgh residents’ protests not go their way?

Answer 24

Happisburgh did not qualify for new sea defences under the cost-benefit analysis, would have cost £15 million ( more than value of properties there).

Question 25

What actions are being made by North Norfolk District council?

Answer 25

Relocating caravan sites, public toilets and car parks
Purchasing the properties most at risk, at 40% of their value

Question 26

Case studies for each type of hard engineering strategy for coastal erosion:

Answer 26

Sea walls and groynes: Hornsea which led to increased erosion in Mappleton, by the 1990s nearly 4 meters of cliff were being eroded each year
Rock armor: Mappleton in 1991

Question 27

Disadvantages of offshore breakwaters and revetments (placed on foot of cliff)

Answer 27

Offshore breakwaters - can be navigation hazard and visually unappealing

Revetments - need high levels of maintenance

Question 28

Disadvantages of Dune stabilization and salt marsh creation (soft engineering strategies)

Answer 28

Dune stabilization - Time consuming to plant marram grass, people may respond negatively to being kept off an area too

Marsh creation - Agricultural land is lost, farmers need to be compensated

Question 29

Case study for salt marsh creation:

Answer 29

Blackwater estuary (1990s)

-3.5 km sea wall built hundreds of years ago was too expensive to maintain
-CBA showed not worth maintaining due to soil quality and land value being low
-Creeks were dug to promote formation of salt marshes
-Habitat created for Brent geese and marine invertebrates

Question 30

How are offshore bars formed?

Answer 30

Destructive waves erode sand from the beach with their strong backwash and deposit it offshore in bars

Question 31

Maldives facts:

Answer 31

-Very low lying nation that will be completely submerged within the next 50 to 100 years, 80% of land is less than 1 meter above sea level
-Maldives government asked Japanese government to give them $60 million to build 3 m sea wall to protect the capital (Male)