Coasts

Question 1

Why are coasts important and how they are used?

Answer 1

Tourism: many resorts along coasts
Sports: many sports use the coast like sailing, surfing
Fishing: oceans are full of fish - catching and selling fish.
Transport: oceans are used to transport people and goods

Question 2

Why are coasts under threat?

Answer 2

• Sea level rise
• Litter. Litter thrown into the sea can also kill animals. Turtles often mistake plastic bags for jellyfish.
  Over fishing: many fish stocks around the world are being over fished to dangerous levels.

Question 3

Define swash

Answer 3

The movement of water and load up the beach

Question 4

Define backwash

Answer 4

The movement of water and load back down the beach

Question 5

Describe destructive waves

Answer 5

A weak swash - because the wave breaks almost vertically

A strong backwash. It erode and transport material from beaches

Question 6

Describe constructive waves

Answer 6

Strong swash and weak backwash because they tend to deposit material and build beaches up.

Question 7

Compare destructive waves and constructive waves

Answer 7

Destructive waves: high wave in length

Constructive waves: low wave in length

Question 8

Define bay

Answer 8

An indented area of land normally found between two headlands. Bays are usually more sheltered so there is less erosive power, meaning you often find beaches in bays.

Question 9

Define headland

Answer 9

A piece of land that sticks out into the sea. Waves refract around headlands so they experience a lot of erosion forming features like arches and stacks .

Question 10

What are the conditions for coral reefs to live?

Answer 10

• Tropical sea conditions
• Warm waters
• Sunlight
• No pollution

Question 11

Describe fringing reef

Answer 11

They fringe the coastline or islands. They are often protected by barrier reefs further out to sea, so the plants and animals that live in fringing reefs are suited to low wave energy environments.

Question 12

Describe barrier reef

Answer 12

These occur further from the sea and are commonly separated from the mainland or island by a deep lagoon. Barrier reefs are normally older and wider than fringing reefs

Question 13

Describe atoll

Answer 13

They rise from submerged volcanoes. They are similar to barrier reefs in terms of biodiversity and form. However, they are confined to submerged oceanic islands

Question 14

Describe benefits of coral reefs( physical)

Answer 14

• Protect coastlines from erosion
• Support 25% of marine species
• Form as a natural barrier against tropical storms
• Source of raw material (coral for jewelry)

Question 15

Describe coral reef management

Answer 15

• Conservation zones where tourists aren’t allowed
• Reduce the use of fertilizers near coral reefs
• Educating people why coral reefs are important and how we can protect them

Question 16

Describe longshore drift

Answer 16

• When waves approach the coast at an angle the
swash moves up the beach at an angle.
• The backwash,however, drains straight back down
the beach.
• This will gradually move sand/stones along the beach in a zig-zag motion.

Question 17

Describe the process of cliff and wave-cut platform

Answer 17

• Wave erosion is concentrated at the foot of the cliff so a wave-cut notch is formed.
• The cliff is undercut & collapses.
• Repeated collapse causes retreat of the cliff producing a platform of flat rock at the cliff foot extending out to sea.

Question 18

Describe the process of beaches

Answer 18

In bays the waves diverge outwards. The wave energy is dissipated
creating a low energy environment hence deposition to form beaches.

Question 19

Describe the process of bays and headlands

Answer 19

• Bays are formed due to softer rock getting eroded easily.

* Headlands are usually formed since they are made of resistant rock and so is eroded more difficultly.

Question 20

Describe the process of spits

Answer 20

• Spits form when the coastline changes direction. Longshore drift continues to carry material in the same direction.
• Sand & shingle is built up to form the spit.
• The end of the spit curves round due to wave refraction or secondary winds.

Question 21

Describe the process of sand dunes

Answer 21

• Sand dunes form behind wide sandy beaches.
• Onshore winds pick up the dry sand from above the high-water mark & carry it landward by saltation.
• If they encounter an obstacle the wind loses energy & deposits sand in the lee of the obstacle.

Question 22

Describe the process of salt marsh

Answer 22

• Mud is deposited by the tides. The beach builds up above sea level forming mudflats.
• Plants start to grow in the mud & trap more sediment. This forms into a salt marsh.