GCSE Coastal Environments Flashcards
What is a multiuse coastal environment?
An area of coastline that is used by lots of different people/groups for different reasons.
For example, walkers (social), hotel owners (economic) and birdwatchers (environmental)
What is hard engineering?
A man-made structure that is used to protect the coastline.
For example groynes, rip-rap, etc.
What is the difference between weathering and erosion?
Weathering is the breakdown of the coastline due to the weather. For example wetting and drying.
Erosion is the wearing away of the coastline due to the action of the sea. For example abrasion or hydraulic action.
What are the positives and negatives of using groynes as a form of coastal protection?
Positives
* creates a bigger beach as sand moved by LSD (longshore drift) is trapper which makes the beach bigger
Negatives
* stops sand from moving down the coast which leads to erosion further down the coast
*groynes are very expensive - around £200,000 each (and you will need more than one on a beach)
What is hydraulic action?
Is it weathering or erosion?
Hydraulic action is where the sheer force of the waves hitting again a cliff causes it to be worn away.
This is a form of erosion.
What is abrasion?
Is it weathering or erosion?
Abrasion is where sand and other materials are picked up by the waves. As the waves hit the cliff they wear it away, like sandpaper.
This is a form of erosion.
What is the difference between a destructive and a constructive wave?
A destructive wave has a strong backwash and pulls material off the beach.
A constructive wave has a stronger swash, which pushes material onto a beach making it bigger.
What is the difference between swash and backwash?
Swash is the movement of waves onto a beach. Swash enters the beach at a 45 degree angle to the coastline.
Backwash is the movement of the wave back from the beach into the sea. This is at a 90 degree angle to the coastline.
What is longshore drift?
The movement of material along a coastline, through the processes of swash and backwash. The direction of movement is decided by the wind.
What is a spit?
A spit is a coastal feature which is created by the movement of material along a coastline by longshore drift.
The material is deposited at the end of the coastline and builds up into the sea.
The direction the spit forms in is decided by the wind.
A saltmarsh often forms in the sheltered area behind.
How are caves, arches, stacks and stumps formed?
Waves crash against a cliff face, through processes such as hydraulic action and abrasion.
As this continually happens small cracks begin to appear.
Over time these cracks get bigger and form a cave.
When the cave is worn all the way through it forms an arch.
Continued erosion of the base of the arch causes the top of the arch to become too heavy so it collapses. This forms a stack.
Gradually the stack is eroded down and a stump of formed.
After this is worn away a piece of rock is left behind in the sea, which is known as a wave cut platform.
What is the difference between a headland and a bay?
A headland is an area of resistant (hard) rock that takes a long time to be eroded. These headlands were typically used to build castles and lighthouses, as they were good vantage points.
A bay is an area of less resistant (softer) rock that is eroded. This eroded area forms a sheltered beach area.
What is riprap (also known as rock armour?
How does it protect the coastline?
These are giant rocks that are placed at the bottom of a cliff.
They help to stop cliff erosion at the base, as the waves hit the rocks first reducing their erosion power.
How is Southampton an example of a multi-use coastal environment?
- It has 2 ports that are for both cargo ships and cruise liners (economic and social)
- There are many hotels, B&Bs, souvenire shops, etc. which cater for the tourists who visit this area (economic and social)
- There is a nature reserve - Lymington-Keyhaven, which is home to many rare plant and animal species (environmental)
- They have a sports activity centre which people visit to canoe, rockclimb, do archery, etc. They also have some excellent cliff walks (social)
- The Exxon Oil Refinery is a huge employer in the area and also produces lots of refined oil which is transported to other parts of the UK and northern Europe (economic and social)
How does making a beach bigger reduce coastal erosion?
A bigger beach will mean waves have to travel further before reaching the Cliffe. This will mean wave energy is dissipated (reduced) so it has less erosive power.
