Coastal Processes:

Big Sur, California

Weathering and Erosion

The coastline is shaped by action of the sea and the weather. In order to to fully understand how this happens we must first know the difference between two terms, Weathering and Erosion.

Task 1:

Follow the link above to Geographyalltheway.com and complete the worksheet at the bottom of the page.

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Waves

Waves are affected by three main factors.

• The strength of the wind

• The length of time the wind blows for

• The fetch

Constructive and Destructive Waves:

It is easy to imagine how the waves in the picture above are slowly eroding the coastline but waves can also be constructive. Waves are responsible for creating the beaches that you visit when you go to the coast.

Watch the two video’s below and you will see the difference between constructive and destructive waves.

Swash and Backwash

Constructive Waves

Destructive Waves

Summary: Waves

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Coastal Erosion

Sea stack and mount Taranaki (New Zealand)

The action of waves along the coastline can create many different landforms such as the Sea Stack in this photo. This Sea Stack is in New Zealand.

Cliff Retreat and Wave Cut Platform:

Task 2:

Go to this page from Geographyalltheway.com and complete the Coastal Erosion worksheet

Task 3:
When you have finished this you can have a go at creating an animation that shows the formation of either a sea stack or a bay. You could do this on paper, by drawing a series of pictures that you can flick through quickly or, if you able to use a computer program such as moviemaker, you could use a series of photo’s. The best animations will make up part of the museum exhibit.

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Coastal Transport and Deposition:

Longshore Drift.

Longshore drift is caused by the swash and backwash of waves. Watch the viseo below and look at pg 17 in your Geog.2 book.

Now have a go at the Google Earth task from this geographyalltheway.com page
It will introduce you to the features produced by Coastal Deposition. Pick oone of the examples of a Spit and insert a picture

KEY POINT: For deposition to take place, there must be a drop in the energy of the water. A headland is exposed to the full force of the waves and is therefore a high energy environment. A sheltered bay is protected from the force of the waves and therefore deposition can take place. It is because of this that beaches form.

Sand is simply pieces of rock that have been eroded away by the action of the waves. We are now going to look at how waves transport material.

Spit Formation:

Spits are created by deposition of sand that has been transported by longshore drift. Many of these are also incredible beaches. Click on the photo below to see more beautiful spits.

Curonian Beach Spit, Lithuania

Coastal Management: Happisbrough