Homework 9: How did Dawlish Warren form? (8 marks)

Your homework is to answer the following question:

How did the spit at Dawlish Warren form? (8 marks)

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The homework isn't finished until you have assessed your partner's work.

Mark scheme:

Level 1: Basic 1-3 marks
Knowledge of basic information about spits
Simple understanding of long shore drift
A limited range of geographical words
Limited evidence of sentence structure and frequent spelling, punctuation and grammatical errors.

Level 2: Clear 4 - 6 marks
Knowledge of accurate information about spits
Clear understanding of longshore drift
Answer uses correct terms and sentences are linked together
Some spelling, punctuation and grammatical errors.

Level 3: Detailed 7-8 marks
Knowledge of accurate information about Dawlish Warren
Detailed understanding of spit formation and longshore drift.
Uses a range of specialist terms
Well structured response with effective use of sentences and few spelling, punctuation and grammatical errors.

Remember - it's called a Spit!

(download)

Explaining the formation of beaches and spits

I think this video could be really helpful to some of you. The narrator shows how to structure an answer to explain the formation of beaches, BUT he doesn't use the GCSE level terminology of weathering, mass movement and erosion that you have been taught. Terms like freeze thaw, falling, and attrition would improve his explanation. He doesn't mention the role of waves, or the shape of the coastline. Could you do better?

The second video clip looks at the processes of deposition and transport that result in the formation of a spit.

Finally, this is a brilliant flash animation of the formation of a spit. Dawlish Warren could be a good example:

(download)

(source: Wycombe High School original author unknown)

Cliffhanger: Film about erosion at Happisburgh, Norfolk

Here's a link to the film we watched in the lesson.

This is a great case study for coastal erosion. The film illustrates how the Norfolk coastline is retreating as waves erode the base of the cliffs. Mass movement process of slumping and flowing are acting on the soft rocks. The situation is made worse because the hard sea defences are no longer being maintained by the Council. Watch the BBC clip below:

People are being affected in a number of ways. In 2005 homeowners could neither insure, nor sell their property and no compensation was available when buildings were lost. Some people could be left destitute as their homes and businesses disappeared, along with memories and community heritage. Happisburgh is important to archeologists as the oldest known site of human occupation in the UK; flint tools dating from 800,000 BP have been discovered. People are campaigning for the Government to re-build the sea defences, but their efforts seem to be in vain.

Photograph © Andrew Dunn, 04 November 2006 licensed under Creative Commons

There are several questions to think about. Is erosion more rapid in Happisburgh because of the defences built by other communities further along the coast. Happisburgh has many listed buildings and a church. Shouldn't these be protected? How much land will be lost before the Government does act? Or is it just too expensive in the long term to maintain hard defences along this stretch of coastline? Is a policy of managed retreat sustainable? The film is certainly one sided - the Coastal Concern Action Group website is here.

The latest news is that the Government have offered some compensation to peoiple who have lost their property. Is this enough?

We will lean more about sea defences and coastal management later in the course.

Coastal processes and landforms

Old Harry Rocks at Studland, near Swanage in Dorset is a good case study of landforms resulting from erosion. The video clip illustrates a headland with caves arches stacks and stumps.