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Coastal (Protection) Structures
Miyazaki PrefectureNovember 07, 2007
PANTAI
PANTAI
PELINDUNG PANTAI
PELINDUNG PANTAI
PELINDUNG PANTAI
Night scene of the earth— What this indicates?
http://veimages.gsfc.nasa.gov/1438/earth_lights_lrg.jpg
Earth at Night by C. Mayhew & R. Simmon (NASA/GSFC), NOAA/NGDC, DMSP Digital Archive
Night scene—What this means ?
http://veimages.gsfc.nasa.gov/1438/earth_lights_lrg.jpg
http://veimages.gsfc.nasa.gov/116/pop_density.jpgPopulation density(NASA)
Concentration of humans and assets
Earth at Night by C. Mayhew & R. Simmon (NASA/GSFC), NOAA/NGDC, DMSP Digital Archive
Concentration of population and assets
(possibility of catastrophic disasters) 人口・資産の集中（大災害の可能性）
Advancement of civilization
(strong? / vulnerable? against disasters)文明の発展（災害に強い ?逆に脆弱）
Energy consumption(accelerating global
warming)エネルギーの消費（温暖化に荷担）
Storm surge: Yokohama, 2007
Coastal Protections Needed
Coastal Protections Needed
Ten years after the constructionof the Narrowneck Reef, Australia
Coastal Protections Needed
Miami Beach
Before
After
Five Generic Solutions
Contoh Kasus: Holbeck Hall, Scarborough,North Yorkshire, England
Why does cliff recession occur?What are the effects of cliff recession?How can the coastline be protected?What are the disadvantages of coastal protection?What is the best method of coastal protection?
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Why does cliff recession occur?
Why does cliff recession occur?What are the effects of cliff recession?How can the coastline be protected?What are the disadvantages of coastal protection?What is the best method of coastal protection?
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What are the effects of cliff recession?
Why does cliff recession occur?What are the effects of cliff recession?How can the coastline be protected?What are the disadvantages of coastal protection?What is the best method of coastal protection?
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How can the coastline be protected?
How do groynes work?
Groynes trap the sand which is carried along the coast by longshore drift.
The sand acts as a natural protection against the force of the waves. The waves break on the beach and not the cliffs.
How can the coastline be protected?
Hard engineering techniques aim to stop coastal processes from occurring. Soft engineering methods try to work with nature to protect the coast.
What has been done to protect coastal areas?
Match the correct protection method to its purpose!
Why does cliff recession occur?What are the effects of cliff recession?How can the coastline be protected?What are the disadvantages of coastal protection?What is the best method of coastal protection?
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TUJUAN
What problems do sea walls create?
Why might a sea wall cause more coastal erosion?
What are the disadvantages of groynes?
In 1991 a rock revetment and two rock groynes were built. Sand accumulated and halted erosion.
South of Mappleton the rate of erosion has increased significantly.
Material that usually moves south via longshore drift is becoming trapped within the groynes.
Now there is no beach to protect the cliffs - the sea reaches the base of the soft cliffs and erosion occurs.
Mappleton is located on the Holderness Coastline.
Why does cliff recession occur?What are the effects of cliff recession?How can the coastline be protected?What are the disadvantages of coastal protection?What is the best method of coastal protection?
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What is the best method of coastal protection?
This is the imaginary coastal town of ‘Seaview’. Seaview has been suffering from coastal erosion for the last 15 years since the nearby larger town of ‘Engleton’ had groynes built to protect its own coastline.
What is the best method of coastal protection?
There are strong feelings about what should be done to protect Seaview!
Give each scheme a score from 1 (poor) to 5 (good). For example, an expensive scheme should have a low score.
Would you choose the scheme with the highest score? Why?
Which is the most important criteria?
What is the best method of coastal protection?
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