Coastal erosion - Mappleton Flashcards
Where is Mappleton?
On the Holderness Coast, East Yorkshire, which is in North East England.
The Holderness Coast is number one in Europe for what?
Fastest eroding coastline! In an average year, 7 - 10 metres of land are removed by the waves, along unprotected parts of the coast.
What has happened since Roman times?
3 - 4 KM of coastline has been lost, with 29 villages lost in the last 1000 years.
Why is the rate of erosion so high?
A combination of land sinking on the east coast and sea level rise, which is bringing waves further up the cliff, has been combined with weak cliffs made of soft boulder clay, deposited by glaciation. The cliffs are also prone to landslides and rotational slip.
How fast are the sea levels rising here?`
4mm a year.
It is hard to protect a stretch of coastline that is over 50km long, so why choose Mappleton?
In Mappleton, the B1242 - a vital coastal road that links villages together - is closest to the cliffs. To protect Mappleton was cheaper than to reroute the road.
£2 million was spent protecting a road and a village with 100 residents… but what did they get for this money?
A rock groyne, stretching out into the sea and some rock armour along the cliff line. This was all made of Norwegian granite, a very hard wearing rock.
Why use a groyne?
The groyne is designed to stop long shore drift, catching material and making the beach wider. In turn, this means there is more natural protection between the waves and the cliffs, reducing wave energy and therefore erosion.
Has the groyne been successful?
Yes, to a point - it has slowed erosion North of the groyne dramatically, securing the future of the village and the road.
However, to the south, with less beach material arriving, the beach has become narrower and erosion has sped up - to a massive metre a month!
How have people to the south of the groyne been affected?
Farmland is being lost; businesses are failing. The nearby caravan site has been forced to shut for safety reasons. Residents cannot get house insurance because it is a question of when, not if, there house falls into the sea - equally no one wants to buy their house so they are stuck!
