Holderness Coast Case Study Flashcards
Where is the Holderness Coast and what is the number and name of the SMP?
North-East England, from Flamborough Head to Spurn Head
SMP 3: East Riding of Yorkshire
Why does the Holderness Coast erode rapidly?
think in terms of geology
- GEOLOGY:
FLAMBOROUGH HEAD TO N. BRIDLINGTON: CHALK
- (soft but resistant with horizontal bedding plains, leads to joints)
- cracks, caves, arches, stacks, stumps on wave-cut platform formed by abrasion by shingle from cliff recession
BRIDLINGTON TO SPURN HEAD: BOULDER CLAY
- unconsolidated glacial till from 20,000 years ago (last ice age)
- rate of erosion: +1.7m a year (Great Cowden: 10m a year)
- 5km lost in 2,000 years
- Slumping
- Sandy beaches (e.g. Bridlington)
- Zone of erosion and sediment transfer
- 7m tidal range
SPURN HEAD: SAND
- 5km long
- Deposited sand to form recurved spit
- Sand dunes on spit
- Salt marsh and mudflats on landward side
Why does the Holderness Coast erode rapidly?
think in terms of marine inputs
- MARINE INPUTS
- marine inputs create large waves and high levels of erosion
FETCH, WINDS AND WAVES:
- Fetch from NE is 500-800km (Norway) - not large
- Warm Atlantic ocean currents that circulate around North Sea add energy and increased frequency of destructive waves
- Depressions and winter storms cause storm surges due to strong winds (short term rise in sea level and high tide), draws sediment offshore (made worse if prevailing NW winds are blowing)
- North Atlantic drift
SMALL, ENCLOSED SEA:
- small, enclosed sea creates large waves
- deep offshore zone, little friction to absorb wave energy
- eustatic sea level rise (very slow)
Why does the Holderness Coast erode rapidly?
List the 5 reasons
- GEOLOGY
- MARINE INPUTS
- LONGSHORE DRIFT AND BEACHES
- SUB AERIAL PROCESSES
- HUMAN FACTORS
Why does the Holderness Coast erode rapidly?
think in terms of longshore drift and beaches
- LONGSHORE DRIFT AND BEACHES
- longshore drift moves south
- narrow beaches because clay breaks down into small particles, which are then transported offshore by suspension
- destructive waves result in little deposition, so narrow beaches lower in height which results in less cliff protection
- high tides, storm surges and spring tides attack coast due to narrow beaches
- when ocean current meets the outflow the river humber, the flow is turbulent and sediment is deposited
Why does the Holderness Coast erode rapidly?
think in terms of subaerial processes
- SUBAERIAL PROCESSES:
- chemical weathering only happens in chalk (carbonation)
- biological & mechanical weathering happens (wetting and drying)
- seawater attacks base of cliff
- climate -> rainwater saturates boulder clay
- all 3 produce in rotational slumping
- slumped material at base of cliff removed offshore in suspension
- chalk = rock falls
Why does the Holderness Coast erode rapidly?
think in terms of human factors
- HUMAN FACTORS:
- Groynes: create a steeper (due to sediment accumulating), wider beach BUT after it: lower, narrow and flatter beach (terminal groyne syndrome) due to sediment starvation
- Impact of sea level change:
- very slow eustatic sea level rise
- increased erosion along cliff coastline and flooding in low lying parts
- impact felt at Spurn Head as low lying and will overtime shrink and be overtopped as the sea level rises
- increased erosion and less deposition
Who are the key players and stakeholders in the Holderness Coast SMP?
- National government and DEFRA - since 2010, they have cut budget (very powerful as they fund)
- Local government and Environment Agency - East Riding Council’s role to manage the coast (powerful)
- Stakeholders (farmers, residents, tourist industry) - impacted can have a say but no power
- Environmental stakeholders - RSPB (birds) and English Nature want to protect breeding grounds at Spurn Head so need natural processes to continue (very powerful)
- Insurance companies - will not insure people with no coastal protection (risk is too high), so no compensation for people who lose land
Why is the Holderness Coast not receiving much funding for coastal protection?
80-90% of Holderness Coast is farmland (low value land), the reasons are not enough for funding
What is the overview of the coastal protection?
- Public defences in Bridlington, Hornsea, Mappleton, Withernsea and around the gas terminal at Easington
- Private defences at caravan parks in Skipsea (temporary planning permission)
- 11.4km of 61km has coastal protection, mixed with 19th century structures
- No recent schemes of coastal protection
What are the coastal protection policies in place for Bridlington?
BRIDLINGTON:
- population: 25,000 + tourists
- 4.7km of high masonry and concrete sea walls
- timber groynes to stabilise beach
What are the coastal protection policies in place for Skipsea?
SKIPSEA:
- population: 780
- gabions (built by local landowner to protect caravan park)
- rollback of caravan parks encourages, no closer than 400m to cliff edge
- managed retreat
What are the coastal protection policies in place for Hornsea?
HORNSEA:
- population: 8,800 + tourists
- 1.86km of concrete sea walls, recent increase in height and added wave profile
- rip rap in front of wall
- groynes (recent strengthening)
- beach nourishment
- steel doors to guard entrance to beach
- sand dunes to the south planted with trees
What are the coastal protection policies in place for Mappleton?
MAPPLETON:
- population: 400 + tourists
- 2 rock groynes
- rock revetment, 500m in length (granite from Norway)
- cliff regrading (by 2002 - slumping issues)
- beach nourishment
- cost in 1991: £2 million
What are the coastal protection policies in place for Aldborough?
ALDBOROUGH:
- no management, cliffs are rapidly eroding
- rollback of caravan parks encouraged
