Lesson 14- Holderness Coasts Case Study Flashcards
What factors influence the energy within the Holderness Coastline?
- Fetch
- Coriolis Force
- Storms
- Air masses
- Tides
Energy inputs into Holderness-Fetch
- Fetch helps generate large waves - enables destructive waves to be created by prevailing north easterly winds across the North Sea.
Energy inputs into the Holderness-Coriolis Force
- Coriolis Force due to the earths rotation directs waves at the coastline from the north east.
-This force can result in successive days of powerful destructive waves along the coastline which can remove metres of land at a time.
Energy inputs into the Holderness-Storms
- Storm conditions within the North Sea, particularly during the winter months create destructive waves and high energy.
Energy inputs into the Holderness-Air Masses
- Arctic maritime air pushes towards the UK, creates bigger storm waves (4m in height) , which erode the coastline due to high energy.
Energy inputs into the Holderness-Tides
- Large tidal range up to 7 metres
-Scouring and abrasion the base of cliffs and sea bed causes cliff retreat of, on average 1.5m a year.
What human factors affect the coastline?
- ICZM/SMP’s
- Hard/Soft engineering
- Climate change
Factors contributing to a fast eroding coastline?
- Weather/Seasons
- Waves
- Geology
Factors causing fast erodion at holderness-Weather/Seasons
- Winter strorms mean stronger waves
- Rain excacerbates mass movement
- Saturated clay cliffs suffer increased runoff leading to slumping
Factors causing fast erodion at holderness-Waves
Waves come from the north east which is the direction of the largest fetch
-Destructive waves erode foot of the cliffs and longshore drift carries sediment southward
Factors causing fast erodion at holderness-Geology
- Two main types found here are chalk and boulder clay casuses diffreing erosion rates
-Flamborough head consists of wave cut platforms, caves archs stacks and stumps
-Briddlington has boulder clay with steep cliffs
What processes occur at the Holderness?
- Weathering
- Erosional
- Transportation
- Depositional
Weathering at Hornsea
- Speeds up erosional landform formation
-causes disintegtarion of rocks in situ - Causes mass movement and makes cliffs collapse as boulder clay is more prone to slumping
Erosion at Hornsea
- Creates the landforms for deposition at Flamborough head- wave-cut platforms
-3% of sediment deposited at Spurn Point
Transportation at Hornsea
- These transportation prcesses like longshore drift supply sediment for depositional landforms
-Spurn Point Spit
Depostional processes at Hornsea
- Creates mudlats and spits due to how ocean currents meet the Humber River depositing sediement.
- Creating beaches for tourism, hornsea and bridlington rely on this process for economy
Positive impact of humans on deposition
- Humans have installed groynes at Hornsea, this has stopped sediment being transported by longshore drift building up beaches
- SMP in place protect by dispositional landforms and ensures protection under 2100 at the earliest
Negative impact of humans on deposition
- Groynes have had a negative impact (terminal groyne syndrome) further down the coast by starving the beach with sediment.
-Beaches Spurn Point Spit - Climate is casusing increased sea levels and more effective waves causing more erosion of Spurn Point
Why does the Holderness need managing?
- Fastest eroding coastline in europe at 2cm per year
- Made of soft boulder clay and chalk
- Longshore drift is the dominant process
- Narrow beaches here which reduces protection
Why is the whole of the holderness not protected?
- Only 2300km of the 17,000km coastline is here
- More than 200 houses are at risk of being lost to coastal erosion in the next 20 years
What are the 4 managing options?
- Hold the line
- Advance the line
- Managed realignment
- Do nothing
What is the SMP?
- Shoreline management plan is written about each sediment cell
-based on priciples of sediment cells
-Hold The Line at Withernsea
-No Active Intervention between Hollym & Dimilington
-Hold The Line at Easington
-Managed Retreat from Kilnsea to Spurn Point
What is the ICZM?
- Where sections of the coast are managed together
-they recognise that sediment cells interact with each other and that changes in one area of the coast impact another
How is Hornsea managed?
- Hornsea-sea wall+groynes=5.2 mil
- Withernsea-groynes,recurved sea wall, beach nourishment=6.3 mil
- Spurn Point-No intervention
- Humber estuary-managed retreat as 500,000 people risk of flooding due to being 2m under sea level
How will climate change impact Holderness?
- Increased erosion rates at Holderness
- Increased sea levels-flood risk
- More extreme weather-low pressure systems create destructive waves
- Salty water-Salination of water in Humber Estuary
- Erosion of depositional landfroms (beaches)
