Coastal Landscapes and Change Flashcards
What is hydraulic action in wave erosion?
Wave pressure compresses air in cracks.
How does abrasion contribute to wave erosion?
Waves carry sediment that scrapes rocks.
How does corrosion affect cliff erosion?
Sea water dissolves soluble rock materials.
How does rock strength affect erosion rates?
Stronger rocks erode slower, weaker faster.
How does wave erosion affect boulder clay?
Soft boulder clay erodes quickly, leading to retreat.
How does jointing affect wave erosion?
Joints increase surface area, accelerating erosion.
How does weathering contribute to coastal recession?
Weathering weakens rocks, increasing erosion rates.
What mass movement processes affect coastlines?
Rotational slumping destabilizes cliffs, enhancing erosion.
How does weathering affect cliff erosion?
Weathering breaks down rock material, accelerating erosion.
How does lithology affect coastal erosion?
Hard rocks erode slower, soft rocks faster.
How does rock structure influence erosion rates?
Jointing and bedding planes increase erosion.
How does rock structure affect coastal features?
Resistant rock forms steep cliffs, softer forms gentle slopes.
What conditions create coastal deposition landforms?
Low-energy environments with sediment accumulation form landforms.
How does longshore drift affect deposition?
Longshore drift moves sediment, creating beaches and spits.
How does wind contribute to coastal deposition?
Wind blows sand inland, forming dunes.
How does vegetation stabilize coastal dunes?
Pioneer species like marram grass bind sand.
How do dunes form over time?
Vegetation succession gradually builds dunes above tide.
How do sea walls and groynes protect coasts?
Sea walls absorb wave energy, groynes trap sediment.
What is the goal of hard engineering?
To prevent coastal erosion and protect land.
How does No Active Intervention manage coastal recession?
No intervention allows natural processes to dominate.
How does strategic realignment manage coastal recession?
It involves relocating structures to safer locations.
What is Terminal Groyne Syndrome’s impact?
Increased erosion occurs down-drift of groynes.
How does post-glacial rebound affect sea level?
Post-glacial rebound causes local sea level fall.
How does subsidence and uplift affect coastlines?
Subsidence lowers sea levels, uplift raises them.
How does isostatic uplift affect Scotland’s coastline?
Scotland experiences sea level fall due to uplift.
How does global warming affect sea levels?
Global warming causes thermal expansion, ice melt.
How does thermal expansion affect sea levels?
Thermal expansion of oceans increases sea levels.
How does ice melt contribute to sea level rise?
Melting ice sheets add water to oceans.
How do hard and soft engineering differ in Cromer and Trimingham?
Cromer uses hard engineering, Trimingham soft engineering.
Which is more effective in managing coastal recession?
Hard engineering is more effective than soft engineering.
How are wave-cut platforms and notches formed?
Wave erosion creates platforms and notches.
How does deposition reduce coastal recession?
Deposition reduces wave impact, lowering erosion.
How are spits formed?
Longshore drift moves sediment, forming spits.
What are emergent landforms caused by sea level change?
Raised beaches and fossil cliffs form.
What are submergent landforms caused by sea level change?
Rias, fjords, and Dalmatian coastlines form.
How do beach characteristics differ in winter vs. summer?
Winter: steeper, larger sediment; summer: flatter.
How do marine processes affect sediment transport?
Longshore drift moves sediment along coasts.
How do subaerial processes affect cliff development?
Weathering and mass movement create cliff features.
How do erosional processes contribute to sediment production?
Erosion breaks rocks, contributing sediment to system.
How has global warming affected sea levels since 1920?
Sea levels have risen approximately 200mm.
What is the daily gas processing capacity at Easington Gas Terminal?
Processes 1 million m³ gas daily.
What was the cost of the managed realignment scheme at Medmerry, West Sussex?
£28 million for 183 hectares habitat.
How many homes are protected by dune regeneration at East Head, West Sussex?
Protects over 100 homes from erosion.
How much of the Undercliff road on the Isle of Wight is closed due to landslides?
1.2 km of road closed due to landslides.
How high are the raised beaches at Ullapool, Scotland, above sea level?
Raised 10–15 metres above sea level.
How far inland does the River Dart ria extend?
River Dart ria stretches 10 km inland.
How deep is the Sognefjord in Norway?
Sognefjord reaches depths of 1,300 metres.
How many islands make up the Dalmatian Coast in Croatia?
Over 1,200 islands in the Dalmatian coast.
What is the height of the cliffs on the south coast of Madeira?
Madeira’s cliffs reach 580 metres tall.
How fast does the Holderness Coast erode annually?
Erodes at 2 metres per year.
What is the sediment cell concept?
Coastlines divided into self-contained units.
What processes occur in sediment cells?
Erosion, transportation, and deposition of sediment.
Are sediment cells truly closed systems?
No, some sediment exchange occurs.
What causes sediment exchange between cells?
Tidal currents and wind direction.
What are sub-cells in coastal systems?
Smaller divisions within sediment cells.
What does sediment transport influence?
Coastal landform formation, like beaches.
How do beaches form?
Accumulation and reworking of sediment.
What are berms, cusps, and runnels?
Features formed by wave action on beaches.
What is longshore drift?
Sediment movement along the coastline.
What features does longshore drift create?
Spits, bars, tombolos, and more.
What causes spits to recurved?
Changes in wind direction or tidal influence.
How do double spits form?
Sediment transported in opposite directions.
What is a cuspate foreland?
Landform formed by opposite sediment transport.
What is an example of barrier islands?
Islands formed offshore, like in the US.
What role does aeolian transport play in landform creation?
Wind-driven transport forms coastal features.
What factors influence coastal management?
Risk, economic value, environment, stakeholders.
What is the physical risk in coastal management?
Erosion and flooding of coastal areas.
What is the economic value in coastal management?
Land and infrastructure’s monetary worth.
How are high-value areas managed?
Hold the line policies protect them.
What is hold the line?
Protection of key coastal infrastructure.
What is left to natural processes in coastal management?
Lower-value farmland or land areas.
What is the role of environmental considerations?
Protect areas like SSSIs and reserves.
What are softer engineering solutions?
Natural methods like beach nourishment.
What is strategic realignment?
Allowing coastal retreat to adapt.
What is the Thames Barrier?
Engineering solution protecting central London.
What can cause local conflicts in coastal management?
Uneven benefits between areas.
What happened at Medmerry?
Wetland creation displaced farmland, causing disputes.
What happened at the Isle of Wight?
Non-intervention led to road closures.
What is an example of successful collaborative management?
East Head: dune regeneration benefits both environment and tourism.
How does vegetation help stabilise coastlines?
Plants trap sediment, reducing erosion.
What is dune succession?
Plant growth stabilises dunes over time.
What are examples of pioneer species?
Sea twitch and lyme grass.
What stabilises mature dunes?
Marram grass grows on mature dunes.
What role do halophytes play?
They trap sediment in estuaries and marshes.
What are salt marshes?
Coastal wetlands formed by halophytes.
What role do mangroves play?
Stabilise coastlines in tropical regions.
How does human activity affect vegetation?
Planting and protecting vegetation aids stability.
How does sea level change affect coastlines?
It creates emergent or submergent coastlines.
What is an emergent coastline?
Formed by rising land or falling sea levels.
What are raised beaches?
Elevated beaches formed by emergent coastlines.
What are submergent coastlines?
Formed by rising sea levels flooding land.
What are rias?
Drowned river valleys, like River Dart.
What are fjords?
Submerged glacial valleys, deep and steep.
What is a Dalmatian coast?
Submerged mountain ranges forming islands.
How does geology affect cliff formation?
Different rock types create varied cliff shapes.
How do igneous and metamorphic rocks affect cliffs?
Produce steep, tall cliffs (e.g., basalt).
How do unconsolidated materials affect cliffs?
Produce low, rapidly eroding cliffs (e.g., boulder clay).
What geological features affect cliff shape?
Faults, folds, and rock dip.
How do faults influence cliffs?
Create abrupt cliffs, like Tintagel.
How does rock dip affect cliffs?
Creates sloping profiles, like Lulworth Cove.
How does jointing influence cliffs?
Forms vertical cliffs, like Drumadoon Sill.
What is differential erosion?
Erosion of alternating rock layers, creating varied cliff shapes.
What is hard engineering?
Expensive solutions altering coastal systems.
What are examples of hard engineering?
Groynes, sea walls, rip rap.
What is soft engineering?
Sustainable, lower-cost, natural process methods.
What are examples of soft engineering?
Beach nourishment, dune stabilization, re-grading.
What is Integrated Coastal Zone Management (ICZM)?
Coastal management within littoral cells.
What factors affect coastal management policies?
Engineering feasibility, geology, land value.
What tools guide policy decisions?
Cost Benefit Analysis, Environmental Impact Assessments.
What is the Thames Barrier?
Protects London, £534 million cost.
Why is the North Norfolk coast unprotected?
Low land value and vulnerability.
What is Medmerry, Selsey’s strategy?
Strategic realignment, £28 million cost.
Why is ‘No Active Intervention’ used?
Geological challenges, high costs.
Why is East Head prioritized?
Environmental sensitivity over economic factors.
What national priorities influence policies?
Infrastructure protection, coastal access.
What is the effect of global warming on coastlines?
Rising sea levels, more intense storms.
How do local factors worsen coastal risk?
Elevation, subsidence, vegetation removal.
How is coastal recession accelerated?
Geological, marine factors, human activities.
What causes storm surges?
Rising sea levels, climate change.
What is the rate of sea-level rise in the Pacific Islands?
3–5 mm per year sinking.
How does global warming affect tropical storms?
Increases frequency, intensity, stronger winds.
What’s the effect of increased precipitation?
Stronger subaerial processes, faster erosion.
What is isostatic downwarping?
Land sinking increases flood risks.
What’s the impact of human actions on the Maldives?
Removal of mangroves increases vulnerability.
How much erosion occurs in Holderness?
Up to 2 meters per year.
What are the consequences of coastal recession?
Loss of housing, businesses, infrastructure.
How does hard engineering affect coastal systems?
Provides protection but alters systems.
What is soft engineering’s advantage?
Works with natural processes sustainably.
What is the purpose of sustainable management?
Address future threats, rising sea levels.
How much did the Thames Barrier cost?
£534 million, prevents £5 billion damage.
What happened at Blackwater Estuary?
Hard defences abandoned, returned to nature.
How much erosion occurs in Mappleton?
2 meters per year.
How much did Medmerry’s realignment cost?
£28 million for sustainable management.
How does the Isle of Wight manage erosion?
Soft engineering, vegetation planting.
Why is hard engineering impractical in the Maldives?
High costs, limited resources for defenses.
What is the conclusion about coastal protection?
Hard engineering offers protection but costs.
