The Coastal Environment AQA B Geography Revision Guide

Case Study: How is the Coast an example of a multi-use area? Definition: A multi use area is a part of the coastline which offers a range of social, economic and environmental activities. Head – stunning scenery and birds attracts tourists to visit. – provides retirement homes with sea side views. Hull – Every year, 13 million tonnes of imported cargo pass through the port which employs 5000 people. Fishing industry lands fish at Hull docks. Holderness Country Park – provides tourists with a large fishing lake and a dog walking area. Guests can stay in either log cabins or caravans. Easington Gas Terminal – provides 1000 jobs and 25% of UKs gas supply. Humber Estuary: off-shore & on-shore wind turbines use strong winds to generate renewable electricity. Case Study: Why has the Holderness Coastline developed?

Human Activities Economic Activities

• Improved Transport • Improved Transport and • Rising living standards Communication • Range of jobs (e.g. Easington for • Available space (e.g. Hull for industry, Bridlington for tourism). development of industry and • Tourism (scenery and wildlife) (e.g housing) Flamborough Head and Head) • Large workforce (e.g. Hull which • Attractive place to live (e.g. employs 5000 people in its dockland) Bridlington – views of the sea) • Natural Resources (e.g. fish in Hull, • Second homes/retirement (e.g. gas in piped to Easington) Bridlington) • Tourism (e.g. Hornsea, Bridlington, Various caravan and camping sites along the coastline) How is development impacting the environment?

Diesel/oil spillage Industrial units and Some animals and from the tankers may factories have polluted the birds have choked affect marine life; sea causing death of on litter on beaches noise from tankers aquatic life and thus from tourists. disrupting food chains.

Conflicts of Interest : Coral reefs (e.g. St Lucia) Different coastal users who are being damaged from make problems for each How is development tourists collecting souvenirs other. along the coast and anchors from fishing damaging the local vessels. •Oil refineries of S. Humber environment? pollute water for local fishermen. Footpath erosion at Flamborough Head due •Ships coming up R. Humber to high tourist numbers. cause danger for tourist wind-surfers & jet skiers Sea defences along the Holderness •Wind turbines at Easington Cliff top developments Coastline have stopped the can kill migrating birds using have made the cliffs movement of sediment to Spurn Spurn for migration. unstable which has Head, an important habitat for increased rates of erosion. numerous rare birds .

Case Study: How is the Holderness Coastline protected?

Protection Scheme How does it protect the coastline?

Heritage Coast at -Encourages the use of public transport which reduces cars, congestion, noise and Flamborough Head air pollution - farmers receive extra money through grants if they farm in a way that protects the environment and wildlife biodiversity (range of species) - footpath erosion is reduced by encouraging people to stay on paths through signage Wildlife -Organises seasonal beach cleans at two locations. All rubbish is separated out and Trust at Spurn and recycled where possible which promotes sustainability -Helps to prevent millions of marine animals, birds, turtles and fish dying each year Flamborough Head as a result of entanglement or eating litter floating around in the sea or beach. -Keeps beaches tidy which encourages tourists back into the area.

Greenbelts around -they have prevented new houses and industries from being built land ideal for Bridlington and farming land. -fewer development on cliff-faces has reduced the pressure on cliffs making them Hull more resistant to erosion and weathering. -stopped woodlands and hedges being removed allowing for ecosystems to continue to flourish.

Marine -The MCS has helped reduced overfishing to protect fish stock numbers from Conservation Sites further declining. In the future, it is hoped that fish populations will increase. -The MCS also prevents sand dredging of the sea bed which can damage nesting (MCS) sites of many fish. What are the differences between constructive and destructive waves?

What determines the strength of a wave? - Strength of the wind Swash is the Backwash in - How long the wind has been blowing movement of the movement - The distance between the ocean the wave has water up the of water down a crossed (fetch) beach beach

Constructive Waves Destructive Waves Strong Swash, Weak Backwash Weak Swash, Strong Backwash

Deposits rather than erode Erodes rather than deposits

Low wave height (less than 1 metre) High wave height (more than 1 metre)

Low wave frequency High wave frequency.

What are the types of erosion and weathering?

Key Terms: Erosion – the wearing away of rocks by the action of the sea and their removal Weathering – the breaking up of rocks in situ by the action of the weather, chemicals and biology. Erosion Weathering

Attrition Wetting/drying Energy from breaking waves causes rocks and Constant wetting and drying causes rocks to pebbles to smash into each other They expand and contract, resulting in surface eventually break down into smaller and cracks and weakening of the rock. rounder pieces Freeze thaw Weathering Abrasion Water gets into cracks in rocks and expands Materials, like boulders, pebbles and sand are as it freezes, putting pressure on the hurled against the cliff by breaking waves. surrounding rock. This causes undercutting and the breaking up Corrosion of rocks. Carbon Dioxide dissolves in rainwater, producing acid rain. This reacts with Hydraulic Action minerals inside certain rocks (e.g. Water is thrown into cracks within the cliff limestone), causing them to be weakened by breaking waves. Air inside the cracks is and easily dissolved. squashed by the water and the pressure inside increases When the wave sinks back, the pressurised air expands explosively. This causes the rocks to shatter so the cracks slowly become bigger and deeper. Erosion on Hard Coastlines How are headlands and bays formed?

1) Hard (e.g. chalk) 4) As the headland and soft rock (e.g. juts out to sea, it boulder clay) are receives the full at right angles to force of the waves the coastline. energy. This allows 2) Soft rock is eroded the headland to be at a faster rate by eroded slowly over hydraulic action and time. abrasion. 3) Over time, a bay is formed within the soft rock. The shape of the coastline reduces the energy forming constructive waves. This allows beaches to form. How are cave, arches and stacks formed? Headland

4) Overtime, the base of the stack is eroded by abrasion which then topples over in a storm to form a stump.

1) A cave is formed 2) An arch is formed 3)A stack is formed when the roof of when hydraulic when hydraulic action the arch is weathered by freeze thaw action widens the and abrasion continue to action. This weakens it causing to joints in the rock erode the backwall of a collapse as a rock fall due to gravity. over time. cave all the way through the headland. How are wave cut notches and platforms formed?

2) The top of the cliff is 4) Cliff collapses due to gravity weakened by freeze as a rockfall. thaw weathering.

5) The cliff slowly retreats back 1) Erosion from the leaving a wave cut platform sea (i.e. abrasion behind. and hydraulic action) start to undercut the cliff base. 3) This wave cut notch increases in size until the weight of the cliff . can no longer be supported. Erosion on Hard Coastlines How do rockfalls happen?

Process: Freeze thaw weathering is when water enters cracks between rocks and freezes. This causes the water to expand which puts pressure on the surrounding rocks. Over time, it weakens the rock causing it to break up. This causes rock to fall from the cliff face due to gravity as a rockfall.

Landforms A scree slope of fallen rock is formed at the bottom of the cliff face.

Erosion on Soft Coastlines

Process: SLUMPING Slumping is a rapid movement of boulder clay that occurs on a curved slip plane.

It happens when water percolates (soaks into) into the boulder clay until it becomes saturated with water making it heavy. The weight of the cliff above it forces the rock down towards the sea as a mud flow.

Landforms: A step like cliff face is present after the slumping has occurred. Vegetation (originally from the cliff top) will also be present in patches on the cliff face.

LANDSLIDES AND MUDFLOWS Process: A landslide is a rapid movement of boulder clay that occurs on a slip plane that is parallel to the cliff face.

It happens when erosion from the sea undercuts the base of the cliff. This destabilises the cliff face causing the clay to slide down the cliff as a landslide.

Landforms: An accumulation of sediment remains at the base of the cliff which is known as a scree slope. Deposition: How are beaches formed?

Swash Aligned Beach Drift Aligned Beaches (longshore drift) Waves approach the coastline and then break in 3)Backwash moves the 4) Material is picked up parallel to the coastline material straight back again and moved back up down the beach to the the beach as swash. Swash and backwash sea. 6)The sediment move sediment up and 2) Swash moves in a zig-zag down the beach. moves the motion along the material up beach. Over time, Creates an even profile the beach at large amounts of along the shoreline an angle. sediment are moved along the beach. During storms, berms 1) Prevailing wind 5) Backwash brings the (ridges of sediment can direction moves waves material back down the form). onshore at an angle. beach again.

Deposition: How are spits and bars formed?

e.g. Spurn Head, e.g. Slapton Ley, Holderness Coastline Devon

How is a spit formed? How is a bar formed? 1. Waves carrying material are blown in the 1. Waves carrying material are blown in the direction of the prevailing wind. direction of the prevailing wind. 2. Longshore drift moves material along the 2. Longshore drift moves material along the coast. coast. 3. Where the coastline changes direction, 3. Where the coastline changes direction, material is deposited in water sheltered by material is deposited in water sheltered by the headland. the headland. 4. The material builds upwards and outwards 4. The material builds upwards and outwards to form a spit. to form a spit. 5. A mud flat starts to develop in the 5. The spit continues to grow across the bay sheltered water behind the spit due to less area and joins to the headland to form a erosion. bar. 6. Secondary winds can cause the end of the 6. A lagoon is formed behind the bar. Over spit to curve forming a hooked end time, this is filled up with sediment to form 7. The salt marsh develops on the mud flat in land. the sheltered water. Coastal Management Why do some areas of the coast need protecting but not others?

There are 4 Management Options for Not all coastlines can be protected as this would be each section of coastline: highly expensive. Do nothing (let the coast erode naturally) There a variety of socio-economic reasons why seaside towns need to be protected. This includes where large Hold the line (defend the coastline to numbers of people live and local businesses.(e.g. keep the coastline where it is at present) Bridlington).The Easington Gas Terminal also needs Advance the Line (build defences protecting because it is so important in providing gas further out from the existing coastline to for the UK whilst also providing jobs. help reclaim lost land) The whole of the Holderness coast is vulnerable to Managed realignment (develop erosion as it is made of soft rock. This means decisions defences further inland and permit some are made about which bits to hold the line and which coastal flooding) areas will have to be allowed to erode back.

Shoreline Management Plan The aim of the Shoreline Management Plan is to identify which areas of coast require protection, and which don’t. By looking at the coast as a whole, planners can make sure that any changes to one part of the coast will not impact another part of the coastline. Pevensey Bay: An example of Soft Engineering Definition: Working with the natural processes of sea and sand in a more environmentally sustainable way. Using the natural processes to bring about an intended effect.

Name & Picture How does it reduce Advantages Disadvantages erosion?

Beach Recycling As sediment moves due to • Adds to tourist • Needs frequent longshore drift, some parts of the amenity by renewal of more beach lose sediment whilst others making bigger sand gain sediment. To even this out, beach • Does not material is moved back to the • Attractive – no protect cliff areas where sediment has been unsightly face against the lost. This is carried out after structures like energetic and winter storms. hard engineering destructive • Works with the winter storm Beach Dredgers are used to take sand natural waves. Replenishment from the sea bed which is then processes of the • Local people sprayed onto the beach. This coast therefore have the opinion replaces lost beach material from more that soft longshore drift and produces a environmentally engineering is large beach. This causes more friendly not as good as friction and reduces erosion. hard engineering.

Beach Reprofiling This involves using bulldozers to push sediment up the beach. This changes the slope angle of beach from steep to gentle. This allows for more wave energy to be absorbed reducing erosion. Sometimes plants are placed at the back of the beach to soak up wave energy. Holderness Coast: An example of Hard Engineering Definition: Controlled disruption of natural processes (e.g. erosion and longshore drift) by using man-made structures. Name & Picture How does it Advantage Disadvantages reduce erosion?

Sea Wall (e.g. Curved sea walls Protects the base of Can be expensive to Hornsea) reflect the energy of cliffs, land and maintain as sea-walls the waves back to the buildings against are eroded over time. sea preventing erosion erosion. Can prevent of the cliff. coastal flooding in some areas.

Rock Armour (e.g Absorb wave energy Cheaper than sea Unsitely and reduces Hornsea) reducing the erosion walls. access to beach. Can of the cliff face. be expensive to obtain and transport the boulders.

Gabion (e.g. Absorb wave energy Easily installed and Not very attractive, Hornsea) reducing the erosion cheaper than sea walls. needs frequent of the cliff face. checking & repair, not easy for people to get over to get to beach, may contain rats nests

Groyne (e.g. Reduces the rate of Allows a large beach Can be seen as Hornsea) longshore drift to form encouraging unattractive. Costly to allowing a large beach tourism. build and maintain to develop. The because causes friction with waves reducing wave energy thus causing less erosion Cliff Drainage Pipes and drains are Can be used on soft Can cause erosion (Mappleton) put into the cliff to rocks effectively. where water leaves remove water that the pipe into the sea. causes slumping. Can affect local wildlife

Tetrapods (Japan) Absorb wave energy Can be built on site. Isn’t completed reducing the erosion Reduces transport effecting at reducing of the cliff face. costs. erosion as some wave energy is not absorbed. How can we protect the coast from sea level rise? Managed realignment Case Study: Wallasea Island, Essex

What is managed realignment?

Managed realignment involves the construction of new sea wall at a location behind existing sea wall. This allows the area between the old and new sea wall to become flooded forming a saltmarsh. The created saltmarsh helps reduce erosion and protects against sea-level rise.

Case Study of managed realignment: Wallasea Wetlands, Essex, UK

What has happened? With the coastal defences in the north of the island crumbling away, the government decided to realign (change the shape of) the northern part of the island by constructing a new embankment (wall) inland (further south) and allow the sea to further break through (breach) the old sea defences.

How has it worked? The formed salt marsh provides a natural defence against flood tides and will be increasingly important as sea levels rise. Sea water is able to spread out over the salt marsh reducing the risk of flooding further inland. Reduced erosion will also take place as plants absorb wave energy.

Has it been successful? Benefits:  It meant that they saved money that would have Farmland wasn’t lost in the creation of the otherwise been uselessly spent on replacing the current salt marsh. sea defenses i.e. a new sea wall that would have cost Few buildings were destroyed. around £1,000,000 per kilometre.. Fisheries were improved Created 115 ha of saltmarsh for birds. Case Study: How can we make the Holderness Coastline sustainable?

What are the current pressures along the Holderness coastline? • Farming related pollution • Overfishing • Footpath erosion • Alternative sources of energy • Overpopulation • Tourism What is the ICZM and what are the aims? • ICZM stands for Integrated Coastal Zone Management. It is a 100 page document informing planners on how to be sustainable along the coastline. • Aims to reduce the pressures along the Holderness Coastline by encouraging sustainable practices. Sustainability: Meeting the needs of the people today without causing problems for future peoples.

How is the ICZM along the Holderness Coast sustainable? ICZM Environmental Social Economic Element sustainability Sustainability Sustainability

To encourage appropriate Reduces amount of fossil Reduces energy prices as less Provides jobs during the offshore wind / fuels burnt which release money has to be paid on manufacture and maintenance wave power greenhouse gases. This will importing fossil fuels. It makes of offshore wind and wave generation help reduce the threat of energy affordable for low energy plants. global warming. income people. To support schemes that have Farmers use less chemicals Food grown organically has a Environmentally friendly environmentally such as fertilizer and higher nutritional value due to techniques cost less to friendly farming pesticides which cause higher vitamin and mineral implement so farmers see techniques water pollution. This helps content. People become larger profits which can help keeps coastal waters clean. healthier. compensate loss of land through erosion. To ensure the continued Fish stocks remain high for Provides people with a Provides fishermen with long viability of the all species allowing for sustainable supply of different term job security as fish stocks inshore fishing biodiversity and varieties of fish at low prices. are being sustained. industry maintenance of existing Provides a balanced diet. food webs. To provide on-site information and Prevents footpath erosion Local visitors centre to education and trampling of plants. Bird educate people about the Profits made through tourism materials to species do not get disturbed wildlife at various coastal can be used to further educate and by visiting tourists locations and how to protect it conservation work in coastal inform both areas. visitors and local people.