November mocks key facts

Case studies:

Changing Landscapes - coasts

• Sediment cell – South Downs sediment cell

  • Sub-cell 4d along the Sussex coast

  • Between Selsey Bill and Beachy Head

  • Defended with rock reefs, wooden and rock groynes

  • Pebble beaches

  • Dominant drift direction west to east

  • Up to 5000m³ gravel and sand lost round Beachy Head

  • Dredging of Shoreham Harbour, Brighton Marina, Newhaven Harbour

• Build-up and removal of a beach (system feedback) – Crantock Beach, Cornwall

  • Northwest facing beach in Northern Cornwall

  • River Gannel flows on the northern edge of the beach

  • Ever-changing environment

  • Employs a shoreline management plan

  • Has experienced excessive erosion in recent years (since 2013), especially after the 2013-2014 storms

  • Erosion of up to 3m in depth

  • Mobile zone is degrading, whilst the beach zone is more stable

• Coast working as a system – Aquitaine Coast

  • Located in the southwest of France

  • Complete shore system composed of beach, dunes and pine tree forest

  • Sandy beaches and dunes

  • Employing hold the line/limited intervention

  • Sea wall, groynes, beach nourishment, dune restoration

  • Stores of the cap ferret spit, arachon estuary, dune du pilat and araguin offshore bar

  • Outputs of the ocean and longshore drift

• Microtidal range – Eastern Australia

  • Found in parts of New South Wales and Queensland

  • Wave action plays a larger role in Charing the coast than tidal energy

  • Example is Yalimbah Creek

• Macrotidal range – most of the UK coast

  • Key regions include Bristol Channel and Severn Estuary (up to 15m)

  • Strong tidal currents and dynamic sediment movement

  • Other examples include Humber and Mersey estuaries

  • Drive rapid sediment transport, leading to extensive tidal flats, formation of tidal deltas, and notable erosion/deposition patterns

• 1.1.3 High and low energy environment – Gower Peninsula

  • Mixed energy coastal environment with high and low energy areas

  • High energy areas- Rhossili bay- experiences strong winds and waves, making it popular for surfing

  • Low energy area- Oxwich bay- large, sheltered bay with extensive dunes and salt marshes

• 1.1.5 Headland and Bay – Swanage Bay and Studland Point, Dorset

  • When bands of softer rock on a discordant coastline is eroded faster than the bands of harder rocks, creating areas of lad that stick out form the mainland

  • Has alternating bands of limestone/chalk and clays/sands

  • Ballard point- made of chalk

  • Durlston head- made of limestone

  • Located in Dorset

• Stacks and stumps – Old Harry and Old Harry’s wife, Dorset

  • The erosion of a cave into an arch, that then collapses to form a stack

  • The stack then gets eroded into a stump

  • Old harry is a stack and his wife is a stump, near Ballard point

  • Made of chalk, which is resistant enough for a cave-arch-stack sequence

• Cove – Lulworth Cove

  • On the Dorset coast, next to the village of Lulworth

  • Bedrock surrounding the cove is sedimentary, and so was easily erodes

  • Entrance is a breach in the very resistant Portland stone

• Blowhole – Nakalele Point, Hawaii

  • Northernmost point on the island of Maui

  • Water released by the blowhole can reach up to 100 feet in the air

  • Rock in the area is jet black lava rock

• Soft rock cliff – Highcliff, Barton-on-Sea (boulder clay rock)

• Hard rock cliff – Cornish Coastline (basalt rock)

• 1.1.6. Bar – Chesil Beach

  • Spits that extend across two sides of a headland, forming a lagoon behind it

  • Located in Dorset

  • Behind the spit there is The Fleet, which is a lagoon

• Cuspate foreland – Dungeness foreland, Kent

  • Triangular shaped projections that form from longshore drift moving in two different directions

  • Located in Kent

  • Formed over the last 5000 years

  • Comprised largely of gravel

  • Attracts 1 million tourists annually

• Spit – Orford Ness

  • Linear deposits of sand and shingle that is attached to land on one end

  • Formed by longshore drift

  • Creates sheltered areas behind that often allows the formation of a salt marsh

  • Largest vegetated shingle spit in Europe

  • Stretches for about 10 miles

  • Located on the Suffolk coast

• Tombolo – Chesil Beach

  • Longshore drift forming a spit that connects an island to the mainland

  • Connects the isle of Portland to Abbotsbury

  • Largest tombolo in the United Kingdom

• 1.1.7. Sand dunes – Ainsdale Dunes, Sefton

  • On the northwest coast of England

  • Contains a range of habitats

  • Largest dune area in England

• Mudflat/ salt marsh – Morecambe Bay

  • Northwest coast of England

  • 310km^2 of intertidal sand flats

  • Salt marshes develop along the bays margins

  • Makes Morecambe bay a crucial habitat for wildlife

• Coral reef – Great Barrier Reef

  • Located north-east of Australia

  • Made up of 2900 individual reefs and 900 islands

  • Threatened by human activity which causes bleaching of coral (global warming)

• 1.1.8. High energy event – December 2013 storm (UK East coast)

  • Gale-force winds of up to 100mph

  • Sea levels peaked at 5.8km and 4.7m in Hull and Dover respectively

• Rias – Kingsbridge Estuary, Devon

  • A river valley at the coast that has been inundated by the sea as relative sea level rises, resulting in a “drowned valley”

  • Formed on a submergent coastline

  • Has very little freshwater input, high salinity levels and a large tidal range

  • Supports diverse intertidal habitats (mudflats and salt marshes

  • Has steep banks and a relatively deep channel compared to its width

• Fjord – Sognefjorden, Norway

  • A glaciated valley at the coast that has been inundated by the sea. Has steeper rising walls, a straighter long profile and is deeper than a ria due to glaciers over-deepening the valley

  • Formed on a submergent coastline

  • Located in western Norway

  • 205km long, and up to 4,5km wide

• Raised beach – Isle of Arran, Kings Cave

  • Raised beaches are shore platforms and beaches that are found stranded above the present-day high tide level

  • Formed on an emergent coastline

  • Located in Scotland

  • Kings cave is a notable area which provides evidence of the past sea levels

  • Flat shore platform elevated above the current coastline

• 1.1.9 [Case study] Management of coastal processes – Holderness

  • Located in East Yorkshires coastline

  • Composed predominantly of soft erodible boulder clay

  • Notoriously one of Europe’s fastest eroding cliffs (over 2m/year)

  • Use of sea walls, groynes and revetments

  • Use of managed retreat in certain areas

  • Integrated coastal zone management

  • Decision making involves tradeoffs between protecting property and allowing natural coastal change

• 1.1.10 [Case study] Management of human activity – Ainsdale sand dunes

  • Designated as a national nature reserve and site of special scientific interest (SSSI)

  • Threats from trampling by visitors, off road vehicles and cycling, urban development (encroaching)

  • Managed by fencing and boardwalks, sand dune stabilisation and education and signage

Changing Places

• 1.3.1 Overall characteristics of your ‘home’ place (can be Manchester or more specific e.g. Tottington)

  • Located in the northwest of England

  • Close to other major cities such as Liverpool and Birmingham

  • Population of around 551,900 as of 2021

  • Very high population density

  • Grew rapidly in the early 1800s

• 1.3.2 AONB: LDNP, media representation of Manchester

  • News- shows both positive (eg infrastructure developments) and negative (eg crime statistics) facets of Manchester

  • Literature- frequently explores themes of resilience, social change and the impact of industrial heritage

  • Music- Manchester is famous for music with bands such as the smiths and oasis, and is frequently cited as the birthplace of influential music trends

• 1.3.3 External factors influencing economic restructuring: Ebbw Vale

  • Valleys initially chosen due to a large amount of coal, labour from nearby towns and location close to the coast (for trade)

  • Restructured due to:

    • Limited resources

    • Chester imports to coastal steel works

    • Political decisions to close coal mines

    • Government grant to relocate

    • Economies of scale- unable to keep up

    • Globalisation

    • Lifestyle changes

• 1.3.4 Consequences of loss of primary industries in rural areas e.g. Ebbw Vale

  • 70,000 jobs lost

  • Decline in small businesses

  • Less tax going to council

  • Became 2nd most deprived town in the uk

  • Landscape damage

• Government policies in deindustrialised places e.g. Salford Quays, Manchester (this case study can also be used for urban rebranding, urban reimaging, and urban regeneration)

  • Needed rebranding after the 1982 closure of Manchester Docks

  • Focus of the regeneration was to boost the local economy and enhance residents quality of life

  • Significantly boosted the local economy by attracting investment, creating jobs and increasing property values

  • Has become a cultural and entertainment destination

• 1.3.5 Just need examples to support points such as an example of Out-of-Town retailing can be The Trafford Centre

• 1.3.6 Quaternary industry – Silicon Valley, California and Tech City, London, UK

• 1.3.7 Rural rebranding project – Eden Project/ Glastonbury Festival/ Shrewsbury/ Farmer Ted’s (just need to know one but two would be good so you can make comparisons between them)

  • Glastonbury

    • Annual 5day performing arts festival located in Pilton (Somerset)

    • Founded by a community group

    • Creates a large amount of tourist income, however it can cause a lot of pollution, including noise pollution

  • Eden project

    • Visitor attraction in Cornwall

    • Consists of two large enclosures that house thousands of plant species

    • Created by the government and charities

    • Has generates £1.9 billion for the local economy since 2001

• 1.3.8 Just need examples to support points such as 50% of homes in Beadnell, Northumberland are second homes

• 1.3.9 Just need examples to support points such as an example of a culture-led regeneration scheme is Lowry theatre, Salford quays

• 1.3.10 Just need examples to support points such as an example of a Fast Growth City is Cambridge

Coasts:

1.1.1 the operation of the coast as a system;

• A system is a collection of interrelated parts that work together in an environment.

• They have inputs, outputs, and stores of energy and matter

• Material and energy is transferred by a range of processes

• Most systems share some of the same characteristics

  • They have boundaries, but this can be conceptual rather than physical

  • They have inputs and outputs of material that becomes processed within the system

  • They involve the movement of material and energy in between components

• Closed systems- transfers ff energy into and beyond the barrier, but no transfer of matter, e.g. the earth

• Open systems- both matter and energy can be transferred from the system to outside the boundary, eg a rainforest ecosystem

• A system is said to be in equilibrium if the inputs and outputs have the same size of stores.

• Smaller systems within a bigger system are called subsystems.

  • Examples of systems include:

    • The water cysle

    • Landscapes

    • Human systems (companies)

    • Coasts

• Around 40% of the world’s population lives within 100km of the coast, hence they are very popular

• Natural processes that occur at the coast including wave action, flooding, coastal erosion and sedimentation can pose hazards to human occupation of the coast

• Globally, average sea level is rising by 3.4 mm y−1

• The three main processes which effects all coasts and the morphology of them are:

  • Sea level changes

  • Waves and currents

  • Coastal sediment transport

1.1.2 temporal variations:

1. Temporal Variations and Coastal Environments

• Temporal Variation: Refers to changes over time.

• Key Processes Influencing Coastal Environments:

  • Waves: Generated by wind friction causing ripples that grow into waves.

    • Energy moves, not water, in open seas.

    • Types of waves: oscillation waves (particle movement in circular/elliptical orbits).

  • Tides, Waves, Currents: Rapid processes impacting erosion, transport, and deposition.

2. Waves and Their Characteristics

• Wave Formation:

  • Wind blowing over the sea surface creates ripples, growing into waves with continued force.

  • Wave height depends on:

    • Fetch: Distance wind travels over water.

    • Wind Strength and Duration.

    • Sea Depth.

  • Types of Waves:

    • Constructive Waves:

      • Long wavelengths, low height.

      • Strong swash deposits material, forming berms.

    • Destructive Waves:

      • Short wavelengths, high height.

      • Strong backwash erodes the beach.

      • Steep beach profiles.

  • Wave Behavior Near Shore:

    • As depth decreases:

      • Circular motion transitions to elliptical.

      • Wave height increases, wavelength decreases.

      • Wave steepens and breaks.

3. Currents

• Definition: Identifiable water flows operating in the coastal zone.

• Types:

  • Tidal Currents:

    • Rise (flood currents) → Transport material towards the shore.

    • Fall (ebb currents) → Remove material offshore.

  • Rip Currents:

    • Water flows back to the sea, often at high speed.

  • Longshore Currents:

    • Waves approach at oblique angles, causing sediment transport (longshore drift).

  • Tidal Bore:

    • A turbulent wall of water moving upstream in narrow areas.

4. Tides and Their Influence

• Tides: Controlled by gravitational forces of the Moon (primary) and Sun (secondary).

• Types of Tides:

  • Spring Tides:

    • Moon, Earth, and Sun aligned → Higher tidal range.

  • Neap Tides:

    • Moon and Sun at right angles → Lower tidal range.

• Tidal Range:

  • Vertical distance between high tide and low tide.

  • Classifications:

    • Micro-tidal: <2m (e.g., Eastern Australia).

    • Meso-tidal: 2–6m.

    • Macro-tidal: >6m (e.g., UK coasts, Bay of Fundy).

  • Effects on Geomorphology:

    • Macro-tidal: More depositional features, sand dunes, and salt-weathering.

    • Micro-tidal: Well-defined erosional features (e.g., wave-cut notches).

5. Coastal Processes and Features

• Constructive vs. Destructive Waves:

  • Constructive: Gentle beach profiles; Summer waves; Beach building.

  • Destructive: Steep beach profiles; Winter waves; Beach erosion.

  • Breaking Waves:

    • Spilling: Gentle slope, strong swash.

    • Plunging: Steep slope, strong backwash.

    • Surging: Do not break fully, slide along the shore.

• Tidal Influences on Landforms:

  • High tidal ranges expose a larger area to wave action, leading to diverse geomorphological features.

    • Low tidal ranges focus wave energy in a narrow zone, intensifying erosion.

6. Key Concepts

• Wave Base: Depth below which waves cease to have orbital motion.

• Energy Inputs: Waves, tides, and currents are primary energy drivers shaping coasts.

• Sediment Transport: Both deposition (berms, dunes) and erosion (notches, cliffs) are influenced by wave and tidal action

1.1.3 Landforms and landscape systems, their distinctive features and distribution

• High energy landforms

  • Headlands and bays

  • Cliff erosion

  • Shore platform

  • Cave arch stack stump

• Low energy landforms

  • Sand dunes

  • Tombolos

  • Spits/bars

  • Mud flats/ salt marshes

• Coasts are a dynamic open system

  • They receive inputs from outside the system and transfer outputs away from the coast and into other systems.

• Sediment cells

  • Movement of material is largely self-contained

  • The flows of sediment act in dynamic equilibrium.

    • Dynamic equilibrium refers to the maintenance of a balance in a natural system, despite it being in a constant state of change

      • Inputs

        • Marine: Waves, Tides, Salt Spray

        • Atmosphere: Sun, Air Pressure, Wind Speed and Direction

        • Humans: Pollution, Recreation, Settlement, Defences

      • Outputs

        • Ocean currents

        • Rip tides

        • Sediment transfer

        • Evaporation

        • Stores/sinks

        • Beaches

        • Sand Dunes

        • Spit

        • Bars and Tombolos

        • Headlands and Bays

        • Nearshore Sediment

        • Cliffs

        • Wave-cut Notches

        • Wave-cut Platforms

        • Caves

        • Arches

        • Stacks

        • Stumps

        • Salt Marshes

        • Tidal Flats

        • Offshore Bands and Bars

1.1.4- factors affecting coastal processes and landforms:

Waves and Energy Transfer

• Wave Energy Depends On:

  • Wind velocity

  • Wind duration

  • Fetch (distance of open water wind blows over)

  • Orientation of the coastline

  • Water depth

• Largest Waves Form:

  • Long fetch (e.g., southwest and west fetch of 320 km)

  • High wind velocity and duration.

Clapotis Effect

• Occurs along rocky coastlines with deep offshore water.

• Reflected waves interact with incoming waves to create standing waves.

• Found on steep beaches or against sea walls.

Lithology and Rock Types

• Lithology: Refers to the rock’s make-up (composition, hardness, permeability).

• Rock Types:

  • Igneous:

    • Formed by cooling magma/lava.

    • Hard, resistant, impermeable (unless joints or chemical weathering occur).

  • Sedimentary:

    • Formed by compressed sediments.

    • Soft, porous (e.g., sandstone), but clay/shales are impermeable.

  • Metamorphic:

    • Formed by heat/pressure altering other rocks.

    • Hard, resistant, often impermeable unless jointed.

Factors Influencing Coastal Erosion

• Hardness of Rocks:

  • Hard rocks (igneous/metamorphic) resist erosion; soft rocks (sedimentary) erode faster.

• Permeability:

  • Permeable rocks (e.g., chalk) support vertical cliffs but erode via subaerial processes.

  • Impermeable layers (e.g., clay) below permeable ones cause lubrication, mass movement.

• Physical Structure:

  • Joints, bedding planes, and faults weaken rocks, increasing erosion rates.

• Chemical Composition:

  • Silica-rich rocks (e.g., quartzite) resist chemical weathering.

  • Rocks prone to oxidation, hydrolysis, and carbonation (e.g., limestone) erode faster.

Geological Structure

• Strata: Layers of sedimentary rock with bedding planes.

  • Thinly bedded rocks (e.g., shale) erode faster than thickly bedded rocks.

• Joints: Vertical cracks that allow water and erosion processes to penetrate.

• Folding and Faulting:

  • Faults create weak zones; folding alters cliff profiles based on dip angle.

Coastline Types

• Discordant Coastlines:

  • Perpendicular rock bands create headlands and bays (e.g., Dorset coast).

  • Hard rocks resist erosion; soft rocks form bays.

• Concordant Coastlines:

  • Parallel rock bands protect softer inland rocks.

  • Breached outer hard rock creates coves (e.g., Lulworth Cove).

Marine Factors

• Destructive waves (high energy): Erode coasts rapidly.

• Constructive waves (low energy): Deposit sediment.

• Climatic Influence:

  • Seasonal storms and climate change increase erosion.

Human Factors

• Coastal management (e.g., sea walls) reduces erosion locally.

• Pollution and recreation impact natural processes.

Summary of Influences on Coastal Erosion

• Macro Scale (Global):

  • Lithology dominates.

  • Rock type defines resistance to erosion.

• Meso Scale (Regional):

  • Geological structures (joints, faults, permeability) are crucial.

• Micro Scale (Local):

  • Human activity can accelerate or mitigate erosion.

Key Interactions

• Lithology + Marine Factors: Rock type determines how wave energy impacts the coast.

• Human Activity + Natural Factors: Coastal defenses alter erosion and deposition patterns.

• Climatic Events: Episodic storms and long-term sea level rise exacerbate erosion.

1.1.5 processes of weathering, mass movement, erosion and landforms:

• Weathering- breaking down of rocks with no additional force acting on the rocks

  • - can be subaerial or aerial.

    • Subaerial- within the air, combination of weathering and mass movement

      • Physical

        • Wetting and drying

        • Salt crystallisation

        • Freeze thaw

          • Repeated, happens year after year.

      • Chemical

        • Hydrolysis

        • Oxidation

        • Solution

        • Carbonation

      • Biotic

        • Plants

        • Animals

    • Marine

      • Below the water

        • Abrasion- rocks scraping into the cliff, braking rocks off

        • Hydraulic action- force of the water compressing air into the gaps in the rocks.

        • Attrition- rocks hitting into each other below the water, becoming smaller and more rounded

        • Corrosion- rocks erode as weak acids in seawater dissolve/react with them.

• Mass movement

  • Rapid, episodic

  • Variable speed

  • Slow speed

• Slumping- unconsolidated rock detaches at the cliff face and slides down onto the shore, usually due to a layer of lubrication between absorbent and non-absorbent rocks.

  • Often associated with clay cliffs

  • Fallen material remains as an identifiable mass until further erosion acts upon it

• Mudslides- fine sediment mixes with large amounts of water, becoming saturated and flowing down the slope.

  • Unconsolidated rock

• Rockfalls- rock fragments break away from the cliff face and either drops vertically or bounces down the slope.

  • Usually occurs in massively bedded rock that experiences freeze thaw weathering

  • Fallen rocks form scree at the base of the cliff

• Soil creep- when water in soil freezes, expands, and melts, moving down a slope due to the force of gravity.

  • Repeats year after year, bending further down the slope

• Landslides- blocks of rockslide down a plane, usually due to the rainwater making the rocks heavier, or a lack of friction between the layers of rock.

  • Slide plane- line of weakness in the rock

• High energy environments- often have:

  • Destructive waves

  • Marine erosion

  • Steep cliffs that are eroded quickly.

  • Erosional landforms, such as

    • Cave, arch, stack, stump.

    • Headlands and bays

      • Occurs on discordant coastlines, where different types of rock erode at different rates

    • Geos

    • Blowholes

    • Shore platform

    • Cliffs

1.1.6 Coastal Transport and Associated Landforms:

• The coastal system

  • Open system

  • Around 90% of sediment on the beach is from rivers

    • Inputs

      • Beach nourishment

      • Cliff and dune erosion

      • River sediment

      • Longshore transport

      • Onshore sediment transport

    • Outputs

      • Longshore transport

      • Dredging & sand mining

      • Wind and storm over wash

      • Offshore sediment transport

    • Beaches are the store of material, with spits and dunes acting as sinks

    • The beach system is in dynamic equilibrium when there is few inputs and losses

• Transport

  • Determined by the speed of the water and the size of the sediment

    • Traction- the rolling or dragging of large rocks along the sea floor

    • Saltation- smaller rocks are bounced along the sea floor

      • Creates positive feedback as the sediment can hit into more sediment, dislodging it from the sea floor

    • Suspension- smaller particles are held in the water

    • Solution- solvable material is dissolved and moves with the water

    • Flocculation- clay particles stick together (aggregating)

      • Increases the mass so that they can be deposited to create salt marshes and mudflats

  • Longshore drift – swash brings material up at an angle dictated by the prevailing wind, and the backwash carries it back in a zigzag fashion at right angles to the coastline

    • Responsible for moving substantial amounts of sediment along the coast

    • The direction the sediment moves in is dictated by the direction of the prevailing wind

    • Occurs with low energy constructive waves

      • Groynes stop longshore drift to help build up the beach, however they can starve the beach further down the coast

        • This is known as terminal groyne syndrome

• Deposition

  • Occurs when the energy of the transporting water becomes too low to continue to carry the sediment, causing it to fall to the sea floor

  • (Flocculation) – speeds up deposition as it increases the fall velocity

  • Larger sediment such as rocks and boulders are moved during storms leading to the beach having larger sediment towards the back, as it is not reached by daily tides

  • The particles moving along a beach will become more rounded and smaller moving in the direction of longshore drift

  • The slope of the beach will also get shallower

    • Swash aligned beaches- forms when waves break parallel to the coast

    • Drift aligned beaches- longshore drift moves material along the coast

    • Sand dunes- form when dry material from flat open beaches is blown inland

    • Mudflats and salt marshes- formed of finer clay material which flocculates in the shallow water of estuaries

  • The Hjulstom curve

    • Logarhytmic graph which shows the flow speed and particle speed necessary for erosion, transport, and deposition

      

• Triangular graphs for beach material

  

• Depositional landforms

  • Beaches- loose unconsolidated material that has been transported and deposited by the sea

    • Runnels- dips in the beach in the foreshore zone

    • Littoral zone- area where land is subject to wave energy

    • Berms- raised barrier that coincides with the high tide line

      • Formed by constructive waves during calm weather

        

    • Bars and barrier islands

      • Bars- linear ridges of shingle extending across a bay

      • Attached to land on either side

      • Can be hundreds of kilometres long

      • Formed by longshore drift

    • Barrier island- where an area of sand has been formed by wave and tidal action parallel to the mainland coast

    • Cuspate forelands- triangular extension of the shoreline formed by longshore drift acting in two different directions that meet in the middle

    • Spits- when a sudden change in the coastline occurs but longshore drift continues to carry material, leading to a beach which extends out to sea

      • A secondary wind may cause the distal end to change shape

      • Salt marshes may form behind a spit as it becomes a sheltered area with a lot of deposition

    • Tombolos- one or more sandbars or spits that connect an island to the mainland

1.1.7 Aeolian, fluvial and biotic processes:

Aeolian Processes

• Definition: Movement of sediment by wind through erosion, transportation, and deposition.

• Common Environments: Coastal zones, deserts, and agricultural fields.

Transportation Mechanisms

• Suspension: Fine particles (<0.2mm) carried by the wind.

• Saltation: Medium particles (~0.2–2mm) bounce along the ground, predominant in coastal areas.

• Creep: Large particles rolled or pushed along the surface by wind.

Formation of Sand Dunes

• Conditions for Formation:

  • Abundant sand supply.

  • Low beach gradient.

  • Macro-tidal range.

  • Strong, consistent onshore winds.

  • Space for inland development.

  • Stabilizing vegetation like marram grass.

• Process:

  • Wind reaches critical velocity, lifting and transporting sand.

  • Sand accumulates in areas of low wind energy (e.g., behind obstacles or vegetation).

  • Forms dunes with a gentle windward slope (stoss) and a steep lee slope.

• Dune Development Stages

  • Embryo Dunes: Small dunes formed by sand accumulation around pioneer plants.

  • Foredunes: Stabilized by vegetation trapping more sand.

  • Yellow Dunes: Migration of sand grains forms larger dunes.

  • Grey Dunes: Stabilized dunes further inland with dense vegetation.

  • Slacks: Low areas between dunes, potentially water-filled due to the exposed water table.

Factors Affecting Dune Systems

• Sediment Supply:

  • Insufficient supply leads to erosion (blowouts).

  • Net sediment gain results in additional dune ridges.

• Vegetation:

  • Traps sand and stabilizes dunes.

  • Loss of vegetation creates positive feedback, increasing wind erosion.

• Fluvial Processes in Estuarine Environments

  • Definition: Interactions between river and tidal processes in estuaries.

  • Dominant Process: Deposition of sand and mud in low-energy environments, forming sediment sinks.

• Sediment Sources

  • Fluvial/Glacial: Material transported from rivers or glaciers.

  • Estuary Margins: Locally eroded sediment.

  • External Sources: Marine deposition, cliff erosion, and longshore drift.

• Landforms

  • Tidal Flats:

    • Muddy, sandy, or shelly; formed by settling fine sediments.

    • Colonized by pioneer plants, which trap sediment and increase elevation.

  • Salt Marshes:

    • Composed of deep mud; host vegetation adapted to low oxygen and saline conditions.

Biotic Processes in Mangroves and Coral Reefs

• Overview: High biodiversity ecosystems in tropical zones due to sunlight and warm temperatures.

Mangroves

• Definition: Salt-tolerant trees and shrubs in intertidal zones.

• Role:

  • Trap sediment and stabilize coastlines.

  • Provide habitats for diverse marine life.

Coral Reefs

• Definition: Calcium carbonate structures formed by coral organisms.

• Distribution: Found between 30° N and 30° S.

  • Warm-Water Corals: Thrive in water >15°C.

  • Cold-Water Corals: Found in deep, cooler waters like the North Atlantic.

• Ideal Conditions:

  • Temperature: 28–29°C.

  • Salinity: 32–42%.

  • Depth: Shallow water (<25m) for light penetration.

  • Alkaline water.

Importance:

• Carbon sink and habitat for 25% of marine species.

• Natural barriers against storms.

• Example: Great Barrier Reef, a major biodiversity hotspot supporting 450 million people globally.

Key Interactions

• Aeolian and Fluvial: Combined sediment transport shapes coastal and estuarine environments.

• Biotic Influences: Vegetation (e.g., mangroves) and coral reefs stabilize landforms and provide ecosystem services.

• Human Impact:

  • Vegetation loss accelerates erosion.

  • Coral reefs face threats from pollution and climate change

1.1.8 variations in coastal processes:

1. Coastal Processes and Timescales Coastal processes, such as erosion, deposition, and sediment movement, occur over a wide range of timescales. These can range from rapid, short-term changes lasting seconds, minutes, or hours, to long-term processes that take years, decades, and even millennia. Some examples of these processes are:

• Seconds/Minutes/Hours:

  • Sediment movement by wind or water

  • Cliff falls

  • Tidal cycles, which can cause noticeable shifts in beach profiles

  • Storm surges, which cause temporary flooding and erosion

• Days/Weeks/Months/Years:

  • Beach erosion and adjustments to the shore profile, such as the movement of sediment and sand

  • Longshore drift, which transports sediment along the coastline

  • Erosion and deposition, including the formation of new habitats and coastal landforms

• Decades/Millennia:

  • Changes due to eustatic (global) and isostatic (local) sea-level changes, such as the gradual formation or erosion of coastlines, often over long geological periods.

These processes interact to shape coastal landscapes, making them dynamic and constantly changing.

2. Human and Physical Causes of Coastal Changes Coastal changes are influenced by both human and physical factors:

• Human causes: The construction of buildings, roads, and other infrastructure along the coastline can disrupt natural processes like sediment movement and the ability of ecosystems to adapt. The lack of sea defences, particularly in areas with high population density, can also lead to greater damage from storms, erosion, and flooding.

• Physical causes:

  • Storm surges caused by low-pressure weather systems, which push water toward the coast, increasing the risk of flooding.

  • High tides that can exacerbate the effects of storms and lead to coastal erosion.

  • Climate change, which contributes to more frequent and intense weather events, increasing the likelihood of destructive coastal impacts.

3. Seasonal and Long-Term Coastal Changes Coastal changes are also linked to seasonal variations, as well as much longer-term shifts:

• Seasonal changes:

  • In summer, calmer weather and smaller, less destructive waves allow the beach to build up. These waves deposit sand and sediment, creating wider beaches with gentle slopes.

  • In winter, more intense storms bring larger, destructive waves that erode the beach and create steeper beach profiles. This process, known as destructive wave action, often causes the beach to lose sediment, with materials being carried offshore.

• Changes over millennia:

  • Eustatic changes involve global shifts in sea levels, primarily driven by changes in climate and tectonic movements. When global temperatures rise, ice sheets melt, adding more water to the oceans, leading to a rise in sea level. Conversely, cooling periods cause water to be trapped in ice sheets, lowering sea levels.

  • Isostatic changes occur on a more regional scale, usually as a result of the Earth's crust adjusting due to the weight of ice sheets during glaciation or after the ice sheets melt. For example, land that was previously compressed under heavy glaciers will slowly rise in a process called isostatic rebound, a phenomenon evident in places like Scotland, where the land is still recovering from the last Ice Age.

4. Sea-Level Change and Climate Change Sea levels have fluctuated significantly over geological time. Since the end of the last Ice Age, sea levels have risen by about 130 meters. More recently, global sea levels have been rising at a rate of about 2mm per year and are expected to accelerate to 8-16mm per year by 2100 due to climate change and ongoing greenhouse gas emissions.

The impacts of rising sea levels include:

• Increased flooding of coastal areas: With higher sea levels, low-lying areas are more prone to flooding. For example, the frequency of flooding at King's Point, New York, nearly doubled from 1995-2004 to 2005-2014.

• Submergence of islands: Low-lying islands, such as the Maldives, are at risk of being submerged if sea levels rise by 0.5 meters.

• Coastal erosion: Rising sea levels and stronger storms are leading to more erosion, threatening ecosystems, infrastructure, and human settlements.

5. Landform Changes from Sea-Level Variations Sea-level changes can significantly alter coastal landforms:

• Marine regression (a fall in sea level) leads to emergent coastlines. As sea level drops, previously submerged features like beaches, cliffs, and platforms are exposed above the water. This is seen in raised beaches and fossil cliffs, where ancient coastal features are now high and dry, far above present-day sea levels.

• Marine transgression (a rise in sea level) causes submerged coastlines, where landforms like beaches and estuaries are inundated by rising seas. This can lead to the creation of rias (drowned river valleys) and fjords in some areas. As the sea advances, ecosystems such as salt marshes, mangroves, and coral reefs may be pushed inland.

6. Key Concepts and Terminology

• Thermal expansion: As the Earth's climate warms, ocean water expands, contributing to rising sea levels.

• Glacio-isostacy: This refers to the depression of the Earth's crust due to the weight of glaciers during glacial periods, followed by rebound when the ice melts.

• Hydro-isostacy: The weight of additional water in an ocean basin causes the ocean floor to sink. This is a key consideration in understanding the impact of rising sea levels due to melting ice sheets.

Examples of Coastal Impacts

• Storm surges: Severe storm surges, like those that hit the UK in 1953 and more recently, have caused significant damage to settlements, eroded coastlines, and overwhelmed flood defences. These surges are expected to become more frequent and intense as climate change progresses.

• King's Point flooding: As sea levels rise, areas like King's Point, NY, have experienced an increasing frequency of coastal flooding. From 1995-2004, the area flooded around 80 times; from 2005-2014, it flooded nearly 160 times, showing a clear trend towards more frequent flooding events.

• The Maldives: Rising sea levels pose a grave threat to low-lying islands like the Maldives, where a rise of just 0.5 meters would submerge large areas, displacing communities and disrupting local ecosystems.

1.1.9- coastal processes as a vital context for human activity:

Positive Impacts of Coastal Processes on Human Activity

• Tourism

  • Coastal areas are popular tourist destinations, drawing people for recreational activities and beautiful landscapes.

  • Example: In Blackpool (UK), the coast generates £855 million annually, supporting 20,000 jobs.

  • Coastal landforms such as beaches, cliffs, and dunes attract visitors.

  • Longshore drift and deposition contribute to beach formation, which is crucial for tourism.

  • Tourism boosts local economies, especially in areas with beautiful, sunny climates (e.g., Florida, Mediterranean)

  • Seasonality: Majority of the tourism occurs in the warmer months (April to September) when conditions are favorable for beach activities.

• Economic Development

  • Coastal processes create natural harbors, vital for trade, shipping, and the fishing industry.

  • Example: Poole Harbour, Dorset, supports trade and shipping, adding to local economic growth.

  • Development of coastal infrastructure, like resorts and hotels, brings in foreign investment (FDI) and supports employment.

  • Coastal settlements: Attract businesses in sectors such as hospitality, transportation, and services.

• Recreation and Quality of Life

  • Activities like swimming, fishing, surfing, and boating are central to coastal recreation, which is a major economic driver.

  • Coastal regions offer unique experiences in eco-tourism, such as in the Galapagos Islands and the Maldives.

  • Local businesses (e.g., tour operators, hotels) thrive due to coastal recreation and tourism.

  • Coastal areas provide high-quality living environments, attracting both tourists and permanent residents.

Negative Impacts of Coastal Processes on Human Activity

• Coastal Erosion

  • Coastal erosion, particularly in soft cliff areas like Holderness Coast (UK), has severe consequences.

  • Erosion leads to property loss (homes, farms) and damage to infrastructure (roads, utilities).

  • Example: On the Holderness Coast, 30 villages have already been lost, with more at risk.

  • Social impacts: Erosion leads to displacement, difficulty obtaining insurance, and social disruption.

  • Economic impacts: Loss of agricultural land and infrastructure reduces economic stability.

• Disruption to Local Industry

  • Coastal processes such as sediment deposition and erosion can block harbors, reducing the flow of trade.

  • Example: Poole Harbour (Dorset) experiences sediment buildup that blocks shipping routes, affecting the fishing industry.

  • Sediment deposition also impacts local marine ecosystems, affecting fish stocks and other industries reliant on healthy coastal ecosystems.

• Loss of Agricultural Land

  • Coastal erosion leads to the loss of valuable agricultural land, which harms food production and local farming economies.

  • Example: On the Holderness Coast, 80,000 m² of farmland is lost each year, significantly impacting local farming.

Coastal Management Strategies

• Do Nothing

  • No action is taken to prevent coastal erosion; the coastline is left to erode naturally.

  • This is usually done when land has low value, and there's no need to protect it from erosion.

  • Can result in property loss and infrastructure damage in vulnerable areas.

• Retreat the Line

  • Allow coastal erosion to take place but relocate people and businesses further inland from the coastline.

  • Example: Used in areas where land is less valuable, and relocation is feasible, often with compensation for affected individuals.

• Hold the Line

  • Use physical defenses (e.g., seawalls, groynes, and breakwaters) to prevent coastal erosion and protect valuable land.

  • Example: At Bridlington and Hornsea (Holderness Coast), sea defenses are used to protect residential areas and vital infrastructure.

  • This is expensive and often used in areas where critical infrastructure, such as gas terminals or roads, needs protection.

• Limited Intervention

  • Implement some defensive measures to reduce erosion impacts but allow some natural processes to occur.

  • Adjustments might include planting vegetation or building small-scale barriers.

  • This strategy works when a balance between natural processes and human activity is desired, but resources for full defense measures are limited.

Conclusion

• Positive impacts: Tourism, economic growth through trade and recreation, and improvement in quality of life.

• Negative impacts: Coastal erosion, industry disruption, and loss of agricultural land pose significant challenges.

• Coastal management is necessary to balance the benefits of development with the protection of coastal environments. Different strategies are chosen based on the value of the land, infrastructure, and the potential social, economic, and environmental consequences.

1.1.10 the impact of human activity on coastal landscape systems:

• Coastal Management Must Be Sustainable

  • Coastal management strategies must aim to minimize environmental damage while balancing the needs of human activity. Sustainable management refers to managing the coast in ways that do not cause lasting damage to the environment or people's livelihoods.

• Hard Engineering

  • Hard engineering involves constructing solid structures (like seawalls, groynes, and breakwaters) to protect the coast.

  • Expensive and disrupts natural coastal processes, causing long-term environmental consequences.

• Soft Engineering

  • Soft engineering involves working with natural processes to protect the coast (e.g., creating sand dunes, marshland).

  • Cheaper and more environmentally friendly than hard engineering. These methods integrate with natural habitats and can support biodiversity.

• Sustainability of Soft Engineering

  • Soft engineering is more sustainable because it involves less disruption to the natural environment and reduces long-term costs. It also creates important habitats like marshes and sand dunes, which benefit both wildlife and human activity.

• Shoreline Management Plans (SMP)

  • The coastline is divided into sediment cells, where each cell is treated as an individual management unit. Each area is carefully managed to ensure that any coastal interventions don’t cause problems elsewhere in the sediment cell.

  • Key Elements of SMP:

    • Sediment Cells: These are stretches of the coastline where sediment transport is consistent, and the management plan for each area can affect others.

    • Options for Management: For each sediment cell, authorities may decide to:

      • Hold the Line: Maintain existing defenses.

      • Advance the Line: Build new defenses further out to sea.

      • Retreat the Line: Allow the coast to erode and move communities or infrastructure inland.

      • Do Nothing: Let natural coastal processes take their course

    • Cooperation: Local authorities within a sediment cell must work together to create a unified SMP, ensuring a coordinated approach to coastal management.

• Integrated Coastal Zone Management (ICZM)

  • ICZM considers all aspects of the coastal zone, including land, water, people, and the economy.

  • Key Features of ICZM:

    • Holistic Approach: Views the coastal system as interconnected; land and water are interdependent.

    • Consideration of Multiple Uses: Balances different uses of the coastline, such as fishing, tourism, industry, and conservation.

    • Multilevel Governance: Involves input from local, regional, and national authorities.

    • Dynamic Strategy: Decisions are revisited and adjusted as environmental conditions or human demands change.

Negative Impacts of Human Activity on Coastal Processes and Landforms

• Offshore Dredging

  • Dredging involves removing sediment from the seabed, often for use in construction or to improve shipping channels.

  • Impacts:

    • Seabed damage: Dredging can disturb the seabed and affect marine life.

    • Marine habitat destruction: It can harm ecosystems, particularly those dependent on filter feederslike mussels.

    • Eutrophication: Dredging releases nutrients into the water, which may cause algal blooms, leading to ecological damage.

    • Sediment displacement: Can alter water flow and coastal dynamics, affecting erosion and deposition patterns along the coast.

• Sand Dune Erosion

  • Sand dunes are fragile ecosystems, and human activities can significantly damage them.

Human Impacts on Sand Dunes:

• Conversion:

  • Urbanisation and development can alter the natural vegetation of dunes, making them more vulnerable to erosion. Dunes lose their function if sediment cannot move naturally or they are built on.

• Removal:

  • Sand may be removed for construction purposes (e.g., glass-making), or dunes may be altered to make space for tourism developments, such as beach access points.

• Utilisation:

  • Tourism often leads to overuse of dunes, where walking and activities cause physical damage to the dunes. In some cases, dune conservation efforts, such as artificial blowouts to promote grass growth, can have unintended negative effects, increasing erosion.

• External Impacts:

  • Dunes rely on a constant supply of sediment to maintain their structure. If this sediment is disrupted (e.g., by coastal defenses or construction projects), dunes can no longer build or migrate, leading to their degradation.

Changing places

1.3.1 relationships and connections:

• Definition of place- a portion of geographic space to which meaning has been given by people. A place may have uniqueness and distinctiveness as a result of the way it has developed and changed. It is shaped by the relationships to other places and spaces at a range of scales

• The geographical concept of a place has three different aspects:

  • Location- where a place is on a map- its latitude and longitude

  • Locale- each place is made up of a series of locales where everyday life activities take place, for example an office, home, park, church. These locales dictate out social interactions and help forge attitudes, values and behaviours

• Factors that shape the characteristics of a place:

  • Time- where the place fits along a timeline, is it modern?

  • Identity- features that make the place unique

  • Representation- communicating something specific about a place, how is it shown?

  • Threshold- population required to sustain services

    • Endogenous factors- the internal factors that shape a place

    • Exogenous factors- the external factors that can shape a place

• The demographic, socioeconomic and cultural characteristics of places are shaped by factors including shifting flows of people, resources and investment. Places change overtime and develop layered history. This history helps to shape the identity and personality of a place. The identity is also shaped by the relationship to other places at a range of scales

• Worldwide interdependence- occurs due to the nature of the modern global economy, trade patterns and communications

• Globalisation- the process by which the world is becoming increasingly interconnected as a result of massively increased trade and cultural exchange

Place is a part of everyone’s life and we all give places different meanings. Its identity will be seen differently by different age groups, genders, and those who seek to manage and represent the place on our behalf.

People have become attached to places at a variety of scales

Places are increasingly interdependent as a consequence of globalisation

1.3.2 meaning and representation:

• Places are given meaning due to people’s perception, engagement and their attachment to the place

• AONB is an area of England, Wales and Northern Ireland which have been designed for conservation due to its natural landscape value, eg Chichester Harbour

  • Farmers perceive CH as a source of income and an area of natural beauty, they may have conflict with tourists.

  • Environmentalists perceive CH as an area of natural beauty and an area that needs protecting, they may have conflict with locals and boating clubs.

  • Boating clubs perceive CH as a source of income and enjoyment, they may have conflict with environmentalists

  • Tourists perceive CH as a place to go on holiday and a place of beauty however, they may feel that they are not involved with the community

  • Second home owners perceive CH as a way to make money from renting their house. Unfortunately, it creates competition for houses.

  • Local businesses perceive CH as a way to sell their goods or provide a service. However, big businesses may push little companies out

  • Local residents perceive CH as an area of safety and a sense of community, But, they may have conflict with environmentalists

• Media representation

  • Different groups use the media to advertise and promote the city of Manchester. Individuals can also represent a place, through social media such as Facebook and Instagram.

    • City council is the party in political power; they use the media to maintain profile of the city. Their desired outcome is urban development

    • Manchester is represented in the Visit Manchester website as place with a sense of community and diversity. It portrays Manchester in a positive manner.

    • Manchester’s representation in the news focuses on local culture and the development of the city as well as negative events such as crime

    • Manchester’s representation in literature is subjective as it varies based upon peoples’ personal experiencing with the place.

    • Manchester’s representation in history portrayed Manchester as having a range of global influences through business (e.g. textiles - Cottonopolis, Warehouse City), ideas (e.g. Suffragette movement), science (e.g. atomic theory), inventions (e.g. Alan Turing, the Spinning Jenny), literature (e.g. A Clockwork Orange, Anthony Burgess), entertainment (music, sport, TV).

• Place profile is variety of field work techniques to provide a composite picture of social, economic and environmental facets of a place you are studying

• Formal information: Objective, geospatial and statistical based info e.g. census data, maps, official reports

• Informal data: Subjective, open to interpretation and can vary greatly between sources e.g. local newspaper reports, art, music

1.3.3 changes over time in the economic characteristics of a place

• Primary sector: The part of the economy useful for collection and use of natural products - e.g. Ethiopia

• Secondary sector: The manufacturing or industrial sector-processes resources into goods – e.g. Indonesia

• Tertiary sector: The sector that enables goods to be traded and services to be offered – e.g. China

• Quaternary sector: Sector for research, ICT and processing of information – e.g. Germany

• External forces influencing economic restructuring: The Works, Ebbw Vale

  • Steelworks, originally located in the valleys of South Wales (Merthyr Tydfil and Ebbw Vale), from 1990s onwards, found on the south coast in Port Talbot (east of Swansea)

  • Original location factors: coal in the valleys and iron ore and limestone. Labour from towns such as Ebbw Vale. Rivers provided power to drive water wheels. Near coast for exports of steel.

• Factors leading to economic restructuring:

  • Limited resources available in original location: (iron ore, coal), cheaper imports to coastal steel works. More raw materials readily available in the valleys

  • Political decisions to close coal mines i.e. local (Blaenau), regional (Wales) and International (Special Areas Act 1934). Government offered grant to relocate.

  • Economies of scale: unable to compete with large, coastal plants, nationally and globally.

  • Globalisation: Port Talbot offered the potential to import raw materials and export steel across the world, the railway and M4 are close to PT

  • Lifestyle changes: Greater emphasis placed on education and skill development, environmental protection and sustainability in the new wetlands

  • Boosterism: Use of publicity to promote the image of modernity, represented by new activities

• Effects of restructuring:

  • Impact on valleys: 70,000 jobs lost, less economic activity, less tax going to council, less investment, out migration, decline in small businesses, became the 2nd most deprived town in the UK, landscape damage

  • Impact on PT: more direct jobs (Tata Steel= 3,500 jobs) 1,500 indirect jobs created, economic development- but many jobs low paid, multiplier effect in the town as support services attracted to the area, local infrastructure improved increase in population size, most polluted town in Wales, coastal habitats damaged, steelworks creates an eye sore for local population.

• Decline in primary employment in a rural area: UK coal industry

• Decline in secondary employment in an urban area: Manchester textile industry

  • The Clark Fisher Model provides a basic explanation of the changing balance of employment in developed economies over time.

  • The decline of the manufacturing industry in the UK and other developed economies is a consequence of factors emanating from both beyond the country and within the country/region.

  • Deindustrialisation has been a significant outcome of the decline in manufacturing and has had a variable impact on places. It has given rise to inequalities both within and between towns and cities.

1.3.4 economic change and social inequalities in deindustrialised urban places

• Causes of deindustrialisation

  • A fall in the output of manufacturing

  • The development of new products

  • The growth of cheaper imports of the same products

  • Drop in the number of employees due to machinery

• Consequences of decline in a secondary industry

  • Positive

    • A shift towards tertiary jobs

    • Technological advances improve and develop the industry

  • Negative

    • Jobless require benefits from the government

    • Unable to afford a basic standard of living and become homeless

    • Settlements close to secondary industries lose their identity and quality of settlements decline

    • Many left unemployed/ unable to find jobs due to lack of skills

• Consequences of deindustrialisation in urban areas

  • Deprivation

    • Measured by the proportions of poor-quality housing, unskilled workforce, poor health, weak transport links and so on.

    • These areas suffer from territorial stigmatisation as they are judged on its reputation and are perceived changes to the population mix of its neighbourhoods

    • Mostly perceived as ghettos due to the ethnic mix of people living there.

  • Social exclusion

    • To be outside of or marginalised from mainstream, society and the resources provided by them.

    • Usually involves stigma or disapproval of an individual/group e.g race, gender, sexuality, religion and age. It can be seen in people living in council estates, “no-go areas” due to criminality and places like new red light districts.

    • Homeless people are part of the “cycle of deprivation”- a sequence of events that disadvantaged people experience in which one problem leads to many more

  • Pollution levels and deindustrialisation

    • In 2013 fuel accounted for 88% of pollution.

    • Factories such as steelworks have been reduced to reduce sulphur dioxide.

    • Between 1970 and 2013 industrial combustion emissions fell by 94%

    • The UK aim to cut emissions by 26% to reach the Gothenburg Protocol.

• Government policies in deindustrialised places summary

  • Deindustrialisation affects economic diversity of places, which has a range of social effects, especially deprivation

  • Multiple deprivation will vary between and within places/regions. It can be statistically analysed using secondary sources from the census.

  • Rural areas have also lost employment in traditional primary industries.

  • Governments at the international, national and local levels have policies to mitigate the loss of employment and to create the opportunities for new employment.

  • Foreign Direct Investment: Investment made by a company based in another country e.g. The Shard, Malaysian investment in the redevelopment of Battersea

1.3.5 the service economy and its social and economic impacts

• Tertiary sector: The segment of the economy that provides services to its consumers, such as schools and restaurants.

• Quaternary sector: Industries that provide information services, such as computing, ICT, consulting and R&D

• Reurbanisation: The movement of people into the city centre as part of urban regeneration

• Gentrification: The process by which wealthier people move into, renovate and restore housing and businesses. It can occur in cities or deteriorated areas formerly home to poorer people.

• Factors that promote service sector growth

  • Technology: Quicker communication between businesses and customers

  • Prosperity: More disposable income leading to growth in leisure industries

  • Transport: Development of transport and transport links increases accessibility to areas beyond city centre

• How have city centres changed?

  • 72% of all highly skilled jobs are located here

  • 21% more productive than non-urban areas

  • Graduates are attracted to the city centre because of the concentration of knowledge-based jobs, which take up 50% of the jobs in the city centre

  • CBDs are confined areas associated with offices, administration and retail

  • Whereas other central areas include land uses such as residential and leisure

  • Nearly all cities have seen job growth

• Benefits of living in the city centre

  • Agglomeration and proximity: The ability to share knowledge and ideas, benefiting businesses and retail

  • Accessibility: Better shopping opportunities for low income groups whereas OOT retailers lack transport links, making them less accessible for lower income groups.

  • Highly qualified labour pools: Skilled workers are attracted to the skilled service companies located in city centres

Gentrification leads to highly educated professionals, yuppies and managerial workers replaced industrial workers. Older industrial buildings are renovated and converted into housing and businesses. E.g. New Islington, Manchester

• Growth and change of service economy

  • Out of Town retailing: large businesses in close proximity to one another in order to increase customer flow e.g. Intu Trafford Centre. Development in DIY industries e.g. IKEA. Usually located near major junctions for access.

  • City centre retailing: Regeneration of city centres e.g. The Corn Exchange, Manchester. Refurbishment of older buildings attracts customers to the area, benefitting the local economy.

  • Internet shopping: Growth of e-retailers, fewer expenses than physical store, open at all times, global location

  • Offices: Suburban clusters, conversion of old and abandoned buildings, science parks in close proximity to universities.

  • Leisure: Growth of leisure services such as multipurpose leisure facilities on CBD fringe and out of town, combined with retail developments

1.3.6 the 21st century knowledge economy and its social and economic impacts:

• Quaternary industry: Research and development and the knowledge economy including IT, education and the processes of information. Closely linked to the changing nature of communication and transportation system producing a set of townscapes and changing places.

• Multiplier effect: one new job in the digital, knowledge economy leads to five jobs elsewhere in the economy, this is known as the

• Quaternary cluster – Silicon Valley, CA

  • Developed from a fruit orchard to a global quaternary cluster due to a range of factors; Stanford university – encourages faculty and graduates to start businesses locally – e.g Larry Page and Sergey Brin, the creators of google – graduates given internships at existing companies – they go on to become entrepreneurs – entrepreneurs invest in products and services, provide employment opportunities – transport and communication improved, increase in globalization, international employees - skilled workforce remain in area – sustainable development

  • Clustering can lead to a range of positive effects e.g. Agglomeration and clustering allow easy transfer of ideas and career progression, high levels of highlight qualified posts for women, environmental awareness is widespread. Clustering can also have negative impacts e.g. Overloading of transport system, higher levels of pollution and congestion.

• Factors leading to the growth of Tech City, London

  • Amenities of an area which cater to the new workforce

  • Complementary firms cluster the area making use of converted warehouses

  • Branding and messaging that’ shade entrepreneurs and financiers aware of new activities

  • Cheaper rent for floor space than in CBD

  • Proximity to central London

  • Connectivity to London and UK

  • Higher broadband speeds

• Negative impacts of quaternary industry

  • Digital Exclusion: Lack of skills associated with computers together with poor access to broadband.

    • The reasons for lower use of digital technologies in excluded areas e.g. Northumberland, Anglesey may be due to an elderly population out-migration of young adults, a lack of training for older generations and a lack of jobs in the area which utilise technology.

1.3.7 the rebranding process and players in rural places

• Rurality = the degree to which an area of the natural, non-urban world depends on agriculture/food/forestry.

• Rural areas = Settlement with less than 10,000 people

• Sparse = a low dwelling density

• Peripherality = the distance from the opportunities provided by urban areas

The Rural Idyll

• Rural areas have been idyll-ised in many people’s representations. People tend to focus on rural natural landscapes that they wish to conserve, due inherent beauty/ ruggedness or because they live there.

Why has the primary workforce declined?

• Technological developments replace human labour e.g. technology and machinery for raising root crops replaced human labour.

• Rising scale of farms e.g. Supermarkets demand economies of scale, which has been especially evident in dairy farming

• Rise in factory farming e.g. livestock and birds as well as the picking, packaging and pricing within industrial units

• Year-round crops e.g. Demand of crops, such as Spanish tomatoes, in and out of season has increased supply from foreign (and usually cheaper) suppliers

Key words

• Urban renewal: A scheme to improve the condition of a town

• Redevelopment: A scheme that aims to stimulate growth in areas that have experienced decline

• Regeneration: Improvements to infrastructure, environment and society in an effort to stimulate growth in areas that have experienced decline

• Rebranding: Developing a place to reposition it's image and change people's view of it, helping to sell the place to a target audience

• Re-imaging: Positively changing the standing and reputation of a place through specific improvements

• Remaking: Restoring a location as it once was or as new

• Sustainability: Meeting the needs of today’s generation without compromising those of future generations

• Adaptation: changes that take place to react to a situation or condition. (They may or may not be successful)

• Thresholds: The minimum population required to sustain services

The consequences of rebranding on perceptions, actions and behaviour of people

• Rebranding can have a range of outcomes for and effects on people. Some people are attached to the memories of a past ‘golden age’, a process known as habituation or NIMBYism (Not In My Back Yard), with the consequence that they wish the village to remain as it once was (especially at the time when they moved to the village from urban areas, seeking the rural idyll). Very often, rebranding of a village seeks to play up past images.

  • Examples of areas that have undergone rural rebranding include The Eden Project, Glastonbury Festival and Shrewsbury

1.3.8 rural management and the challenges of continuity and change

• Processes of change affecting rural areas

  • Demographic: Age of population in rural areas is increasing as families, students and working age professional out-migrate to urban areas.

  • Counter urbanisation: The movement of people out of the city into surrounding villages and rural areas. The number of higher income groups seek affordable housing in rural areas has increased as a means to avoid congestion, pollution and multiple deprivation found in urban places.

  • Second home ownership: Buyers of second homes (holiday homes) removal property from the local market, leading to a lower population as first-time buyers are unable to purchase housing. This may lead to closing of local services as there is a lack of customers as the village is only popular during summer months.

• Challenges in rural areas

  • 1/3 of rural residents find public transport inadequate because of irregular services. Few shops are left in villages due to a reduction in threshold (not enough full-time residents), banks and schools are shut down. The permanent population is in decline, there is a loss of culture and traditional life as well as a lack of technology and communication.

  • Community Land Trusts are being used to counteract the pressure of counter-urbanisation and second homes. These schemes are set up by locals as they buy or are gifted the land which in turn they provides homes which are affordable creating opportunities to establish long-term steward of homes and assets.

• Effect on urban areas

  • People who leave the city tend to be qualified and skilled, leading to an untrained workforce to be left behind as they out-migrate. The population decline means the city loses out on local taxation revenue e.g. council tax, therefore fewer funds are available for the key facilities.

1.3.9 the rebranding process and players in urban places

• Reimaging and rebranding is sometimes called boosterism. This is when an area is promoted through the act of improving the perception of a place.

• Culture-led regeneration

  • The transformation and regeneration of places through cultural activity. It tends to be relevant for cities that have gone through big economic changes, place that may have lost their industrial base and have needed to reinvent themselves through cultural and art activity e.g. Museum of Photography, Film and TV (Bradford).

• Sports stadia

  • Stadia are frequently used as the catalyst for regeneration, although the trigger is often the result of the global pressure of hosting major sporting events

• Business Improvement Districts

  • Some regeneration strategies involve local authority government rebranding. An example of this is the Heart of Manchester BID 2013 – 2018. BIDs work to increase the attractiveness of the city centre to potential shoppers and visitors in order to provide a return on investment.

• Aims of the strategy:

  • Launch major new events in the city centre to attract footfall

  • Launch a city centre hosting scheme to improve the customer experience

  • Develop a stream of activity to boost midweek and evening trade

  • Deliver promotional campaigns and partnerships to attract more affluent shoppers

• Perspectives of groups about identity

  • Regeneration schemes may not usually consider all age cohorts and backgrounds during periods of change. A primary goal of regeneration is to develop local economies by catering to the needs of the affluent, those with disposable incomes and those that can access the changes. Certain generations and backgrounds may not benefit from these changes if they are not the target audience of the regeneration schemes. Age friendly cities aim to provide for the needs of all within the city.

1.3.10 urban management and the challenges of continuity and change

• Five C21st challenges for urban areas:

  • Rebalancing urban economies Satellite towns e.g. Bolton failed whereas reinvented capitals e.g. Cambridge thrived

  • Building new homes: There is a need for new homes often targeted towards “greyfield” land

  • Linking people and places: trams abolished, more efficient underground lines created. We, as a country, have not embraced the bicycle unlike Dutch cities

  • Living with finite resources: city inhabitants use 75% of planet’s natural resources

  • Fixing broken machinery: places more dependent on technology

• Overheating describes the rise in non-violent conflicts between groups as a result of increased demand of goods, services and space, leading to rising prices. Two main causes of overheating are new C21st employers and brownfield land.

• Problems of urban growth include:

  • The increased demand for housing leading to housing shortages and rapidly rising prices

  • Pressure to increase the number and spread of transport infrstruture

  • Brain drain e.g. professional and skilled workers are drawn to London

  • Rapid city growth may lead to congestion, unaffordable housing, low-wage residents being forced to relocate

• Segregation

  • A characteristic of cities in the USA is growing segregation, a feature which is becoming increasingly evident in British Cities also. This feature grows with city size.

    • Concentration: the increasing juxtaposition of similar social and racial groups

    • Invasion: the migration of similar groups into one area

    • Succession: the replacement of one group by another (e.g. Somalis replacing Afro-Caribbean)

    • Flight: often referred to a “white flight” due to former inhabitants leaving. 620,000 British people left London in 2011 when the population rose by 1 million

  • Segregation can be categorised by ethnicity, class, lifestyle, life cycle (people at similar points in their lives), linguistic, religious.

• Residential segregation may be the result of inequalities of income (rich-poor divide), limited housing, controlled purchasing (easier for people from affluent backgrounds to buy/ rent housing), social threats, marginalisation of workers, establishment of immigrant housing/ refugee communities, contrasting immigrant and racial groups, social policies which have led to divisions within urban areas usually as a result of rich-poor divide.

• Measures to reduce inequalities and spatial segregation are dependent on governmental polices which aim to address the increasing number of people living in poverty, create homes which are accessible for lower income workers and first time buyers, and reduce inequality.

Water and Carbon Cycles key facts:

2.1.1. Fixed amount of water (global) ~1385 million km3

Stores of water:

Oceans – 97% of total water on earth

Cryosphere – 2%

Groundwater store - <1% (can remain in store for 10,000 years)

Atmosphere - <0.01%

Evidence of natural global temperature variation:

• Cryogenian ice age (snowball earth) – 750 – 650 million years ago

• Palaeocene and early Eocene epochs (hothouse earth) – 65-35 million years ago

Explanation natural global temperature variation through (Milankovtich cycles)

• Eccentricity: Every 100,000 years, the Earth’s orbit changes from spherical to elliptical, changing the solar input.

• Tilt: The Earth’s axis is currently tilted at 23.5°, but this changes over 41,000-year cycle between 22° and 24.5°, also affecting solar input.

• Precession: The Earth’s axis wobbles, changing over 22,000 years, bringing further climate change.

2.1.2. Storage lengths of water stores:

• Soil water – 1-2 months

• Rivers – 2-6 months

• Seasonal snow cover – 2-6 months

• Glaciers – 20-100 years

• Lakes – 50-100 years

• Groundwater (shallow) - 100-200 years

• Groundwater (deep) – 10,000 years

2.1.3 Flashy hydrograph example: Upland Scotland

• Higher rates of orographic rainfall

• Steep topography reduces rates of infiltration

• Impermeable geology (granite) prevents percolation, leading to greater rates of overland flow

• Overgrazing of land reducing interception of rainfall

• Seasonal variation leads to snowmelt

Delayed hydrograph example: South East England

• Gentle topography allows for infiltration

• Permeable geology (chalk) allows percolation and groundwater flow

• Grassland vegetation intercepts rainfall, slowing movement towards rivers

2.1.4 Average cloud droplet size = 0.02mm

Average raindrop size = 2mm

2.1.5. 1976 UK drought

• High temperatures, lack of rain, jet stream was further north than usual  droughts

• Rationing of water supplies, crop failure, food prices rose

• Around 32’C in the UK for 15 consecutive days

• Parts of SW England received no rain for 45 days between July and August

• Following the drought, Sept- Oct experienced 30-70% more rain than average

2.1.6. 99.9% carbon stored in lithosphere

0.04% carbon stored in hydrosphere (second largest store)

2.1.7. Total volume of carbon stored in terrestrial biosphere ~ 3,000 GtC. Forests are significant carbon stores; they make up more than half of all terrestrial ecosystem storage.

TRF carbon storage:

• 550 GtC in biomass and soil

• ~100 tonnes per hectare of carbon stored in soil

Temperate grassland

• 180 GtC in biomass and soil

• ~100-200 tonnes per hectare of carbon stored in soil

2.1.8 50% of organic matter in peat is carbon based

Globally, peatland stores ~550 billion tonnes of carbon. Peatland stores double the amount of carbon that is stored in all the world’s forests

2.1.9 and 2.1.10

CO2 emissions: Increased from 280ppm to 406ppm in from 1750 to 2017

Fossil fuels: 2014 – 2016, 36 billion tonnes of carbon emissions per year

Global mean surface temp: In 2015, increase in 0.87°C since 1950s

Extreme weather: £3bn damages because of intense rainfall (2017), droughts in Central America

Sea level rise: Total global average sea level rise 200mm since 1900 (eustatic)

Ocean acidification: Since 1750, the pH has dropped by 0.1 (30% change)

Photosynthesis: Globally, flora sequesters 100GtC per year

Deforestation: Since 2005, the Earth’s total forest area continued to decreased by approx. 13 million hectares per year

Radiation: 31% of short wave radiation is reflected away by clouds and gases in the atmosphere

Natural variation in temp: Milankovitch cycles e.g. change in orbit shape

2.1.1 the concepts of systems and mass balance

• Globally, there is a fixed volume of water on Earth – this is known as mass balance

• Stores: Where water is held in the system

• Input: Water entering the system i.e. Precipitation

• Outputs: Flows leaving the system for example, evaporation of ocean water

• Flows are movements (or transfers or fluxes) between stores in a system

• The global water system is closed – water cannot be lost from the system

• The whole Earth system can be broken down into smaller subsystems:

  • Atmosphhere- the layer of gas between the earths surface and space, held in place by gravity

  • Biosphere- all living organisms found on earth eg plants, animal, birds, fungi, insects, bacteria

  • Hydrosphere- all of the water on earth that may be solid/liquid/gas

  • Lithosphere- the outermost part of the earth. It includes the crust and upper parts of the mantle

  • Cryosphere- all of the areas of the earth where water is present as snow or ice eg ice sheets, ice caps, alpine glaciers, sea ice and permafrost

• The relative sizes of the global stores will vary as a result of temporal and spatial changes

• Short term: ice accumulation & ablation, seasonal variation, long term climate change

• ‘Snowball Earth’ - Cryogenian ice ages, 750-650 million years ago.

• ‘Hothouse Earth’ - Palaeocene and early Eocene epochs (about 65-35 million years ago)

• These changes occurred because of long-term natural processes, including three cycles affecting the Earth’s orbit around the sun, which bring warming and cooling over long period of time (as incoming levels of solar radiation change).

  • Every 100,000 years, Earth’s orbit changes from spherical to elliptical, changing solar input.

  • The Earth’s axis is currently tilted at 23.5°, but this changes over 41,000-year cycle between 22° and 24.5°, also affecting solar input.

  • The Earth’s axis wobbles, changing over 22,000 years, bringing further climate change.

    • These orbital cycles are termed the Milankovitch cycles.

2.1.2 catchment hydrology- the drainage basin as a system

• The global water system is closed – water cannot be lost from the system whereas the drainage basin is an open system as allows water can enter and leave.

• Input: Water entering the system

  • Precipitation is any product of the condensation of atmospheric water vapor that falls under gravity.

• Flow: The movement of water between components

  • Rainwater dripping from leaves and branches towards the ground is called throughfall

  • Water which flows to the ground via vegetation stems and trunks is stemflow

  • Infiltration is the movement of water from the ground surface into the soil

  • Throughflow is the movement of water laterally (sideways) through the soil, via (1) a matrix of pore spaces, fissures and (2) pipes (animal burrows)

  • Percolation is the transfer of water from the soil into the underlying bedrock

  • Groundwater flow is the vertical and lateral movement of water through a drainage basin’s underlying rock due to gravity and pressure

  • Overland flow is the movement of a sheet of water across the ground

  • Infiltration-excess overland flow occurs when rainfall intensity is so great that not all water can infiltrate, irrespective of how dry or wet the soil is

  • Saturation-excess overland flow happens if rainfall continues for a long time. The entire soil becomes saturated; overland flow begins

  • Channel flow is the movement of water through streams, rivers and other channels

• Store: When water is held within the system

  • Interception - leaf and plant surfaces

  • Vegetation store - water held in the biomass itself

  • Surface store - water collected on the ground in depressions and hollows, and also snow cover

  • Soil moisture store - water held in soil pores space

  • Channel store - water held in the river channel itself

  • Groundwater store - water stored in solid rock and in any superficial deposits e.g. Gravels below the soil

• Output: Water leaving the system

  • Channel discharge is the water leaving a drainage basin via its main river during a unit of time

  • Evaporation is the change in state of water from a liquid to a gas. Meteorological factors influence the rate of evaporation (temperature and wind speed)

  • Transpiration is the diffusion of water from vegetation into the atmosphere. Water vapour is lost through the stomata (pores) of leaves

2.1.3 temporal variations in river discharge

• River regime: the annual variations in the pattern of flow or discharge of a river, measured at a particular point

• Discharge: the volume of water (m³/s) passing a given point

• Simple regime: A river regime based on one river with a single peak in the year

• Complex regime: A river regime based on a river with lots of tributaries which flow through a variety of climates and environments

• Lowland areas with high vegetation density and permeable geology will have lower river flow levels and a delayed peak whereas upland areas with impermeable geology leads to steeper peaks and river flow levels

• Storm hydrographs

  • Peak discharge: Maximum rate of flow during a storm event

  • Peak rainfall: Maximum rainfall recorded

  • Rising limb: When discharge beings to rise

  • Lag time: Time different between peaks of rainfall and discharge

  • Falling limb: When discharge begins to fall

  • Preceding discharge: Rate of flow prior to latest storm event

  • Bankfull discharge: Maximum discharge before flooding occurs

  • Base flow: Normal minimum flow of the river

• Factors affecting storm hydrographs

  • Antecedent conditions (weather and soil moisture conditions immediately prior to a storm event). Saturated soil → rapid overland flow → flashy hydrograph

  • Seasonal effects: High intensity winter rainfall + saturated soil + cold temperature (minimal evaporation and transpiration outputs) → flashy hydrograph

  • Precipitation: snow is stored on ground for longer than rainfall → delayed peak discharge.

  • Vegetation: Greater vegetation density → higher levels of interception, storage and evapotranspiration; this reduces rainfall and increase the lag time

  • Rock type: Permeable rock → greater percolation & ground storage, leaving less run off

  • Soil depth: Deeper soil stores more water and results in less run off

  • Soil type: variation in soils affect how much infiltration and throughflow can occur e.g. clay soil → low infiltration rates

  • • Agriculture and land use: Grassland → interception, stemflow and well aerated soils

  • • Drainage basin: Circular drainage basin → quick access to river → flashy hydrograph

  • • Drainage density: Total length of streams (km) in relation to total drainage basin area (km2). Low drainage density → longer lag time and a reduced risk of flooding

  • • Slope angle: Steeper slopes → less infiltration and increased run off

2.1.4 precipitation and excess runoff within the water cycle

• Water vapour needs to form around condensation nuclei (around small dust or sea salt particles

• Increased temperature → air uplift → pressure falls with altitude → air expands → fewer air collisions → fall in temperature → clouds form at saturation point

• Convectional rainfall: Earth’s surface warms → heats air above (conduction) → heated air rises, expands, cools → continues → condensation → rain

• Frontal rainfall: Two surface air streams meet → warmer air rises over colder low-pressure air → heated air rises, expands, cools → continues → condensation → rain

• Orographic rainfall: Air forced to rise over barrier → cools → condensation → rain. Leeward slope is within a rain shadow (very little rain occurs here)

• Feeder-seeder mechanism: water droplets fall from higher altitude clouds and join lower level orographic clouds, collecting water, leading to heavier rain

• Theories of precipitation formation

  • Not all clouds produce rain. An average rain droplet is 1 million times larger than a cloud droplet.

  • Bergeron-Findeisen process: Clouds at high altitude contain a mixture of water droplets and ice crystals. Ice crystals grow rapidly by attracting vapour from the water droplets. Eventually, the ice crystals become too large to be held aloft; in falling to the ground, they pass through warmer air and melt to produce rain

  • Collision process: ‘Super-sized’ condensation nuclei, e.g. large sea salt particles, provide ‘seeds’ around which very large water droplets form. The larger ‘super’ droplets fall and collide with smaller droplets, absorbing them.

• Causes of excess run off generation

  • Runoff: All rainwater following rainfall event that leads to river discharge (overland flow, through flow, groundwater flow)

  • Snowmelt & ice ablation: increased run off for rivers fed by glaciers

  • Storm activity: Intensive precipitation → saturation excess → overland flow

  • Storm activity: Prolonged precipitation → infiltration excess → overland flow

  • Monsoon season: Torrential and widespread rainfall e.g. South East Asia

  • Urbanisation: More impermeable surfaces reduce rates of infiltration, throughflow and soil storage. Sewer and drainage system transport water faster to the river. Less vegetation reduces transpiration and interception

  • Deforestation

2.1.5 Deficit within the water cycle:

• The balance between precipitation, evapotranspiration and runoff is known as the water balance:

  • P = Q + ET + ΔS

• Precipitation = discharge + evapotranspiration + change in water storage

• If precipitation is lower than the combined loss of water due to evapotranspiration and run off, a water deficit is created.

• Jan – Apr: High precipitation rates during winter season → soil moisture surplus

• May – July: Increased temperature during summer → soil moisture deficit (plants use water)

• Oct – Dec: Less intensive sun → precipitation rates > evaporation rates → soil moisture recharge

• Drought conditions

  • Meteorological: Extended period of low or absent rainfall relative to the average for a region.

  • Agricultural: when there is insufficient moisture for average crop production

  • Hydrological: when available water reserves (in lakes, reservoir and aquifers) fall below acceptable levels. This condition can arise even when there have been recent rains.

• Human causes of deficit in the water cycle

  • Causes: Aquifer depletion and over extraction of surface water resources

  • Agricultural demands: Largest user of water. Used for crop cultivation, processing, irrigation and food distribution

  • Industry: Second largest user of water. NICs and increase in industrial activity, increasing water consumption

  • Household water consumption: Population growth and poverty reduction is leading to increased demand and use of water. Greater water consumption in areas of water shortages e.g. Middle East may cause further problems

  • Aquifer: Permeable rock layer e.g. chalk New Red Sandstone which contains water that can be extracted. Aquifers can restore naturally via percolating rainwater. Over extraction can lead to weakening of rock structure. Building above aquifers compacts pore size leading to permanent loss of water storage capacity.

  • Artisan aquifer: Aquifer forms between impermeable rock layers within syncline structure of sedimentary rock

  • Aral Sea (Kazakhstan & Uzbekistan) has shrunk to 10% of its original size as a result of mismanagement e.g. large volumes of fruit and cotton irrigation

2.1.6 the global carbon cycle:

• The carbon cycle is the biogeochemical movement of carbon from one part of the global system to another. These changes can be local (forests) or global (atmosphere).

  • Atmosphere-0.001% of earths carbon is stored ad CO2 and CH4

  • Biosphere- 0.004% of all carbon is stored in living organisms, when living organisms die they decay and transfer carbon to the soil

  • Hydrosphere- the second largest carbon store on earth, containing 0.04%- CO2 dissolved in lakes, rivers and oceans

  • Lithosphere-99.9% of carbon on earth is stored here. 0.0004% of earths carbon is stored in fossil fuels. Carbon can be found in sedimentary rocks eg limestone

  • Cryosphere- contains less than 0.01% of earths carbon, stored in permafrost or decomposed flora and fauna frozen into the ground

• Stores: Carbon held in a particular part of the global system e.g. 2,300 gigatonnes of carbon are stored in soil and peat worldwide.

• Carbon sink: A store that absorbs more carbon than it releases

• Carbon sources: Store that releases more than it absorbs

• Flows: Transfers of carbon between stores e.g. volcanic activity adds 0.1 gigatonnes of carbon to the atmosphere every year.

• Processes: Physical mechanisms that drive carbon movement within the carbon cycle e.g. photosynthesis

• Mass balance: At a global scale, the total amount of carbon is conserved over time.

• Carbon sequestration: Natural capture and storage of CO2 from the atmosphere

• Carbon pathways and processes – Land and atmosphere

  • Photosynthesis- plants and phytoplankton ‘fix’ carbon gas as carbohydrates

  • Respiration- CO2release back into atmosphere. Plants create energy for respiration through the breakdown of stored glucose

  • Decomposition- dead matter breaks down through physical (wind and water), chemical (leech and oxidation) and biological (feeding and digestion) mechanisms

• Carbon pathways and processes – Ocean and atmosphere

  • The movement between ocean and atmosphere is achieved through carbon pumps mechanisms

  • • Physical/ inorganic pump: CO2 dissolves from the atmosphere to the ocean surface, and diffuses into the colder, denser waters. Downwelling carries the carbon molecules into the deep ocean.

  • • Biological/ organic pump: Phytoplankton living within the surface layer (euphotic zone) photosynthesise. Phytoplankton are consumed by other organisms, transferring carbon within the food web

  • • Carbonate pump: Coccolithophores (specialised form of phytoplankton) produce Calcium Carbonate shells from Carbonic acid (CO2 reacting with water).

  • • Colder, higher pressure waters hold more carbon therefore increasing global temperatures results in more CO2 being released from Earth’s oceans

• Carbon pathways and processes- land and ocean

  • Carbonation- weathering of limestone allows dissolved CO2 to be transported through rivers to the ocean

  • Dissolved CO2 is used by organisms to create carbonate shells → deposited on ocean floor → lithification

  • Carbon stored in rock is released through volcanic activity

2.1.7. Carbon stores in different biomes

• The total amount of carbon stored in the terrestrial biosphere is approximately 3,000 GtC. This storage is spread unevenly among the different terrestrial biomes. Forests are significant carbon stores; they make up more than half of all terrestrial ecosystem storage.

  • Ecosystem: A community of plants and animals whose lives are closely linked to each other and the climate and soil of the area in which they grow or live.

  • Biome: A large naturally occurring community of flora and fauna occupying a major habitat, e.g. forest or tundra. An ecosystem on a global scale.

Differences in carbon storage and flows between Tropical Rainforest & Temperate Grassland biomes:

• Anthropogenic impacts on biome carbon stores

  • Deforestation: Removal of trees for trade, industry, urbanisation and creating commercial agricultural land e.g. oil palm cultivation. Deforestation reduces biosphere carbon storage e.g. Soya crop cover = 2.7 tonnes per hectare whereas rainforest store = 180 tonnes per hectare.

  • Afforestation: Planting of trees especially in areas which have never been forested or experienced deforestation. The UN’s Reducing Emissions from Deforestation and forest Degradation (REDD) scheme provides incentive to produce LICs & NICs to conserve rainforest by placing a monetary value on forest conservation. Monoculture (planting of single species) leads to greater carbon storage if replacing smaller biome e.g. grassland.

  • Agriculture: The removal of natural forest cover and soil erosion from over farming reduces carbon storage. The use of manure, plant debris, composts and crop rotation can increase overall soil carbon.

2.1.8 changing carbon stores in peatlands over time

• Peat accumulation and carbon storage

  • Peat: Thick layer of black/dark brown sticky and wet soil material containing very high levels of partially decomposed vegetation (mosses, rushes, sedges and bracken).

  • The carbon-rich plant remains are slowly compressed as more material is added each year

  • Decomposition is prevented because of a waterlogged environment, creating an anaerobic condition

  • Peatland is found in upland areas e.g. Northern Scotland that experience high rates of precipitation. When plants die, they accumulate within the soil. The upland areas experience orographic rainfall which creates waterlogged environments. This causes the rate of decomposition to be reduced because of anaerobic conditions. Further decomposition is reduced due to colder temperatures. This means less carbon is lost to the atmosphere as CO2. This is because the rate at which atmospheric carbon is fixed in new peatland plants by photosynthesis greatly exceeds the rate of loss of carbon from decomposition.

  • 3% of Earth’s land surface (4 million km2) is covered by peat

  • Some peat soils in tropic areas are composed of rainforest remains e.g. Indonesia. 60 billion tonnes of carbon is stored here, with peat reaching depths of 15m.

• Peat extraction and drainage

  • Drainage, burning, cultivation and extraction of peatland releases 2 billion tonnes of CO2 into the atmosphere per year. This makes up 10% of anthropogenic global emissions.

  • Only 20% of UK peatlands are not degraded and remain in a pristine state

  • Rates of carbon sequestration in degraded peatlands are reduced; they may even become sources of carbon emissions instead

  • Peat has been dried and burned traditionally in many rural areas as a fuel source

  • Peat is extracted for use in garden centres, and food and drink industries (smoked food and whiskey)

• Peat management and carbon store restoration

  • Two examples are the re-establishment of a plant cover e.g. sphagnum mosses and ‘rewetting’ of drained peatlands by raising and stabilising the local water table → CO2 emissions from decomp. being reduced immediately. Also creates anaerobic conditions → encourages peat development → carbon sequestration → area restored as carbon sink

2.1.9 links between the water and carbon cycles

• Energy budget: The state of balance between incoming solar radiation and the re-radiated heat or reflected energy

• Desertification: Is the process by which land becomes drier and degraded as a result of climate change or human activity

Links between Water and Carbon cycles at a local scale

How desertification in LICs is driven by climate change, land use and change in processes

• Links between Water and Carbon cycles at a small extent

  • Precipitation saturates the leaf litter and can speed up the rate of decomposition. The impact of rain droplets may be sufficient to help material fragment. By keeping the soil below the litter moist, precipitation also encourages earthworm activity

  • Overland flow could play an important role, physically washing large amount of litter or decomposing organic matter into streams or sewers in urban areas.

  • Humus that remains on site in the soil can store water. Humus can hold the equivalent of 80-90% of its weight in moisture, and therefore increases the soil’s capacity to withstand drought conditions

2.1.10 feedback in and between the water and carbon cycles

• Equilibrium: A state of balance between flows and processes

• Equilibriums in coasts (e.g. sediment cells), water cycle (e.g. water balance P = Q + ET + ΔS), carbon cycle (e.g. solar radiation input and output from Earth)

• System feedback: How a system reacts to a change

• The two forms of feedback: Positive and negative

• Positive: Amplifies the change in input/output (e.g. build up of beach slows down waves → constructive → build beach)

• Negative: Mitigates the change in inputs/outputs (e.g. Beach is eroded → cliff behind becomes exposed and eroded → Eroded material forms beach)

• Threshold: The system limit/ ‘point of no return’. Any change beyond this may be irreversible e.g. WC/CC: Desertification → damaged soils → cannot sustain plant life

• Examples of feedback loops

  • Cryosphere positive feedback: Ice has an albedo of 80%, reflecting 4⁄5 of all incoming solar radiation. Melting ice reveals darker waters (which has a lower albedo) and can absorb more heat. This leads to greater rates of ice ablation, exposing more darker waters. Warming waters also heats air above it → rising atmospheric temperature.

  • Cryosphere negative feedback: Melting ice reveals darker waters → increased temperatures → greater rates of evaporation → more cloud cover → light coloured cloud reflects solar radiation → water absorbs less heat

  • Methane positive feedback: Rising global temperatures is causing methane stored in permafrost to be released → increase in GHGs causes back radiation → heating atmosphere temperatures → melting more permafrost

  • Terrestrial and marine carbon feedback: Rising global temperatures → increased evaporation rates → increase in GHGs causes back radiation → heating atmospheric temperatures. However this may lead to more cloud formation, reflecting solar radiation.

  • Marine carbon feedback (physical pump): Rising global temperatures → heat oceans → reducing water’s ability to absorb CO2. May lead to oceans releasing CO2 into the atmosphere (positive feedback)

  • Marine carbon feedback (ecosystem): Ocean acidification may damage the health of ocean flora and fauna → reducing biological sequestration of CO2 (positive feedback)

  • Terrestrial carbon feedback: The location of the tree line may move north → increasing the size of coniferous tree biomes → increasing carbon store (negative feedback)

• Implications of system feedback for life on Earth

  • The GMST rise prediction for a high emissions scenario varies from 3°C to 5°C

  • Although the reduction in cryosphere will increase meltwater in the short term, in the long term it could lead to dangerous water shortages because there will be very little ice left to melt.