GCSE Geography - ALL OF TOPICS -

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Tectonic Plates

  • We live on the earth's crust, it's only 20km thick
  • At the centre of the earth, there is a core made of solid nickel and iron
  • around the core is the mantle which is the semi-molten rock which moves slowly
  • the crust is divided into tectonic plates, 2 types
  • oceanic- thinner and denser (5km thick)
  • continental- thicker and less dense
  • the plates are moving because the rock underneath the mantle is moving due to convection currents
  • the places where plates meet are called plate boundaries
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Plate Margins

  • Destructive plate margin
  • push together- moving together
  • denser oceanic crust sinks below the lighter continental crust
  • oceanic crust sinks into the magma in the mantle where it melts in the subduction zone
  • energy builds up, can be released as an earthquake
  • or the molten magma rises up causing a volcanic eruption- composite cones
  • the continental crust becomes crumpled into fold mountains or ocean trenches
  • Constructive Plate Margin
  • Moving in opposite directions- apart
  • mostly happens under oceans
  • plates move apart and the gap is filled by magma rising from the mantle which cools creating a new crust, shield volcanoes and volcano islands
  • moving past each other (sideways)
  • Conservative Plate Margin
  • move in the same direction
  • or if one moving slightly faster, pressure builds up along the fault line until one plate jerks past the other which causes an earthquake
  • e.g. along the west coast of USA
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Landforms at Plate Margins

Fold Mountains                                                                                                                 They lie on a collision zone and the two continental plates are pushing against each other. As they are the same density neither sink, so they push upwards forming fold mountains

Ocean Trenches                                                                                                          

Ocean trenches are also found on destructive plate margins as the denser plate sinks below the continental plate it creates a deep-sea trench

Composite Volcanoes                                                                                                     Found at destructive plate margins, when the oceanic plate sinks into the mantle and melts with the seawater, then rises up through the cracks in the earth's crust forming volcanoes. Eruptions are violent, they are also layered of ash and lava with a tall cone shape

Shield Volcanoes

Found at constructive plate margins as the plates move apart the magma rises up from the mantle, these are non-violent eruptions and have a wide base and gently sloping sides

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Formation Of Fold Mountain

Where an area of sea separates two plates, sediments settle on the sea floor in depressions called geosynclines. These sediments gradually become compressed into sedimentary rock.

When the two plates move towards each other again, the layers of sedimentary rock on the sea floor become crumpled and folded.

Eventually the sedimentary rock appears above sea level as a range of fold mountains.

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Problems with Fold Mountain

Relief: high and steep

  • mountain valleys= narrow and gorge like
  • little flat land for forming settlements

climate:, increasing height becomes colder, windier, wetter and more snow

  • short growing season
  • often impossible to grow crops at such high levels

soils- stoney, thin and infertile

Accessibility, roads and railways= expensive and difficult to build

  • travel disrupted by frequent rock falls, avalanches and bad weather
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Uses of moutain folds

Farming: higher mountain slopes aren't good for growing crops so used for grazing animals like mountain goats

  • lower slopes used for growing crops, steeper slopes sometimes terraced to make easier

Mining: major source of metal ores

  • steep slopes make access difficult so zig-zag roads have to be carved out the sides of the mountain

Tourism: spectacular scenery which attracts tourists, winter- skiing, snowboarding, summer- walkers

  • tunnels have been cut through fold mountains to make straight fast roads improving communications

Hydro-electric power- steep sided slopes and high lakes makes them ideal

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Volcanoes

  • found at destructive and constructive plate margins
  • a volcano= cone shaped mountain formed by surface eruptions from magma chamber
  • At destructive margins
  • The oceanic trench moves down into the mantle, where its melted and destroyed
  • a pool of magma forms
  • the magma rises through cracks in the crust called vents
  • the magma erupts onto the surface (lava) forming a volcano
  • At constructive margins
    magma rises up into the gap created by the plates moving apart
  • The worlds distribution of volcanoes shows almost perfect fit with tectonic plate margins
  • each time there is a volcanic eruption a new layer of lava is added to the surface of the volcano
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Types of Volcanoes

Composite volcanoes- e.g.

  • lava is usually thick and flows slowly it hardens quickly forming a steep-sided symmetrical volcano
  • made up of ash and lava in alternate layers, the lava cools inside and next eruption there will be an explosion
  • subsidiary cones and vents form

  Shield Volcano- eg

  • lava is runny and flows quickly and spreads over a wide area forming a low, flat volcano, made only of lava, frequent non-violent eruptions
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Super volcanoes

A supervolcano is much bigger than a standard volcano, the erupt with massive volumes of material and develop over hotspots e.g. yellowstone national park

How?

  • magma rises through cracks in the crust forming large magma basin below the surface, the pressure of the magma causes a circular bulge on the surface
  • the bulge cracks creating vents for lava to escape through, lava erupts out of vents causing earthquakes and sending up gigantic plumes of ash and rock
  • as the magma basin empties the bulge is no longer supported so collapses
  • when the eruption finishes there is a big crater (caldera) left where the bulge collapsed, sometimes these get filled with water to form a large lake e.g. Lake Toba in Indonesia

characteristics: flat, cover a large area, have caldera

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concequence

Last known eruption about 75,000 years ago

  • so much dust would circulate in the atmosphere it could lead to a 'volcanic winter' which would lower global temperatures because less sunlight would reach the surface- mini ice age
  • a thick cloud of super-heated gas and ash would flow at high speed from the volcano, killing, burying and burning everything it touches
  • releases a lot more material

 

  • Mount St Helens in the USA in 1970 released 1km  (cubed) of material but if a supervolcano erupted it would alter the landscape of hundreds if not thousands of kilometres
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Volcanoes- Negative effecs

primary effects- immediate impact

  • people die/injured
  • houses/buildings/businesses/ farmland destroyed
  • communications disrupted/destroyed
  • public services disrupted

Secondary Effects-

  • healthcare not able to access- more people die
  • loss of income/homeless/ no food- more die
  • economic problems- the cost of rebuilding
  • grief- family stress
  • water contamination- disease and death
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Volcanoes- Posative effecs

fertile soil, tourism (hot springs)

industry (minerals- sulphur, borax, pumice),

generating power and heating things (geothermal power)

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Warnings of a Volcanic eruption

  • Small earthquakes
  • increased emissions of steam and gases
  • visual signs of bulging around the crater
  • in more developed countries there are special machines that give advanced warnings
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Volcano (LEDC)- CASE STUDY - Montserrat

The Soufriere hills Montserrat

  • the main eruption 25th June 1997, started in July 1995
  • 4-5 million m3 of rocks and gas release
  • 19-23 people killed

Cause:

  • above a destructive plate margin where the Atlantic plate is being forced under the Caribbean plate
  • magma rose up at weak points under the Soufriere hills forming an underground pool of magma
  • the rock above pool collapsed, opening the vent and causing an eruption
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Volcano (LEDC)- CASE STUDY - Montserrat Timeline

July 1995- first eruption- signs of volcanic activity

August 1995- 50% population evacuated

1996- finally erupted-mudflows then pyroclastic flows, part of dome collapsed

April 1996- eruption continues

June 1997- eruption killed 23 people and lava became more explosive

Few months laterPlymouth burned to ground and covered with ash

Only 39/103 square kilometres were considered safe

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Volcano (LEDC)- CASE STUDY - Montserrat

Montserrat located in the Caribbean Islands                                                                         This volcano is on a destructive plate margin meaning the oceanic plate sunk and was melted       and the magma raised leading to a violent eruption

The effects

More than half of Montserrat became uninhabitable, infrastructure was destroyed including the airport, 19 people died and many people fled from the Island and tourism decreased

Immediate response

Residents evacuated, the population fell to 3500, the British government spent money on aid - temporary buildings, charities set up temporary schools and sent emergency food for farm animals

Long term responses

People returned to the island as the population raised to 5000, the population structure changed as many young people left and didn't return and the British government spent £200 million to restore electricity, water and build infrastructure

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Earthquake

Earthquake= vibrations in the earth's crust which shake the ground surface- some too small to feel

happen on all 3 plate margins

  • destructive- tension builds up when one plate gets stuck as its moving down past the other into the mantle
  • constructive- tension builds along cracks within the plates as they move away
  • conservative- tension builds up when plates are grinding past each other get stuck

Pattern= around tectonic plates

  • lots around west side of south American plate
  • lots around Philippine plate
  • on African plate marks out practically the whole marginEarthquake= vibrations in the earth's crust which shake the ground surface- some too small to feel

    happen on all 3 plate margins

    • destructive- tension builds up when one plate gets stuck as its moving down past the other into the mantle
    • constructive- tension builds along cracks within the plates as they move away
    • conservative- tension builds up when plates are grinding past each other get stuck

    Pattern= around tectonic plates

    • lots around west side of south American plate
    • lots around Philippine plate
    • on African plate marks out practically the whole margin
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The Richter Scale

  • Measures magnitude (energy released) of an earthquake
  • measured using a seismograph
  • doesn't have an upper limit (normally between 1-10)
  • it's logarithmic- means that an earthquake with a magnitude of 5 is 10 times more powerful than one with a magnitude of 4
  • most people don't feel earthquakes of magnitude 1-2
  • major earthquakes are above
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The Mercalli Scale

Used to indicate intensity/effects of an earthquake

effects are measured by asking eyewitnesses of what happened and takes into account effects on Earth's surface, people and buildings

given a number between 1-12, sometimes Roman numerals

I (1)- rarely felt by humans

II-IV (2-4)- feeble to moderate effects- felt by people indoors

V-VII (5-7) strong effects, causing panic felt by everyone, structural damage

VIII (8) destructive to poorly built structures only slight damage to those well designed

IX-XII (9-12) ruinous, disastrous, total destruction

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Why Earthquakes Happen

90% occur where plates are colliding

focus= point at which the earthquake originates- waves stronger and do more damage

Epicentre= the point on the surface directly above the focus where the greatest force of the earthquake is felt

Shock-waves= radiate out in all directions gradually becoming less strong as you get further away from the epicentre

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Effects If Earthquakes

collapsing buildings, bridges and roads- people are killed by being trapped

the severity of primary effects depends on human and physical factors

chance effect- time of day-

were fewer people closer to epicentre?

Fires- caused by fractured gas pipes, bringing down electricity cables- spread quickly in areas of poor quality housing

Tsunamis- giant sea wave- really dangerous in areas of low lying coasts

landslides- most likely on steep slopes and in areas of weak rock

disease- typhoid and cholera spread easily when pipes burst- leads to a shortage of water and contamination

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Waves

How waves are formed

Out at sea, the wind tugs at the surface of the water, causing the wave shape to move, when the wave moves into shallow water near the coast it is distorted until it 'breaks' then the water moves forward, water rushing up the beach is called the swash and when the water drains back down the beach is called the backwash

Size of a wave

How strong the wind is

How long it blows for

How far it travels

The distance the wind blows over is called a fetch

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Wave Type

Destructive waves

The waves have a weak swash and a strong backwash pulling sand and pebbles back down the beach. These are destructive because they remove material from the beach. The characteristics of these waves are steep, high waves that are close together and crash down onto the beach.

Constructive waves

The waves have a very strong swash and a weak backwash as they push sand and pebbles up the beach and leave them behind when the water retreats because the wave isn't strong enough to remove them. They are low waves with gaps between them.

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Coastal Erosion

Hydraulic Action - Water forced into the cracks in the rock, compressing the air inside so when the wave retreats, the compressed air blasts out and can force the rock apart.

Abrasion - Loose rocks are thrown against the cliff by the waves and wears the cliff away and chips rock off

Attrition - Loose sediment knocked off the cliff by hydraulic action and abrasion is swirled around by the waves and collides with other sediment leading to the sediment getting smaller and smaller

Solution - When seawater dissolves material from the rock, it happens along limestone coasts where calcium carbonate is dissolved

Landforms by erosion

Wave-cut notch - Waves hit the bottom of the cliff, eroding a wave-cut notch. The cliff above the notch is undercut and the overhanging rock eventually falls, leaving the steep cliff face.

Wave-cut platform - As the cliff errodes, it leaves behind flat rocks and rock pools.

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Coastal Erosion

Headlands and bays

Where coasts are formed from alternating bands of hard and soft rock. The less-resistant rock will form bays. The more-resistant rock will form headlands.

Caves, arches and stacks

A joint or fault in resistant rock appears abrasion and hydraulic action widen the joint to form a cave. Waves make the cave larger until it cuts through the headland to form an arch which is eroded so the roof collapses as it becomes too heavy. This leaves a tall stack which is eroded and collapses, leaving a stump

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Coastal Transport

Methods of transport

Suspension - Fine sediment is carried as a suspension in the water making it look muddy or murky

Solution - Dissolved material is carried along in solution, so you can't see it

Traction - Larger pebbles and cobbles are rolled along the sea bed

Saltation - Small pebbles are moved when one pebble hits another, causing it to bounce. The bouncing can cause a chain reaction

 Longshore drift          

 Waves approach the beach at a slight angle, as the waves break, the swash carries material  up the beach at the same angle as the wave approached, as the swash dies away the backwash and any material carried by it falls straight back down the beach under the influence of gravity meaning the material has moved along the beach in a zig-zag route. To prevent longshore drift we build wooden or rock fences called groynes to trap the sediment and stop the transportation along the coast

Coastal Deposition

Spits

Spits are long narrow ridges of sand and shingle stretching out from the coast. They form where longshore drift moves sediment along the coast in the direction of the prevailing wind. When the coastline changes direction, such as at the mouth of a river, the sediment is then deposited as a long ridge, which streches away from the coast to form a spit

Bars

Bars are narrow ridges of sand and shingle that grow across a bay as a result of longshore drift. They can trap lagoons behind them. The lagoon may fill up with sediment eventually. Sometimes storm waves sometimes crash over the top or break through a bar. 

Collapsing Cliffs

Why do cliffs collapse?

Marine processes - The base of the cliff is eroded by hydraulic action and abrasion making the cliff face steeper

Sub-aerial processes - The cliffs are attacked by weathering, loosening the rocks causing them to fall or slide because of gravity

Types of weathering

Mechanical weathering - (Freeze-thaw) When temperatures drop below freezing at night and rise during the day, so the water in the cracks freeze and expands then thaws again which repeats again and again until the rock is weakened and fragments break away

Chemical weathering - (Solution) When water reacts with the calcium carbonate in the rocks e.g. limestone so the calcium carbonate dissolves and is washed away in solution, weakening the rock

Mass Movement

Sliding

When large chunks of rock slide down the slope quickly without any warning, making it very dangerous to walk along the bach under the cliffs

Slumping

Where cliffs are made of clay, the clay becomes saturated during heavy rainfall and oozes down towards the sea as part of a mud or debris flow

Human actions making it worse

Builiding on top of unstable cliffs can put pressure and weight on them adding to the chances of cliff collapse

Cliff Collapse - Holderness Coast

One of the fastest eroding coastlines in Europe

1.8m of land is lost every year e.g. Great Cowden

Reasons for rapid erosion

Easily eroded rock type - the cliffs are made up of clay so its likely to slump

Naturally narrow beaches - beaches slow waves down reducing their power but narrow beaches give less protection

People worsening the situation - groynes have been built at mappleton which stop the material being moved down the coast, so some of the coast having no sediment to protect the cliff face

Powerful waves - Holderness faces the prevailing wind which brings waves from the north east (across the arctic ocean) which is a large distance so the waves gain more power so the coast is battered by highly erosive waves

Cliff Collapse - Holderness Coast 2

Impacts on lives

Homes near cliffs e.g. Skipsea are at risk of collapsing into the sea

Property prices have fallen sharply along the coast as the houses are at risk

Some settlements are not accessible because roads have collapsed into the sea

Businesses are at risk and people will lose their jobs e.g. seaside caravan park looses 10 pitches a year

The gas terminal at Easington is at risk as its near the cliff edge, this terminal powers 25% of Britain's gas supply

80,000m of farmland is lost each year, having a large effect on farmers lives

Environment impacts - the lagoons near Easington are part of the SSSIs (Sites of Special Scientific Interest) If the bar erodes it will connect the lagoon to the sea, destroying it

Rising Sea Levels - Maldives

A small island located in the Indian Ocean with the highest point of the land being 2.4m above sea. Tourism provides 30% of the Maldives GDP

What is happening?

Sea levels are rising and islands in the Pacific Ocean are beginning to disappear. Why? Scientists believe global warming and as the global temperature rises:

The polar ice sheets and mountain glaciers around the world are melting leading to more water in the sea

The water in the sea gets warmer and expands

Rising Sea Levels - Maldives 2

Impacts on Maldives

Coral reefs will die as they're bleached and the water gets deeper

The ecosystem associated with the reefs will be lost

People will be forced to leave their homes and become environmental refugees

The traditional way of life will be lost

An end may come to the tourism industry

The country might disappear underwater

Managing The Coast - Hard Engineering

Hard engineering - physical structures

Sea wall - Concrete structures which absorb the wave energy and provide a promenade for tourists. Costs £2000 per metre and is a pernament structure that will last for many years

Groynes - Long wooden or rock fences built out into the sea to stop longshore drift and help build up sand on one side. Costs £2000 per metre and stops the transportation of sediment

Rock armour (Rip-rap) - Large boulders piled up at the foot of the cliffs to absorb the energy of the waves and prevent them eroding the cliff. Costs £300 per metre and looks natural

Gabions - Rocks or boulders held in wire mesh cages and used to protect vulnerable areas from destructive waves. Costs £100 per metre and is the cheapest option

Managing The Coast - Hard Engineering 2

For hard engineering

Local people - homes

Local tourist businesses - caravan parks and hotels

Local politicians - support residents and businesses

Againist hard engineering

Local taxpayers - who don't live on the coast

Environmentalists - fear natural habitats and beauty will be affected

People who live down drift - lose their beach

Managing The Coast - Soft Engineering

Beach nourishment - building up beaches by adding more sand infront of the cliffs. It's natural protection as it absorbs wave energy

Sand dune regeneration - allowing sand dunes to building up around wooden structures. Sand dunes absorb wave energy and create new habitats

Salt marsh creation - allowing the sea to flood and spread over a large area creating a salt marsh. New habitats are created and it reduces the risk of flooding along the coast

Managed retreat - Abandoning the exisitng sea defences and building new ones further inland, creating a salt marsh which also floods in storm conditions. Some people will lose land, homes, businesses but new habitats are created and flooding is reduced in other areas

Shoreline Management Plans

There are four main options:

Advance the line - build new, higher and better defences and protect land that is valuable

Hold the line - keep up and improve the exisiting defences

Do nothing - let nature take its course, so erosion takes place but new land is also built up elsewhere

Managed retreat - allow certain areas to flood, so that some areas are protected and some areas are not

Coastal Habitats - Studland Bay Nature Reserve

It has a unique ecosystem - the relationship between plants animals and the environment

Issues

The nature reserve is a vulnerable environment, it took many years to establish and if the habitat is destroyed the ecosystem will break down

The nature reserve is home to rare species of plants and birds

The area attracts many tourists and the beach can get very crowded in the summer

Visitors need somewhere to park, plus other facilities such as toilets and paths

Visitors bring problems such as litter and create fire hazards e.g. cigarette ends

Coastal Habitats - Studland Bay Nature Reserve 2

Solutions

Vulnerable areas and those recently planted with marram grass have been fenced off

Bird-watching hides and guided walks to help visitors to enjoy the wildlife properly

Car-parking spaces are limited and people are not allowed to drive on the beach

Boardwalks have been laid through the dunes to keep tourists on specific paths

Fire beaters have been placed in the dunes incase of fires

Jet skis are not allowed to be launched from the beach and there is a 5mph speed limit to reduce noise

Dogs aren't allowed on the middle beach from July to September

Information boards to educate visitors about the environment and how to help protect it 

Waves

How waves are formed

Out at sea, the wind tugs at the surface of the water, causing the wave shape to move, when the wave moves into shallow water near the coast it is distorted until it 'breaks' then the water moves forward, water rushing up the beach is called the swash and when the water drains back down the beach is called the backwash

Size of a wave

How strong the wind is

How long it blows for

How far it travels

The distance the wind blows over is called a fetch

Wave Types

Destructive waves

The waves have a weak swash and a strong backwash pulling sand and pebbles back down the beach. These are destructives because they remove material from the beach. The characteristics of these waves are steep, high waves that are close together and crash down onto the beach.

Constructive waves

The waves have a very strong swash and a weak backwash as they push sand and pebbles up the beach and leave them behind when the water retreats because the wave isn't strong enough to remove them. They are low waves with gaps between them.

Coastal Erosion

Hydraulic Action - Water forced into the cracks in the rock, compressing the air inside so when the wave retreats, the compressed air blasts out and can force the rock apart.

Abrasion - Loose rocks are thrown againist the cliff by the waves and wears the cliff away and chips rock off

Attrition - Loose sediment knocked off the cliff by hydraulic action and abrasion is swirled around by the waves and collides with other sediment leading to the sediment getting smaller and smaller

Solution - When seawater dissolves material from the rock, it happens along limestone coasts where calcium carbonate is dissolved

Landforms by erosion

Wave-cut notch - Waves hit the bottom of the cliff, eroding a wave-cut notch. The cliff above the notch is undercut and the overhanging rock eventually falls, leaving the steep cliff face.

Wave-cut platform - As the cliff errodes it leaves behind flat rocks and rock pools.

Coastal Erosion 2

Headlands and bays

Where coasts are formed from alternating bands of hard and soft rock. The less-resistant rock will form bays. The more-resistant rock will form headlands.

Caves, arches and stacks

A joint or fault in resistant rock appears, abrasion and hydraulic action widen the joint to form a cave. Waves make the cave larger until it cuts through the headland to form a arch which is eroded so the roof collapses as it becomes to heavy. This leaves a tall stack which is eroded and collapses, leaving a stump

Coastal Transport

Methods of transport

Suspension - Fine sediment is carried as a suspension in the water making it look muddy or murky

Solution - Dissolved material is carried along in solution, so you can't see it

Traction - Larger pebbles and cobbles are rolled along the sea bed

Saltation - Small pebbles are moved when one pebble hits another, causing it to bounce. The bouncing can cause a chain reaction

 Longshore drift                                                                                                             Waves approach the beach at a slight angle, as the waves break, the swash carries material  up the beach at the same angle as the wave approached, as the swash dies away the backwash and any material carried by it falls straight back down the beach under the influence of gravity meaning the material has moved along the beach in a zig-zag route. To prevent longshore drift we build wooden or rock fences called groynes to trap the sediment and stop the transportation along the coast

Coastal Deposition

Spits

Spits are long narrow ridges of sand and shingle stretching out from the coast. They form where longshore drift moves sediment along the coast in the direction of the prevailing wind. When the coastline changes direction, such as at the mouth of a river, the sediment is then deposited as a long ridge, which streches away from the coast to form a spit

Bars

Bars are narrow ridges of sand and shingle that grow across a bay as a result of longshore drift. They can trap lagoons behind them. The lagoon may fill up with sediment eventually. Sometimes storm waves sometimes crash over the top or break through a bar. 

Collapsing Cliffs

Why do cliffs collapse?

Marine processes - The base of the cliff is eroded by hydraulic action and abrasion making the cliff face steeper

Sub-aerial processes - The cliffs are attacked by weathering, loosening the rocks causing them to fall or slide because of gravity

Types of weathering

Mechanical weathering - (Freeze-thaw) When temperatures drop below freezing at night and rise during the day, so the water in the cracks freeze and expands then thaws again which repeats again and again until the rock is weakened and fragments break away

Chemical weathering - (Solution) When water reacts with the calcium carbonate in the rocks e.g. limestone so the calcium carbonate dissolves and is washed away in solution, weakening the rock

Mass Movement

Sliding

When large chunks of rock slide down the slope quickly without any warning, making it very dangerous to walk along the bach under the cliffs

Slumping

Where cliffs are made of clay, the clay becomes saturated during heavy rainfall and oozes down towards the sea as part of a mud or debris flow

Human actions making it worse

Builiding on top of unstable cliffs can put pressure and weight on them adding to the chances of cliff collapse

Cliff Collapse - Holderness Coast

One of the fastest eroding coastlines in Europe

1.8m of land is lost every year e.g. Great Cowden

Reasons for rapid erosion

Easily eroded rock type - the cliffs are made up of clay so its likely to slump

Naturally narrow beaches - beaches slow waves down reducing their power but narrow beaches give less protection

People worsening the situation - groynes have been built at mappleton which stop the material being moved down the coast, so some of the coast having no sediment to protect the cliff face

Powerful waves - Holderness faces the prevailing wind which brings waves from the north east (across the arctic ocean) which is a large distance so the waves gain more power so the coast is battered by highly erosive waves

Cliff Collapse - Holderness Coast 2

Impacts on lives

Homes near cliffs e.g. Skipsea are at risk of collapsing into the sea

Property prices have fallen sharply along the coast as the houses are at risk

Some settlements are not accessible because roads have collapsed into the sea

Businesses are at risk and people will lose their jobs e.g. seaside caravan park looses 10 pitches a year

The gas terminal at Easington is at risk as its near the cliff edge, this terminal powers 25% of Britain's gas supply

80,000m of farmland is lost each year, having a large effect on farmers lives

Environment impacts - the lagoons near Easington are part of the SSSIs (Sites of Special Scientific Interest) If the bar erodes it will connect the lagoon to the sea, destroying it

Rising Sea Levels - Maldives

A small island located in the Indian Ocean with the highest point of the land being 2.4m above sea. Tourism provides 30% of the Maldives GDP

What is happening?

Sea levels are rising and islands in the Pacific Ocean are beginning to disappear. Why? Scientists believe global warming and as the global temperature rises:

The polar ice sheets and mountain glaciers around the world are melting leading to more water in the sea

The water in the sea gets warmer and expands

Rising Sea Levels - Maldives 2

Impacts on Maldives

Coral reefs will die as they're bleached and the water gets deeper

The ecosystem associated with the reefs will be lost

People will be forced to leave their homes and become environmental refugees

The traditional way of life will be lost

An end may come to the tourism industry

The country might disappear underwater

Managing The Coast - Hard Engineering

Hard engineering - physical structures

Sea wall - Concrete structures which absorb the wave energy and provide a promenade for tourists. Costs £2000 per metre and is a pernament structure that will last for many years

Groynes - Long wooden or rock fences built out into the sea to stop longshore drift and help build up sand on one side. Costs £2000 per metre and stops the transportation of sediment

Rock armour (Rip-rap) - Large boulders piled up at the foot of the cliffs to absorb the energy of the waves and prevent them eroding the cliff. Costs £300 per metre and looks natural

Gabions - Rocks or boulders held in wire mesh cages and used to protect vulnerable areas from destructive waves. Costs £100 per metre and is the cheapest option

Managing The Coast - Hard Engineering 2

For hard engineering

Local people - homes

Local tourist businesses - caravan parks and hotels

Local politicians - support residents and businesses

Againist hard engineering

Local taxpayers - who don't live on the coast

Environmentalists - fear natural habitats and beauty will be affected

People who live down drift - lose their beach

Managing The Coast - Soft Engineering

Beach nourishment - building up beaches by adding more sand infront of the cliffs. It's natural protection as it absorbs wave energy

Sand dune regeneration - allowing sand dunes to building up around wooden structures. Sand dunes absorb wave energy and create new habitats

Salt marsh creation - allowing the sea to flood and spread over a large area creating a salt marsh. New habitats are created and it reduces the risk of flooding along the coast

Managed retreat - Abandoning the exisitng sea defences and building new ones further inland, creating a salt marsh which also floods in storm conditions. Some people will lose land, homes, businesses but new habitats are created and flooding is reduced in other areas

Shoreline Management Plans

There are four main options:

Advance the line - build new, higher and better defences and protect land that is valuable

Hold the line - keep up and improve the exisiting defences

Do nothing - let nature take its course, so erosion takes place but new land is also built up elsewhere

Managed retreat - allow certain areas to flood, so that some areas are protected and some areas are not

Coastal Habitats - Studland Bay Nature Reserve

It has a unique ecosystem - the relationship between plants animals and the environment

Issues

The nature reserve is a vulnerable environment, it took many years to establish and if the habitat is destroyed the ecosystem will break down

The nature reserve is home to rare species of plants and birds

The area attracts many tourists and the beach can get very crowded in the summer

Visitors need somewhere to park, plus other facilities such as toilets and paths

Visitors bring problems such as litter and create fire hazards e.g. cigarette ends

Coastal Habitats - Studland Bay Nature Reserve 2

Solutions

Vulnerable areas and those recently planted with marram grass have been fenced off

Bird-watching hides and guided walks to help visitors to enjoy the wildlife properly

Car-parking spaces are limited and people are not allowed to drive on the beach

Boardwalks have been laid through the dunes to keep tourists on specific paths

Fire beaters have been placed in the dunes incase of fires

Jet skis are not allowed to be launched from the beach and there is a 5mph speed limit to reduce noise

Dogs aren't allowed on the middle beach from July to September

Information boards to educate visitors about the environment and how to help protect it 

Waves

How waves are formed

Out at sea, the wind tugs at the surface of the water, causing the wave shape to move, when the wave moves into shallow water near the coast it is distorted until it 'breaks' then the water moves forward, water rushing up the beach is called the swash and when the water drains back down the beach is called the backwash

Size of a wave

How strong the wind is

How long it blows for

How far it travels

The distance the wind blows over is called a fetch

Wave Types

Destructive waves

The waves have a weak swash and a strong backwash pulling sand and pebbles back down the beach. These are destructives because they remove material from the beach. The characteristics of these waves are steep, high waves that are close together and crash down onto the beach.

Constructive waves

The waves have a very strong swash and a weak backwash as they push sand and pebbles up the beach and leave them behind when the water retreats because the wave isn't strong enough to remove them. They are low waves with gaps between them.

Coastal Erosion

Hydraulic Action - Water forced into the cracks in the rock, compressing the air inside so when the wave retreats, the compressed air blasts out and can force the rock apart.

Abrasion - Loose rocks are thrown againist the cliff by the waves and wears the cliff away and chips rock off

Attrition - Loose sediment knocked off the cliff by hydraulic action and abrasion is swirled around by the waves and collides with other sediment leading to the sediment getting smaller and smaller

Solution - When seawater dissolves material from the rock, it happens along limestone coasts where calcium carbonate is dissolved

Landforms by erosion

Wave-cut notch - Waves hit the bottom of the cliff, eroding a wave-cut notch. The cliff above the notch is undercut and the overhanging rock eventually falls, leaving the steep cliff face.

Wave-cut platform - As the cliff errodes it leaves behind flat rocks and rock pools.

Coastal Erosion 2

Headlands and bays

Where coasts are formed from alternating bands of hard and soft rock. The less-resistant rock will form bays. The more-resistant rock will form headlands.

Caves, arches and stacks

A joint or fault in resistant rock appears, abrasion and hydraulic action widen the joint to form a cave. Waves make the cave larger until it cuts through the headland to form a arch which is eroded so the roof collapses as it becomes to heavy. This leaves a tall stack which is eroded and collapses, leaving a stump

Coastal Transport

Methods of transport

Suspension - Fine sediment is carried as a suspension in the water making it look muddy or murky

Solution - Dissolved material is carried along in solution, so you can't see it

Traction - Larger pebbles and cobbles are rolled along the sea bed

Saltation - Small pebbles are moved when one pebble hits another, causing it to bounce. The bouncing can cause a chain reaction

 Longshore drift                                                                                                             Waves approach the beach at a slight angle, as the waves break, the swash carries material  up the beach at the same angle as the wave approached, as the swash dies away the backwash and any material carried by it falls straight back down the beach under the influence of gravity meaning the material has moved along the beach in a zig-zag route. To prevent longshore drift we build wooden or rock fences called groynes to trap the sediment and stop the transportation along the coast

Coastal Deposition

Spits

Spits are long narrow ridges of sand and shingle stretching out from the coast. They form where longshore drift moves sediment along the coast in the direction of the prevailing wind. When the coastline changes direction, such as at the mouth of a river, the sediment is then deposited as a long ridge, which streches away from the coast to form a spit

Bars

Bars are narrow ridges of sand and shingle that grow across a bay as a result of longshore drift. They can trap lagoons behind them. The lagoon may fill up with sediment eventually. Sometimes storm waves sometimes crash over the top or break through a bar. 

Collapsing Cliffs

Why do cliffs collapse?

Marine processes - The base of the cliff is eroded by hydraulic action and abrasion making the cliff face steeper

Sub-aerial processes - The cliffs are attacked by weathering, loosening the rocks causing them to fall or slide because of gravity

Types of weathering

Mechanical weathering - (Freeze-thaw) When temperatures drop below freezing at night and rise during the day, so the water in the cracks freeze and expands then thaws again which repeats again and again until the rock is weakened and fragments break away

Chemical weathering - (Solution) When water reacts with the calcium carbonate in the rocks e.g. limestone so the calcium carbonate dissolves and is washed away in solution, weakening the rock

Mass Movement

Sliding

When large chunks of rock slide down the slope quickly without any warning, making it very dangerous to walk along the bach under the cliffs

Slumping

Where cliffs are made of clay, the clay becomes saturated during heavy rainfall and oozes down towards the sea as part of a mud or debris flow

Human actions making it worse

Builiding on top of unstable cliffs can put pressure and weight on them adding to the chances of cliff collapse

Cliff Collapse - Holderness Coast

One of the fastest eroding coastlines in Europe

1.8m of land is lost every year e.g. Great Cowden

Reasons for rapid erosion

Easily eroded rock type - the cliffs are made up of clay so its likely to slump

Naturally narrow beaches - beaches slow waves down reducing their power but narrow beaches give less protection

People worsening the situation - groynes have been built at mappleton which stop the material being moved down the coast, so some of the coast having no sediment to protect the cliff face

Powerful waves - Holderness faces the prevailing wind which brings waves from the north east (across the arctic ocean) which is a large distance so the waves gain more power so the coast is battered by highly erosive waves

Cliff Collapse - Holderness Coast 2

Impacts on lives

Homes near cliffs e.g. Skipsea are at risk of collapsing into the sea

Property prices have fallen sharply along the coast as the houses are at risk

Some settlements are not accessible because roads have collapsed into the sea

Businesses are at risk and people will lose their jobs e.g. seaside caravan park looses 10 pitches a year

The gas terminal at Easington is at risk as its near the cliff edge, this terminal powers 25% of Britain's gas supply

80,000m of farmland is lost each year, having a large effect on farmers lives

Environment impacts - the lagoons near Easington are part of the SSSIs (Sites of Special Scientific Interest) If the bar erodes it will connect the lagoon to the sea, destroying it

Rising Sea Levels - Maldives

A small island located in the Indian Ocean with the highest point of the land being 2.4m above sea. Tourism provides 30% of the Maldives GDP

What is happening?

Sea levels are rising and islands in the Pacific Ocean are beginning to disappear. Why? Scientists believe global warming and as the global temperature rises:

The polar ice sheets and mountain glaciers around the world are melting leading to more water in the sea

The water in the sea gets warmer and expands

Rising Sea Levels - Maldives 2

Impacts on Maldives

Coral reefs will die as they're bleached and the water gets deeper

The ecosystem associated with the reefs will be lost

People will be forced to leave their homes and become environmental refugees

The traditional way of life will be lost

An end may come to the tourism industry

The country might disappear underwater

Managing The Coast - Hard Engineering

Hard engineering - physical structures

Sea wall - Concrete structures which absorb the wave energy and provide a promenade for tourists. Costs £2000 per metre and is a pernament structure that will last for many years

Groynes - Long wooden or rock fences built out into the sea to stop longshore drift and help build up sand on one side. Costs £2000 per metre and stops the transportation of sediment

Rock armour (Rip-rap) - Large boulders piled up at the foot of the cliffs to absorb the energy of the waves and prevent them eroding the cliff. Costs £300 per metre and looks natural

Gabions - Rocks or boulders held in wire mesh cages and used to protect vulnerable areas from destructive waves. Costs £100 per metre and is the cheapest option

Managing The Coast - Hard Engineering 2

For hard engineering

Local people - homes

Local tourist businesses - caravan parks and hotels

Local politicians - support residents and businesses

Againist hard engineering

Local taxpayers - who don't live on the coast

Environmentalists - fear natural habitats and beauty will be affected

People who live down drift - lose their beach

Managing The Coast - Soft Engineering

Beach nourishment - building up beaches by adding more sand infront of the cliffs. It's natural protection as it absorbs wave energy

Sand dune regeneration - allowing sand dunes to building up around wooden structures. Sand dunes absorb wave energy and create new habitats

Salt marsh creation - allowing the sea to flood and spread over a large area creating a salt marsh. New habitats are created and it reduces the risk of flooding along the coast

Managed retreat - Abandoning the exisitng sea defences and building new ones further inland, creating a salt marsh which also floods in storm conditions. Some people will lose land, homes, businesses but new habitats are created and flooding is reduced in other areas

Shoreline Management Plans

There are four main options:

Advance the line - build new, higher and better defences and protect land that is valuable

Hold the line - keep up and improve the exisiting defences

Do nothing - let nature take its course, so erosion takes place but new land is also built up elsewhere

Managed retreat - allow certain areas to flood, so that some areas are protected and some areas are not

Coastal Habitats - Studland Bay Nature Reserve

It has a unique ecosystem - the relationship between plants animals and the environment

Issues

The nature reserve is a vulnerable environment, it took many years to establish and if the habitat is destroyed the ecosystem will break down

The nature reserve is home to rare species of plants and birds

The area attracts many tourists and the beach can get very crowded in the summer

Visitors need somewhere to park, plus other facilities such as toilets and paths

Visitors bring problems such as litter and create fire hazards e.g. cigarette ends

Coastal Habitats - Studland Bay Nature Reserve 2

Solutions

Vulnerable areas and those recently planted with marram grass have been fenced off

Bird-watching hides and guided walks to help visitors to enjoy the wildlife properly

Car-parking spaces are limited and people are not allowed to drive on the beach

Boardwalks have been laid through the dunes to keep tourists on specific paths

Fire beaters have been placed in the dunes incase of fires

Jet skis are not allowed to be launched from the beach and there is a 5mph speed limit to reduce noise

Dogs aren't allowed on the middle beach from July to September

Information boards to educate visitors about the environment and how to help protect it 

Waves

How waves are formed

Out at sea, the wind tugs at the surface of the water, causing the wave shape to move, when the wave moves into shallow water near the coast it is distorted until it 'breaks' then the water moves forward, water rushing up the beach is called the swash and when the water drains back down the beach is called the backwash

Size of a wave

How strong the wind is

How long it blows for

How far it travels

The distance the wind blows over is called a fetch

Wave Types

Destructive waves

The waves have a weak swash and a strong backwash pulling sand and pebbles back down the beach. These are destructives because they remove material from the beach. The characteristics of these waves are steep, high waves that are close together and crash down onto the beach.

Constructive waves

The waves have a very strong swash and a weak backwash as they push sand and pebbles up the beach and leave them behind when the water retreats because the wave isn't strong enough to remove them. They are low waves with gaps between them.

Coastal Erosion

Hydraulic Action - Water forced into the cracks in the rock, compressing the air inside so when the wave retreats, the compressed air blasts out and can force the rock apart.

Abrasion - Loose rocks are thrown againist the cliff by the waves and wears the cliff away and chips rock off

Attrition - Loose sediment knocked off the cliff by hydraulic action and abrasion is swirled around by the waves and collides with other sediment leading to the sediment getting smaller and smaller

Solution - When seawater dissolves material from the rock, it happens along limestone coasts where calcium carbonate is dissolved

Landforms by erosion

Wave-cut notch - Waves hit the bottom of the cliff, eroding a wave-cut notch. The cliff above the notch is undercut and the overhanging rock eventually falls, leaving the steep cliff face.

Wave-cut platform - As the cliff errodes it leaves behind flat rocks and rock pools.

Coastal Erosion 2

Headlands and bays

Where coasts are formed from alternating bands of hard and soft rock. The less-resistant rock will form bays. The more-resistant rock will form headlands.

Caves, arches and stacks

A joint or fault in resistant rock appears, abrasion and hydraulic action widen the joint to form a cave. Waves make the cave larger until it cuts through the headland to form a arch which is eroded so the roof collapses as it becomes to heavy. This leaves a tall stack which is eroded and collapses, leaving a stump

Coastal Transport

Methods of transport

Suspension - Fine sediment is carried as a suspension in the water making it look muddy or murky

Solution - Dissolved material is carried along in solution, so you can't see it

Traction - Larger pebbles and cobbles are rolled along the sea bed

Saltation - Small pebbles are moved when one pebble hits another, causing it to bounce. The bouncing can cause a chain reaction

 Longshore drift                                                                                                             Waves approach the beach at a slight angle, as the waves break, the swash carries material  up the beach at the same angle as the wave approached, as the swash dies away the backwash and any material carried by it falls straight back down the beach under the influence of gravity meaning the material has moved along the beach in a zig-zag route. To prevent longshore drift we build wooden or rock fences called groynes to trap the sediment and stop the transportation along the coast

Coastal Deposition

Spits

Spits are long narrow ridges of sand and shingle stretching out from the coast. They form where longshore drift moves sediment along the coast in the direction of the prevailing wind. When the coastline changes direction, such as at the mouth of a river, the sediment is then deposited as a long ridge, which streches away from the coast to form a spit

Bars

Bars are narrow ridges of sand and shingle that grow across a bay as a result of longshore drift. They can trap lagoons behind them. The lagoon may fill up with sediment eventually. Sometimes storm waves sometimes crash over the top or break through a bar. 

Collapsing Cliffs

Why do cliffs collapse?

Marine processes - The base of the cliff is eroded by hydraulic action and abrasion making the cliff face steeper

Sub-aerial processes - The cliffs are attacked by weathering, loosening the rocks causing them to fall or slide because of gravity

Types of weathering

Mechanical weathering - (Freeze-thaw) When temperatures drop below freezing at night and rise during the day, so the water in the cracks freeze and expands then thaws again which repeats again and again until the rock is weakened and fragments break away

Chemical weathering - (Solution) When water reacts with the calcium carbonate in the rocks e.g. limestone so the calcium carbonate dissolves and is washed away in solution, weakening the rock

Mass Movement

Sliding

When large chunks of rock slide down the slope quickly without any warning, making it very dangerous to walk along the bach under the cliffs

Slumping

Where cliffs are made of clay, the clay becomes saturated during heavy rainfall and oozes down towards the sea as part of a mud or debris flow

Human actions making it worse

Builiding on top of unstable cliffs can put pressure and weight on them adding to the chances of cliff collapse

Cliff Collapse - Holderness Coast

One of the fastest eroding coastlines in Europe

1.8m of land is lost every year e.g. Great Cowden

Reasons for rapid erosion

Easily eroded rock type - the cliffs are made up of clay so its likely to slump

Naturally narrow beaches - beaches slow waves down reducing their power but narrow beaches give less protection

People worsening the situation - groynes have been built at mappleton which stop the material being moved down the coast, so some of the coast having no sediment to protect the cliff face

Powerful waves - Holderness faces the prevailing wind which brings waves from the north east (across the arctic ocean) which is a large distance so the waves gain more power so the coast is battered by highly erosive waves

Cliff Collapse - Holderness Coast 2

Impacts on lives

Homes near cliffs e.g. Skipsea are at risk of collapsing into the sea

Property prices have fallen sharply along the coast as the houses are at risk

Some settlements are not accessible because roads have collapsed into the sea

Businesses are at risk and people will lose their jobs e.g. seaside caravan park looses 10 pitches a year

The gas terminal at Easington is at risk as its near the cliff edge, this terminal powers 25% of Britain's gas supply

80,000m of farmland is lost each year, having a large effect on farmers lives

Environment impacts - the lagoons near Easington are part of the SSSIs (Sites of Special Scientific Interest) If the bar erodes it will connect the lagoon to the sea, destroying it

Rising Sea Levels - Maldives

A small island located in the Indian Ocean with the highest point of the land being 2.4m above sea. Tourism provides 30% of the Maldives GDP

What is happening?

Sea levels are rising and islands in the Pacific Ocean are beginning to disappear. Why? Scientists believe global warming and as the global temperature rises:

The polar ice sheets and mountain glaciers around the world are melting leading to more water in the sea

The water in the sea gets warmer and expands

Rising Sea Levels - Maldives 2

Impacts on Maldives

Coral reefs will die as they're bleached and the water gets deeper

The ecosystem associated with the reefs will be lost

People will be forced to leave their homes and become environmental refugees

The traditional way of life will be lost

An end may come to the tourism industry

The country might disappear underwater

Managing The Coast - Hard Engineering

Hard engineering - physical structures

Sea wall - Concrete structures which absorb the wave energy and provide a promenade for tourists. Costs £2000 per metre and is a pernament structure that will last for many years

Groynes - Long wooden or rock fences built out into the sea to stop longshore drift and help build up sand on one side. Costs £2000 per metre and stops the transportation of sediment

Rock armour (Rip-rap) - Large boulders piled up at the foot of the cliffs to absorb the energy of the waves and prevent them eroding the cliff. Costs £300 per metre and looks natural

Gabions - Rocks or boulders held in wire mesh cages and used to protect vulnerable areas from destructive waves. Costs £100 per metre and is the cheapest option

Managing The Coast - Hard Engineering 2

For hard engineering

Local people - homes

Local tourist businesses - caravan parks and hotels

Local politicians - support residents and businesses

Againist hard engineering

Local taxpayers - who don't live on the coast

Environmentalists - fear natural habitats and beauty will be affected

People who live down drift - lose their beach

Managing The Coast - Soft Engineering

Beach nourishment - building up beaches by adding more sand infront of the cliffs. It's natural protection as it absorbs wave energy

Sand dune regeneration - allowing sand dunes to building up around wooden structures. Sand dunes absorb wave energy and create new habitats

Salt marsh creation - allowing the sea to flood and spread over a large area creating a salt marsh. New habitats are created and it reduces the risk of flooding along the coast

Managed retreat - Abandoning the exisitng sea defences and building new ones further inland, creating a salt marsh which also floods in storm conditions. Some people will lose land, homes, businesses but new habitats are created and flooding is reduced in other areas

Shoreline Management Plans

There are four main options:

Advance the line - build new, higher and better defences and protect land that is valuable

Hold the line - keep up and improve the exisiting defences

Do nothing - let nature take its course, so erosion takes place but new land is also built up elsewhere

Managed retreat - allow certain areas to flood, so that some areas are protected and some areas are not

Coastal Habitats - Studland Bay Nature Reserve

It has a unique ecosystem - the relationship between plants animals and the environment

Issues

The nature reserve is a vulnerable environment, it took many years to establish and if the habitat is destroyed the ecosystem will break down

The nature reserve is home to rare species of plants and birds

The area attracts many tourists and the beach can get very crowded in the summer

Visitors need somewhere to park, plus other facilities such as toilets and paths

Visitors bring problems such as litter and create fire hazards e.g. cigarette ends

Coastal Habitats - Studland Bay Nature Reserve 2

Solutions

Vulnerable areas and those recently planted with marram grass have been fenced off

Bird-watching hides and guided walks to help visitors to enjoy the wildlife properly

Car-parking spaces are limited and people are not allowed to drive on the beach

Boardwalks have been laid through the dunes to keep tourists on specific paths

Fire beaters have been placed in the dunes incase of fires

Jet skis are not allowed to be launched from the beach and there is a 5mph speed limit to reduce noise

Dogs aren't allowed on the middle beach from July to September

Information boards to educate visitors about the environment and how to help protect it 

Likely Effects of a Supervolcano Eruption

- Yellowstone Supervolcano

- 87000 deaths predicted within area of eruption

- 10,000 km^2 land destroyed

- 15cm of ash covering buildings within 10,000 km

- Ash cloud rising 40-50 km into the atmosphere

- Flights suspended

- Constant snow cover in America and Asia for 3 years

  • Monsoon rains would fail
  • 40% of population suffering starvation

Earthquake in MEDC : Kobe Earthquake

- 5:46am on 17th Jan 1995 at Nojima fault line

- Earthquake measuring 7.2 on Richter Scale

  • 6,500 dead
  • 40,000 seriously injured
  • 300,000 homeless
  • Huge damage to buildings (30% of Osaka to Kobe tracks left)
  • Hanshin Expressway destroyed
  • 1 million homes without water for 10 days
  • $220 billion worth of damage

- Responses

  • Emergency services searched for survivors in rubble
  • Hospitals working non-stop
  • Motorola gave telephone connections for free
  • New laws for building of earthquake proof buildings

Earthquake in LEDC : The Sichuan Earthquake

- 12 May  2008, 2:28pm. Indian Plate collided with the Eurasian Plate along Longmenshan fault line.

-  7.9 on the Richter Scale, tremors lasting 120 seconds

  • 70,000 dead + 20,000 missing
  • 400,000 injured
  • 10 million homeless
  • 80% buildings collapsed due to cheap building materials
  • Lack of communications, limited access by roads due to landslides, and flooding
  • $75 million worth of damage

- Responses

  • 20 helicopters assingned to rescuse survivors
  • Provisions of shelter, water and food
  • £100 million of donations by the Red Cross
  • Debts of survivors written off

Volcanic Eruption : Mt St Helens

- 8:32am, 18 May 1980

The were signs of an eruption in March 1980, so evacuation had been carried out

  • Magnitude: 5.1
  • Caused the biggest landslide ever recorded
  • All living organisms 27km to the north of volcano wiped out.
  • 57 dead

- Responses

  • Helicopters mobilised for search and rescue
  • Ash was cleared from roads within 3 days
  • Masks provided to locals to aid breathing
  • Housing reconstructed
  • Forest replanted + Road rebuilt
  • Over time, animals like elks returned
  • Much more fertile soils left behind

Indian Ocean Tsunami

- 26 December 2004, when Indo-Australian Plate subducted beneath the Eurasian Plate

  • Earthquake measured 9.1 on Richter Scale
  • Highest wave : 25m
  • 220,000 dead ; 650,000 seriously injured ; 2 million homeless

- Responses

  • Vast area affected meant that rescue services could not help everyone
    • Diseases spread and wounds worsened
  • Fresh water + food and shelter provided
  • £372 million donations from UK
  • Indian Ocean Tsunami Warning System set up in June 2006

- Specific Areas Afffected

  • Banda Aceh in Sumatra - people swept away
  • Two-thirds of the Maldives' low lying capital, Male, inundated

The Andes

- Uses

  • Farming
    • Mountain slopes used for subsidence farming, such as potatoes
    • Terraces used to retain water and make farming easier. Most farming in the lower valleys
    • Using llamas to carry materials for irrigation and for meat, milk and wool
  • Mining
    • Range of important minerals - Tin from Peru and Bolivia ; Gold from Peru (Yanacocha goldmine)
    • Provides jobs
  • Hydroelectric Power
    • Steep slopes used to generate hydroelectric power, eg Yuncan project dams the Paucartambo and Huachon rivers
  • Tourism
    • Trails for hiking : Inca Trail ; Heritage Sites : Machu Picchu

Tourism in the Alps: Chamonix

- Located in the north-westerly part of the Alps in France. 100,000 visitors every day 

  • Winter Attractions
    • Skiing + Snowboarding + Ice Climbing + Paragliding
    • Hotels, Restaurants, Heated swimming pools and Museums within Chamonix
  • Summer Attractions
    • Montenvers railway takes visitors to the Mer de Glace (glacier) with ice caves
    • 350km of hiking trails + Boating + Rock Climbing
    • Live music, cafes and flowers within Chamonix
  • Impact of tourists
    • Employment + Improvement of local facilities and town appearence
    • Noisy + Congested at times due to small roads.
    • Erosion of mountain footpaths
    • Shops become expensive for locals
    • Conflicts can arise beteen tourists and locals.
  • Management
    • Promotion of responsible tourism + Offers eco-friendly transport
    • Espace Mont-Blanc Initiative and Tomorrow's Valley Organisation

Temperate Deciduous Forest: Epping Forest

- North-east of London; covers 2,500 ha (19km long x 4km wide)

  • Wide variety of environments such as woodland, grasslands and marshes
  • Early Uses and Managment
    • Hunting; Collecting wood; Grazing
    • Pollarding; Made a conservation site to prevent people buying it
  •  
  • Recent Management
    • 1,500 ha designated as an SSSI
    • Provision of facilities for tourists like car parks and toilets to limit damage to forest
    • Controlling some forms of recreation to limit damage
    • Preserving ancient trees by pllarding (1,000 trees repollarded since 1981)
    • Preserving animals living there
    • Encouraging grazing to maintain soil fertility

Deforestation of a tropical rainforest: Malasiya

- Located south-east Asia. 63% of Malasiya is tropical rainforest

  • Dangers
    • 150,000ha of forest lost every year
    • Clear felling of trees leads to total destruction of rainforest
    • $2bn Bakun Dam project resulted in the flooding of 1000s of hectares of rainforest
      • 250 km^2 of virgin rainforest cut down
      • 9,000 indigenous people forced to move from the area but not supplied with rehousing
    • Areas of rainforest cleared for mining, leading to pollution of land and rivers
    • Drilling has started in Borneo, as well as deforestation for palm oil plantations
    • Land cleared for countryside population
    • Fires are common due to "slash and burn" methods

Desert in LEDC: Thar Desert, Rajasthan, India

  • Economic Uses
    • Susidence farming of basic crop, as well as hunters
    • Irrigation and Commercial Farming
      • Indira Gandhi Canal - 650km long - irrigates 3,500 km^2 of land in Jodhpur and Jaisalmer, allowing commercial farming of wheat and provides drinking water to people in the desert
    • Mining Industry
      • Rajasthan has a good supply of kaolin and gypsum
      • At Jaisalmer, the Sanu limestone, the main source of limestone for Indian steel works
      • Rock marble quarried near Jodhpur
    • Tourism
      • Desert safaris on camels at Jaisalmer.
  • Problems and Management
    • Growing population leads to the destruction of land and ecosystems
    • Salinisation has occured due to excessive irrigation + Soil erosion due to over grazing
    • Desert Development Program started to preserve ecological balance of the desert and stabilising sand dunes
    • The Thar Desert National Park has been created to protect 3,000 km^2 of land

Desert in MEDC : Sonoran Desert, Arizona, USA

- 300+ mm of rainfall every year

  • Air conditioning is used to deal with heat, preventing the need to convert the land
  • Good water supply can be used for irrigation and drinking supplies
  • Clean air and open spaces allows tourist sites to be built to generate money

- Manara, a town in the Sonoran Desert

  • Population of 30,000
  • In 1920, a new irrigation system allowed the commercial farming of cotton, wheat and barley
  • Since 1990s, farming has decline and replaced by housing and a heritage park has been opened
  • The town has become a wealthy business community and hosts golfs Matchplay Championship
  • Management
    • 1998, Sonoran Desert Conservation Plan initiated to conserve resources
      • Led to the creation of buffer zones of ecological significance
      • Provides home design recommendations to conserve energy and water

Khumbu Glacier, Nepal

- Starts on the Western corrie on the slopes of Mt. Everest

- Largest glacier in Nepal - 4km long

  • Since 1980, the glaciers have been retreating. The process increased in 1995
  • Between 1976 and 2007, scientists found that the Khumbu glacier retreated by 18m a year

- Melting glaciers causes rivers flowing through Nepal and India can flood

- In 2010, cameras were set up in Mount Everest to monitor glaciers for 2 years.

  • This will allow scientists to plan for the future of Nepal

Management of Malaysia Rainforest

  • Management
    • National Forestry Act - banning of sale of raw timer ; timber processing to reduce demand for raw timber; increase awareness of forests
    • Selective Management System - A system in which scientists decide which trees should be felled and in which direction. After felling, the trees are replanted and allowed to grow
    • Permanent Forest Estates - ban commercial activity in virgin rainforest areas
    • Forest Stewardship Council - promotes the purchase of wood from sustailable sources, rather than rare hardwood
    • Ecotourism - allows locals to make a living without damaging the environment
    • Debt Relief - Paying countries to maintain rainforests or cutting their debts in exchange for rainforest maintainence
    • Carbon Sinks - Large forests maintained to reduce CO2 in the air. Eg Gola Forest in Sierra Leone (supported by European Commission and the French government)

Fragile Environment : Abondance, France

  • The resort has had over 15 years of unreliable snowfall. 
  • People are considering: Developing other forms of winter sports or add summer activities to make the resort availiable all year round.
  • New developments:
    • High Alps are being built on to make more resorts
    • Roads, housing and ski lifts are damaging habitats and the ecosystem
    • Trees are cut down (they bind the soil), which can make avalanches more likely
    • Footpath erosion can leave scars on the landscape.
    • Increasing visual and noise pollution reduces the attractiveness of the resort
  • In Austria, the Gepatsch Glacier is being opened for skiing
  • Cable cars are being used to transport skiers upland

Product Portfolios: Extending Life of Products

Firms can extend the life of products by making changes to the design or offering discounts. If this works the product will profit for longer. However more money must be spent on the product. Firms must get balance between old/new products.

Product Portfolios: Broadening Product Profits

Businesses can broaden portfolios to compete with other companies. Adding products to an existing range by developing new products based on existing ones OR increasing range by developing products that are slightly different from current ones.

Market-Led Pricing: Penetration Pricing

When a firm charges a very low price when the product is new to get lots of people interested in it. 

Market-Led Pricing: Loss Leader Pricing

When a product is set below cost. Once the product is established the firm will increase the price. This happens with new consumer products where existing products have brand loyalty.

Market-Led Pricing: Price Skimming

The opposite of penetration pricing. Firms charge a high price to begin with to apply to a higher market and to make the product a desirable one. Then, when the product is established the firm will lower the price to help it become a mass market product. This happens a lot with consumer goods based on new technology e.g. TVs.

Market-Led Pricing: Competitive Pricing

Where the firm has to charge similar prices to other firms. This happens most when there's lots of competitor choice and not much product differentiation (e.g. petrol)

Cost-Plus Pricing: Profit Margin

Work out how much product costs and increase by required profit margin. e.g. product costs £2 to make and you want a 20% profit margin, £2 is 80% the required selling price. 80%=200p->1%=200p÷80=2.5p->100%=2.5px100=250p You'd sell it for £2.50

Cost-Plus Pricing: Mark-Up

Work out how much the product costs and then add a %age mark up. e.g. if a product costs £2 to make and you want a 25% mark up, you'd sell it for £2+25%=£2.50

Seven Methods of Sales Promotion

Discounts - Products Trials - Free Gifts - Buy One Get One Free - Competitions - Point-of-sale advertising - Use of credit

Promotion: Direct Marketing

Goes straight to the customer without going through other media. Usually some sort of voucher sent in the post. Requires customer to make a direct response. The business can measure its success with this. However this creates junk mail/spam email.

Promotion: Business Sponsors

Businesses can help pay for events such as sports tournaments, TV shows and exhibitions. In return, their name is displayed at the event for publicity. Sponsorship can create a high profile for your business/brand name BUT if the thing you're sponsoring starts to get bad publicity, your business will suffer too. Sports/TV/The Arts are all a few places for sponsorship. 

Place: Distribution Channels

There are 4 main distribution channels. 1, 2 and 3 are indirect and 4 is direct. 

1) MANUFACTURER - WHOLESALER - CONSUMER

Here, consumer buys the product from a cash and carry. Its good for the manufacturer because they get bulk orders and the wholesaler takes the cost of storing the products and the risk of not selling them. Consumer often pays lower prices than if they bought from a retailer - levels of customer service may be lower.  

2) MANUFACTURER - WHOLESALER - RETAILER - CONSUMER

The traditional route. Commonly used in the food and drink industry. Advantages to the manufacturer are the same as channel 1. Retailers also benefit from dealing with the Wholesaler - they reduce risk by allowing retailers to buy in smaller quantities and giving a wide choice of goods. However, goods can take a long time to get from manufacturer to consumer. 

3) MANUFACTURER - RETAILER - CONSUMER

This route is becomming more common. Often used in clothing industry. Faster than dealing with retailers through wholesalers and the manufacturer gets consumer feedback about the products. Harder for small retailers to to avoid having to hold lots of stock. 

4) MANUFACTURER - CONSUMER

Now very popular. Used in factory shops, mail order, tele sales and internet selling. The fastest and often, cheapest channel for consumer. Can be more difficult for consumers to shop around (manufacturers usually only sell their own products, but a retailer would probably stock goods from a range of manufacturers) and customer service may not be as good. 

Sources Of Finance

Larger firms find it easier to raise finiance than smaller firms. Being bigger and more established means they're less likely to go bust. They are less of a credit risk to banks. established firms can get finanace from various sources. 

Sources Of Finance: RETAINED PROFITS

Profits tht owners have decided to plough back into the business fter they've paid themselves a dividend. However larger companies (e.g. PLCs) are under pressure from shareholders to give large dividends, reducing the amount of profit they can retain. 

Sources Of Finance: RE-INVESTED SAVINGS

Large, successful firms may have used retained profit from previous years to build up bank savings or buy stocks or shares. They can use these to get cash quickly if they need it but when it's gone, it's gone. 

Sources Of Finance: FIXED ASSETS

Firms can raise cash by selling fixed assets (e.g. machinery/buildings) that are no longer in use. There is a limit to how many assets you can sell - sell too many and you can't go on trading. 

Sources Of Finance: SHARES

A limited company can issue more shares. The money raised doesn't have to be repaid to shareholders BUT more shares means less control for existing owners. 

Sources Of Finance: DEBENTURES

Limited companies can issue debentures to the public. These are long-term loans which the firm commits itself to repay with interest. People who are issued with debentures don't own any part

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Coastal Deposition

Spits

Spits are long narrow ridges of sand and shingle stretching out from the coast. They form where longshore drift moves sediment along the coast in the direction of the prevailing wind. When the coastline changes direction, such as at the mouth of a river, the sediment is then deposited as a long ridge, which stretches away from the coast to form a spit

Bars

Bars are narrow ridges of sand and shingle that grow across a bay as a result of longshore drift. They can trap lagoons behind them. The lagoon may fill up with sediment eventually. Sometimes storm waves sometimes crash over the top or breakthrough a bar

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Collapsing Cliffs

Why do cliffs collapse?

Marine processes - The base of the cliff is eroded by hydraulic action and abrasion making the cliff face steeper

Sub-aerial processes - The cliffs are attacked by weathering, loosening the rocks causing them to fall or slide because of gravity

Types of weathering

Mechanical weathering - (Freeze-thaw) When temperatures drop below freezing at night and rise during the day, so the water in the cracks freezes and expands then thaws again which repeats again and again until the rock is weakened and fragments breakaway

Chemical weathering - (Solution) When water reacts with the calcium carbonate in the rocks e.g. limestone so the calcium carbonate dissolves and is washed away in solution, weakening the rock

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Mass Movement

Sliding

When large chunks of rock slide down the slope quickly without any warning, making it very dangerous to walk along the beach under the cliffs

Slumping

Where cliffs are made of clay, the clay becomes saturated during heavy rainfall and oozes down towards the sea as part of a mud or debris flow

Human actions making it worse

Building on top of unstable cliffs can put pressure and weight on them adding to the chances of cliff collapse

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Cliff Collapse - Holderness Coast

One of the fastest eroding coastlines in Europe

1.8m of land is lost every year e.g. Great Cowden

Reasons for rapid erosion

Easily eroded rock type - the cliffs are made up of clay so its likely to slump

Naturally narrow beaches - beaches slow waves down reducing their power but narrow beaches give less protection

People worsening the situation - groynes have been built at Mapleton which stop the material being moved down the coast, so some of the coast having no sediment to protect the cliff face

Powerful waves - Holderness faces the prevailing wind which brings waves from the northeast (across the arctic ocean) which is a large distance so the waves gain more power so the coast is battered by highly erosive waves

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Cliff Collapse - Holderness Coast

Impacts on lives

Homes near cliffs e.g. Skipsea are at risk of collapsing into the sea

Property prices have fallen sharply along the coast as the houses are at risk

Some settlements are not accessible because roads have collapsed into the sea

Businesses are at risk and people will lose their jobs e.g. seaside caravan park loses 10 pitches a year

The gas terminal at Easington is at risk as it is near the cliff edge, this terminal powers 25% of Britain's gas supply

80,000m of farmland is lost each year, having a large effect on farmers lives

Environment impacts - the lagoons near Easington are part of the SSSIs (Sites of Special Scientific Interest) If the bar erodes it will connect the lagoon to the sea, destroying it

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Rising Sea Levels - Maldives

A small island located in the Indian Ocean with the highest point of the land being 2.4m above the sea. Tourism provides 30% of the Maldives GDP

What is happening?

Sea levels are rising and islands in the Pacific Ocean are beginning to disappear. Why? Scientists believe global warming and as the global temperature rises:

The polar ice sheets and mountain glaciers around the world are melting leading to more water in the sea

The water in the sea gets warmer and expands

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Rising Sea Levels - Maldives

Impacts on the Maldives

Coral reefs will die as they're bleached and the water gets deeper

The ecosystem associated with the reefs will be lost

People will be forced to leave their homes and become environmental refugees

The traditional way of life will be lost

An end may come to the tourism industry

The country might disappear underwater

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Managing The Coast - Hard Engineering

Hard engineering - physical structures

Sea wall - Concrete structures which absorb the wave energy and provide a promenade for tourists. Costs £2000 per metre and is a permanent structure that will last for many years

Groynes - Long wooden or rock fences built out into the sea to stop longshore drift and help build up sand on one side. Costs £2000 per metre and stops the transportation of sediment

Rock armour (Rip-rap) - Large boulders piled up at the foot of the cliffs to absorb the energy of the waves and prevent them from eroding the cliff. Costs £300 per metre and looks natural

Gabions - Rocks or boulders held in wire mesh cages and used to protect vulnerable areas from destructive waves. Costs £100 per metre and are the cheapest option

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Managing The Coast - Hard Engineering

For hard engineering

Local people - homes

Local tourist businesses - caravan parks and hotels

Local politicians - support residents and businesses

Against hard engineering

Local taxpayers - who don't live on the coast

Environmentalists - fear natural habitats and beauty will be affected

People who live down drift - lose their beach

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Managing The Coast - Soft Engineering

Beach nourishment - building up beaches by adding more sand in front of the cliffs. It's natural protection as it absorbs wave energy

Sand dune regeneration - allowing sand dunes to building up around wooden structures. Sand dunes absorb wave energy and create new habitats

Saltmarsh creation - allowing the sea to flood and spread over a large area creating a salt marsh. New habitats are created and it reduces the risk of flooding along the coast

Managed retreat - Abandoning the existing sea defences and building new ones further inland, creating a salt marsh which also floods in storm conditions. Some people will lose land, homes, businesses but new habitats are created and flooding is reduced in other areas

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Shoreline Management Plans

There are four main options:

Advance the line - build new, higher and better defences and protect land that is valuable

Hold the line - keep up and improve the existing defences

Do nothing - let nature take its course, so erosion takes place but new land is also built up elsewhere

Managed retreat - allow certain areas to flood so that some areas are protected and some areas are not

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Coastal Habitats - Studland Bay Nature Reserve

It has a unique ecosystem - the relationship between plants animals and the environment

Issues

The nature reserve is a vulnerable environment, it took many years to establish and if the habitat is destroyed the ecosystem will break down

The nature reserve is home to rare species of plants and birds

The area attracts many tourists and the beach can get very crowded in the summer

Visitors need somewhere to park, plus other facilities such as toilets and paths

Visitors bring problems such as litter and create fire hazards e.g. cigarette ends

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Coastal Habitats - Studland Bay Nature Reserve

Solutions

Vulnerable areas and those recently planted with marram grass have been fenced off

Bird-watching hides and guided walks to help visitors to enjoy the wildlife properly

Car-parking spaces are limited and people are not allowed to drive on the beach

Boardwalks have been laid through the dunes to keep tourists on specific paths

Fire beaters have been placed in the dunes in case of fires

Jet skis are not allowed to be launched from the beach and there is a 5mph speed limit to reduce noise

Dogs aren't allowed on the middle beach from July to September

Information boards to educate visitors about the environment and how to help protect it 

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Likely Effects of Super Volcano Eruption

 Yellowstone Supervolcano

- 87000 deaths predicted within the area of eruption

- 10,000 km^2 land destroyed

- 15cm of ash covering buildings within 10,000 km

- Ash cloud rising 40-50 km into the atmosphere

- Flights suspended

- Constant snow cover in America and Asia for 3 years

  • Monsoon rains would fail
  • 40% of the population suffering starvation
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Earthquake in MEDC : Kobe Earthquake

- 5:46am on 17th Jan 1995 at Nojima fault line

- Earthquake measuring 7.2 on Richter Scale

  • 6,500 dead
  • 40,000 seriously injured
  • 300,000 homeless
  • Huge damage to buildings (30% of Osaka to Kobe tracks left)
  • Hanshin Expressway destroyed
  • 1 million homes without water for 10 days
  • $220 billion worth of damage

- Responses

  • Emergency services searched for survivors in rubble
  • Hospitals working non-stop
  • Motorola gave telephone connections for free
  • New laws for building of earthquake proof buildings
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Earthquake in LEDC : The Sichuan Earthquake

- 12 May  2008, 2:28pm. Indian Plate collided with the Eurasian Plate along Longmenshan fault line.

-  7.9 on the Richter Scale, tremors lasting 120 seconds

  • 70,000 dead + 20,000 missing
  • 400,000 injured
  • 10 million homeless
  • 80% buildings collapsed due to cheap building materials
  • Lack of communications, limited access by roads due to landslides, and flooding
  • $75 million worth of damage

- Responses

  • 20 helicopters assingned to rescuse survivors
  • Provisions of shelter, water and food
  • £100 million of donations by the Red Cross
  • Debts of survivors written off
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Volcanic Eruption : Mt St Helens

- 8:32am, 18 May 1980

The were signs of an eruption in March 1980, so evacuation had been carried out

  • Magnitude: 5.1
  • Caused the biggest landslide ever recorded
  • All living organisms 27km to the north of volcano wiped out.
  • 57 dead

- Responses

  • Helicopters mobilised for search and rescue
  • Ash was cleared from roads within 3 days
  • Masks provided to locals to aid breathing
  • Housing reconstructed
  • Forest replanted + Road rebuilt
  • Over time, animals like elks returned
  • Much more fertile soils left behind
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Indian Ocean Tsunami

- 26 December 2004, when Indo-Australian Plate subducted beneath the Eurasian Plate

  • The earthquake measured 9.1 on the Richter Scale
  • Highest wave: 25m
  • 220,000 dead ; 650,000 seriously injured ; 2 million homeless

- Responses

  • The vast area affected meant that rescue services could not help everyone
    • Diseases spread and wounds worsened
  • Freshwater + food and shelter provided
  • £372 million donations from the UK
  • Indian Ocean Tsunami Warning System set up in June 2006

- Specific Areas Affected

  • Banda Aceh in Sumatra - people swept away
  • Two-thirds of the Maldives' low lying capital, Male, inundated
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The Andes

 Uses

  • Farming
    • Mountain slopes used for subsidence farming, such as potatoes
    • Terraces used to retain water and make farming easier. Most farming in the lower valleys
    • Using llamas to carry materials for irrigation and for meat, milk and wool
  • Mining
    • Range of important minerals - Tin from Peru and Bolivia; Gold from Peru (Yanacocha goldmine)
    • Provides jobs
  • Hydroelectric Power
    • Steep slopes used to generate hydroelectric power, eg Yuncan project dams the Paucartambo and Huachon rivers
  • Tourism
    • Trails for hiking: Inca Trail; Heritage Sites: Machu Picchu
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Tourism in the Alps: Chamonix

- Located in the north-westerly part of the Alps in France. 100,000 visitors every day 

  • Winter Attractions
    • Skiing + Snowboarding + Ice Climbing + Paragliding
    • Hotels, Restaurants, Heated swimming pools and Museums within Chamonix
  • Summer Attractions
    • Montenvers railway takes visitors to the Mer de Glace (glacier) with ice caves
    • 350km of hiking trails + Boating + Rock Climbing
    • Live music, cafes and flowers within Chamonix
  • Impact of tourists
    • Employment + Improvement of local facilities and town appearance
    • Noisy + Congested at times due to small roads.
    • Erosion of mountain footpaths
    • Shops become expensive for locals
    • Conflicts can arise between tourists and locals.
  • Management
    • Promotion of responsible tourism + Offers eco-friendly transport
    • Espace Mont-Blanc Initiative and Tomorrow's Valley Organisation
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Temperate Deciduous Forest: Epping Forest

- North-east of London; covers 2,500 ha (19km long x 4km wide)

  • Wide variety of environments such as woodland, grasslands and marshes
  • Early Uses and Management
    • Hunting; Collecting wood; Grazing
    • Pollarding; Made a conservation site to prevent people from buying it
  •  
  • Recent Management
    • 1,500 ha designated as an SSSI
    • Provision of facilities for tourists like car parks and toilets to limit damage to the forest
    • Controlling some forms of recreation to limit damage
    • Preserving ancient trees by pollarding (1,000 trees repollarded since 1981)
    • Preserving animals living there
    • Encouraging grazing to maintain soil fertility
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Deforestation of a tropical rainforest: Malaysia

- Located in south-east Asia. 63% of Malaysia is tropical rainforest

  • Dangers
    • 150,000ha of forest lost every year
    • Clear felling of trees leads to total destruction of the rainforest
    • $2bn Bakun Dam project resulted in the flooding of 1000s of hectares of rainforest
      • 250 km^2 of virgin rainforest cut down
      • 9,000 indigenous people forced to move from the area but not supplied with rehousing
    • Areas of rainforest cleared for mining, leading to pollution of land and rivers
    • Drilling has started in Borneo, as well as deforestation for palm oil plantations
    • Land cleared for countryside population
    • Fires are common due to "slash and burn" methods
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Desert in LEDC: Thar Desert, Rajasthan, India

  • Economic Uses
    • Subsidence farming of basic crop, as well as hunters
    • Irrigation and Commercial Farming
      • Indira Gandhi Canal - 650km long - irrigates 3,500 km^2 of land in Jodhpur and Jaisalmer, allowing commercial farming of wheat and provides drinking water to people in the desert
    • Mining Industry
      • Rajasthan has a good supply of kaolin and gypsum
      • At Jaisalmer, the Sanu limestone, the main source of limestone for Indian steelworks
      • Rock marble quarried near Jodhpur
    • Tourism
      • Desert safaris on camels at Jaisalmer.
  • Problems and Management
    • Growing population leads to the destruction of land and ecosystems
    • Salinisation has occurred due to excessive irrigation + Soil erosion due to overgrazing
    • Desert Development Program started to preserve the ecological balance of the desert and stabilising sand dunes
    • The Thar Desert National Park has been created to protect 3,000 km^2 of land
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Desert in MEDC : Sonoran Desert, Arizona, USA

- 300+ mm of rainfall every year

  • Air conditioning is used to deal with heat, preventing the need to convert the land
  • Good water supply can be used for irrigation and drinking supplies
  • Clean air and open spaces allow tourist sites to be built to generate money

- Manara, a town in the Sonoran Desert

  • Population of 30,000
  • In 1920, a new irrigation system allowed the commercial farming of cotton, wheat and barley
  • Since the 1990s, farming has declined and replaced by housing and a heritage park has been opened
  • The town has become a wealthy business community and hosts golf Matchplay Championship
  • Management
    • 1998, Sonoran Desert Conservation Plan initiated to conserve resources
      • Led to the creation of buffer zones of ecological significance
      • Provides home design recommendations to conserve energy and water
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Khumbu Glacier, Nepal

- Starts on the Western corrie on the slopes of Mt. Everest

- The largest glacier in Nepal - 4km long

  • Since 1980, the glaciers have been retreating. The process increased in 1995
  • Between 1976 and 2007, scientists found that the Khumbu glacier retreated by 18m a year

- Melting glaciers causes rivers flowing through Nepal and India can flood

- In 2010, cameras were set up in Mount Everest to monitor glaciers for 2 years.

  • This will allow scientists to plan for the future of Nepal
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Management of Malaysia Rainforest

Management

  • National Forestry Act - banning of sale of raw timer ; timber processing to reduce demand for raw timber; increase awareness of forests
  • Selective Management System - A system in which scientists decide which trees should be felled and in which direction. After felling, the trees are replanted and allowed to grow
  • Permanent Forest Estates - ban commercial activity in virgin rainforest areas
  • Forest Stewardship Council - promotes the purchase of wood from sustailable sources, rather than rare hardwood
  • Ecotourism - allows locals to make a living without damaging the environment
  • Debt Relief - Paying countries to maintain rainforests or cutting their debts in exchange for rainforest maintainence
  • Carbon Sinks - Large forests maintained to reduce CO2 in the air. Eg Gola Forest in Sierra Leone (supported by European Commission and the French government)
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Fragile Environment : Abondance, France

  • The resort has had over 15 years of unreliable snowfall. 
  • People are considering: Developing other forms of winter sports or add summer activities to make the resort availiable all year round.
  • New developments:
    • High Alps are being built on to make more resorts
    • Roads, housing and ski lifts are damaging habitats and the ecosystem
    • Trees are cut down (they bind the soil), which can make avalanches more likely
    • Footpath erosion can leave scars on the landscape.
    • Increasing visual and noise pollution reduces the attractiveness of the resort
  • In Austria, the Gepatsch Glacier is being opened for skiing
  • Cable cars are being used to transport skiers upland
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Keywords- Rivers

Source: start of the river

Meander: is a bend in the river

Floodplain: is an area that is flat and vulnerable to flooding often in the lower section of the river.

Confluence: is the meeting point (or junction) of where two river's meet.

Tributary: is the smaller river that eventually joins the main river.

Drainage basin : is the whole area around where eventually water is drained into the river. Sometimes referred to as the 'Catchment area'.

Watershed: is the boundary line between two drainage basins.

Mouth: when the river joins the end and flows out to sea.

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Case Study : The River Severn

Upper Course: gradient is very steep, bedload size is big, very shallow, channel shape (        ), high velocity (speed), valley shape (        ), waterfall gauge.

Middle Course: gradient is less steep, bedload size is less big, getting deeper, channel shape (     ), less velocity (speed), valley shape (       ), meander ox boe lake.

Lower Course: flat, small bedload size (fine particles), very deep, channel shape (      ), little velocity (speed), valley shape (      ), flood plain.

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Characteristics of how a river changes

      Upstream (source)                                                          Downstream (mouth)

Gradient:    steep                                                                                  flat

Bed load size:   big                                                                               small

Channel depth:   shallow                                                                       deep

Channel width:   narrow                                                                         wide

Human activity:   less                                                                            more

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EXAM STYLE QUESTION

Describe how the shape and characteristics of river channels change form source to mouth.                                                                                                                                        (6 marks)

Near the source of the river (upper course), the river channel will be narrow and shallow, having a big bedload size. Here the gradient is very steep which can result in the river having a high velocity. The middle course of the river the sides are often still quite steep, the bedload size is not as big and the depth of the river increases. the gradient becomes less steep, resulting in the velocity of the river being less fast. Near the mouth of the river (lower course), the river is wider, the floodplain is flat with very gentle sides, the depth of the river increases dramatically. The gradient is gentle, flat causing the velocity of the river to be slow.

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Braking down, transportation and Deposition Of a

1. Erosion: means the wearing away of the landscape.

          - Abrasion: where the sand and pebbles erode the river bank and beds.

          -Attrition: where rocks and stones wear away as they collide into each other.

          -Solution: where rocks are dissolved.

          -Hydraulic action: where fast-flowing water erodes the river banks.

2. Transportation: is the movement of sediment by a river.

         -Suspension: very small bits of soil and rock are carried in the river. 

         -Traction: large rocks dragged and rolled along the river bed.

         -Saltation: smaller stones and pebbles bounce along the river bed.

3. Deposition: is where sediment from a river is dropped as the energy from the river is not sufficient to carry the sediment any further.

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Causes of Floods

Causes of flooding:

-Heavy rainfall: increase in precipitation in a short period of time causes a river to overflow.

-Impermeable rock: when it does rain all the water has nowhere to be absorbed therefore it will build-up resulting in flooding.

-Hard baked soil: this acts as an impermeable rock, causing a major decrease in infiltration but increase in chances of flooding.

-Steep slopes: as the slopes are very steep the water running down it has no time to infiltrate, as there is an increase in surface runoff, the water will build-up at the bottom that could result into flooding.

-Deforestation: there are no trees/plants to intercept (decrease) causing an increase in overland flow.

-Building on floodplains (urbanisation): due to the impermeable rock, water is unable to infiltrate, these increases surface fun off; the water will flow done to the river causing the levels of the river to increase which will result into flooding.

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Flood Hydrographs

Flood hydrographs: they show the relationship between rainfall (precipitation) and how much water is in a river (discharge)

Peak discharge: the highest level of the river

Lag time: the difference between peak discharge ad peak rainfall

Peak rainfall: the highest level of rainfall 

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Case Study : Boscastle, 2004

Boscastle is situated in the North Cornwall Coast, South West of England.

Causes of Boscastle flood:

-6 hours of heavy rainfall, 6 inches of rain

-Buildings on a flood plain (urbanisation)

-Vegetation cleared

-Boscastle is near a confluence

-Saturated round

-Steep-sided hills, increase in surface runoff

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EXAM STYLE QUESTION

For a named location, explain how human actions have increased flood risk.                                                                                                                                           (6 marks)

Two human actions in Boscastle have increased the threat of flooding. Clearing vegetation has increased the rate of surface runoff as less rainfall is being absorbed by the plants and trees as they have been cut down, this results to shorter lag time. There would further be a decrease in an interception as those plants and trees that have been cut down are not able to intercept and absorb the rainfall. Building on a floodplain has also decreased the amount of rainfall being infiltrated into the ground. This is because the water from the rainfall is unable to be infiltrated within the impermeable rock. This causes river levels to increase resulting in flooding, as it has resulted in shorter lag time.

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Impacts on the Boscastle flood

Impacts:

-Lose of jobs

-Damage of possessions

-Lose of stock, pets, business'

-Re-building of houses

-Decrease in tourism

-Damage of cars

-Insurance premiums went up

-Escape was hard

-People lifted to safety

-Flooded houses, ruined furniture

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Responding to the 2004 flood (Boscastle)

In order to prevent flooding in Boscastle again, authorities have:

-Deepened the river channel to allow more water to be stored

-Widened the river to allow more storage of water

-Demolished the old bridge (thick) and built a new thinner one using better materials

-Put in a new drainage system

-Raised car park levels

They spent £4.5million on a new scheme to prevent flooding in the future. 

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Flood management: Hard engineering

Hardengineering: designed to prevent flooding by expensive construction projects e.g. dams, flood walls, channel diversion, increasing channel size                                                                                                                                                                                                                              Type                                           Benefits                                         Problems                

Build flood plains (leeves)         Preventing flooding in                   Expensive, can increase flood                                                 built up areas.                           problems furthur downstream.

Increase the size of the           It allows the river to hold                  Expensive to construct, affects  river channel               more water, reduces flood               wildlife by the river banks.                                                     risks.                                      

Divert the river away              Reduce the risk of flooding in                Very expensive, can cost £14 from the ciry centre          the town centre.                                   million per 1km stretch.

Building dam                         Prevent flooding, produce hydro-          Very expensive, flood area                                         electric power, control           between the dam, takes                                                                  river when flow is low.             time to build/make.

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Soft Engineering

Soft engineering: deisgned to reduce the impacts from flooding. Tries to work with nature rateh the against and realises the importance of natural ecosystems as a way of reducing flooding e.g. afforestation. flood warnings, floodplain zoning.

Type                                    Benefits                                          Problems                          

Flood abatement        Prevents flooding in a                    Takes a long time to plant trees.(afforestation)            natural way & is relatively               This will not have immediate impact.                                       cheap.

Floodplain zoning       It is cheap as it does not                Doesn't protect the existing buildings   (area designed to        require any building of flood          already found in these zones.             flood)                         plain. 

Flood warnings         Helps to save lifes rather than          Doesn't people's property.                                                      to stop flooding.

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EXAM STYLE QUESTION

With reference to a named example, describe the measures that can be taken to prevent the impacts of flooding.                                                                                       (6 marks)

In Boscastle in 2004, there was a devastating flood that caused alot of damage to the village. £4.5 million was spent to prevent future flooding events. Firstlt, authorities have deepened and widened the river channel to allow more water to be stored. So, they have they have re-shaped the river in the way so for it to stop over flowing resulting in flooding. They have further demolished the old bridge into building a new one that is thinner built using better materials. This will allow more water to flow down the river. Raising the car park level will decrease the chance of flodding as the water wont flood the cars as easily. These are all examples of hard engineering as it prevents flooding but also harms the environment. 

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Case Study : Mississippi, USA

The Mississippi River burst its banks in 1993, it is over 3000 km long. It is one of the heaviest hard engineering rivers. Authorities have charged the map of the valleys, built controlled dams along the river, a lot. This caused the river to shorten by 250km. Leeves were made, straightened the river channel, wing dytes narrowed and deepened the river.

Benefits:                                                                                                                             

  • The economy has grown as there is no more flooding
  • created jobs
  • controlled dams generate electricity
  •  Straightening the river made shipping easier.

Problems:

  • Very expensive, $7million
  • 100 years of building it to where it is now
  • Has affected the environment, destroyed animals habitats
  • The river will possibly flood
  • Warm air and cold air collided caused an extreme amount of rainfall which resulted in the leeves to burst.                        
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Case Study : River Rhine, Germany

It is a soft engineering scheme, allowed flood plain zoning (ecological flooding) - a way of flooding in the natural environment. 24 zones were designed to be flooded.

Benefits: 

  • Ecological flooding  
  • Cheap  
  • Creates new wet land, plants, habitats
  • Doesn' harm the environment  
  • Generated hydroelectric power down stream in France

Problems:

  • Creates a conflict between France and Germany
  • Millions of pounds of damage
  • Flooded houses
  • The architecture flood walls is what caused the major flood, as the water built up behind the   walls and was relished all at once.
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EXAM STYLE QUESTION

With reference to named examples, describe the measures that can be taken to prevent the impacts of flooding                                                                               (8 marks)

Flooding of rivers can be managed in two ways; hard engineering or soft engineering. An example of a hard engineering project is the Mississippi river scheme. In this scheme American architects re-created the shape of the river, making it straight. This was a benefit to shipping as it made it easier to trade to transport goods. They further built dams along the river, this prevented flooding as the dams controlled how much water was flowing down the other side. However, this shortened the river by 250km. Lastly, they built wing dytes that narrowed and deepened the river, allowing more water to be stored. 

An example of a soft engineering scheme is the River Rhine scheme in Germany. They prevented flooding by ecological flooding. This allowed new wetland to be formed which evolved new plant and animals. They allowed 24 zones to be flooded which helped prevent flooding in built-up areas i.e cities.

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Hurricane Katrina 2005

  • On the morning of August 29th 2005 a tropical storm formed off the Gulf Coast
  • When it reached the land, it was a category 3 hurricane on the Saffir-Simpson Hurricane Scale with wind speeds between 100-140mph, covering 400 miles
  • There was $100 billion in damage
  • A tropical depression in the Bahamas on August 23rd allowed experts to predict the tropical storm
  • A storm surge 9 metres high caused 80% of the city to be underwater; people climbed to rooftops 
  • 80% of the city was evacuated, 10,000 people sought shelter in Superdome (a stadium in New Orleans)
  • Coast guards saved 34,000 people in the New Orleans alone, and people helped eachother by offering shelter and resources
  • The government was not prepared for a hurricane of this size and had no immediate solutions to the problem
  • 2,000 died and 90,000m2 of land was affected 
  • Money was then put into improving hurricane predictions, the government is still recovering from the disaster 
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Tectonic Hazards:Reducing the risk

Monitoring:

Scientist are constantly monitoring active volcanoes through :Remote sensing using satellites, Seismicity graphs of the earthquakes, Geophysical measurements which detect changes of magma

Prediction:

Volcanoes are based on monitoring and hotspot plate margin areas are identified through history

Protection:

Earth embankments can be used to divert lava from the property. Earthquake resistant building can be made with shock absorbers on the floor and are built with strong materials.

Planning:

Maps have been produced to show the high-risk areas to warn people

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Weather Hazards- Global atmospheric circulation

The movement of air around the earth to balance the temperature 

  • Air sinks and forms areas of high pressure
  • Air rises and forms areas of low pressure
  • Winds move from areas of high pressure to low pressure
  • Surface winds transport heat from one place to another
  • Seasonal changes affect this pattern

Related image        Related image

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How can weather be hazardous?

Weather-->Day to day condition of the atmosphere

Hazardous-->Risky/dangerous

Global Circulation System

Heat transferred from poles, by ocean currents & wind, keeping Earth's temp. balanced.

Air rises at equator-creates low pressure (clouds and rain)

At 30 degrees north and south of equator-air sinks-creates high pressure-HIGH=DRY

At equator-sun's rays=CONCENTRATED-->temperature=very HOT

At poles-sun's rays=less concentrated-->temperature=very COLD

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What causes extreme of temperature?

THE ALBEDO EFFECT: How much surface reflects/absorbs sun's rays. e.g. Polar ice=HIGH albedo-->reflecting heat-keeps poles cold & Rainforest=LOW albedo-->absorbs heat-keeps it hot

CLOUD COVER: At equator=lots of clouds-->prevents full force of sun's rays getting through-keeps warm weather instead of extremely hot. At 30 degrees-no clouds-->full force gets through-extremely hot weather and temperatures.

OCEAN CURRENTS: Ocean currents-move heat easily. London's latitude (distance from the equator) =51 degrees North(Moscow & Winnipeg-Canada)=much colder winters (-10 degrees or below)-warmer summers (20 degrees) than London. UK climate influenced by North Atlantic Drift(warm ocean current)-->makes the UK warmer than expected for its latitude.

DISTANCE FROM SEA: Sea heats up/cools down-slower than land-->places next to sea=milder in summer & warmer in winter.

ALTITUDE: Higher up place is-colder and wetter it is. For every 100m you go up-is 1/2 degree fall in temperature.

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What makes the temperature extreme?

England and Australia have very different 'extreme' temp. England-30 degrees=EXTREME-->average weather for Australia-40 degrees=EXTREME. Both-extreme temp=above 10 degrees above average summer temp. UK-20 degrees & Australia-30 degrees.

HOTTEST PLACE ON EARTH: Lut desert-Iran-70.7 degrees-->place recorded covered by black lava=LOW ALBEDO. No-one lives there-too hot and dry-Nomads & Tourists pass through. Visitors must be careful-bring enough water-protect eyes from sun's rays

COLDEST PLACE ON EARTH: Antarctic-temp as low as -89.2 degrees-->sun's rays hit wide angle-not very concentrated. 98% covered in ice=HIGH ALBEDO-reflects heat. No-one lives there permanently. Tourists & Scientists visit e.g. The British Antarctic Survey research station.

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Extreme Wind

WINDMovement of air from an area of high pressure to low pressure-greater difference in pressure-stronger the wind.

How do we measure wind speed?

An anemometer measures wind by counting a number of rotations per minute-Wind speed measure on Beaufort scale-ranges from 0(calm) to 12(hurricane). The windiest places on Earth

  • Mt Washington-winds up to 372km/hr-->forms barrier to westerly trade winds
  • In Antarctica ice sheets slope into sea-Katabatic winds cause downhill winds blowing 327km/hr
  • Mt Everest reaches jet stream (winds in high atmosphere-very strong as little to slow down)-Wind speeds of 255km/hr-climbers choose May to climb-jet stream moves South them-wind=slower and safer
  • Strongest winds recorded-408km/hr on Barrow Island(Australia) during Hurricane Olivia-1996

TornadoesVery strong rotating winds-smaller than hurricanes-winds reach up to 400km/hr--Tropical Storms=much larger-form over the sea.

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Winds in the UK

Highest wind speeds in UK-recorded on top of mountains-west of country. Strongest gusts=278kph-recorded top of Cairngorm mountains on 20 March 1986. Strong gusts recorded at low levels-along exposed coastal areas-Most recorded wind gusts occurred in winterWinter=windiest time of year in the UK. This time of year-jet streams further south allowing more Atlantic storms to affect the UK.

Localized effects with hills, mountains and coasts being winier than low-lying inland areas.Wind speed increases as you go upwards away from friction caused by Earth's surface.-explains windier coasts as sea surface produce less friction than land.

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Extreme Rainfall

What is precipitation?

When warm air rises, is cooled down and condensation (change from water vapour to water droplets) occurs, forming clouds. Clouds become heavier-until release precipitation which falls as rain, hail, sleet or snow depending on the temp of the atmosphere.

Rain doesn't fall evenly around the world...

Along with a low pressure belt around the equator, rainfall is high. Where high-pressure belt sits at 30 degrees N & S of equator-amount of rainfall=extremely LOW. Coasts of a continents-much wetter. Mountainous regions experience high levels of rainfall.

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Rainfall

CONVECTIONAL RAINFALL:

Sun warms up ground during day-heats air above ground-warm air rises-as air rises it cools & condenses, forming clouds. This type of rain-common at the equator in the afternoon. Summer evening thunderstorms in UK-associated with convectional rainfall.

FRONTAL RAINFALL:

When a band of warm air meets a band of cold air-is called front. Warm air is less dense-rises up over cold(denser) air. As warm air rises it cools and condenses-rain that falls as result-called frontal rainfall. This type of rain-common in UK-polar front-cold air coming down from N pole meets warm air coming up from equator.

RELIEF RAINFALL:

Air forced to rise over mountains-creates low pressure-air rises-cools & condenses forming clouds and rain-when air sinks down another side of mountain-creates high pressure-rainshadow effect. In UK mountains like the Pennines tends to be wetter on their western sides and drier on the east.

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Tropical Storms

The distinction of tropical storms: Hurricanes, cyclones & typhoons=names given to tropical storms-different parts of the world. The form between 5 & 20 degrees N and S of equator-trade winds meet-water is warmer 26.5 degrees & deeper than 60m. A large body of warm water required-for evaporation & condensation to occur quickly enough so the release of latent heat powers storm. Is why tropical storms occur in late summer & early autumn(oceans are warmest). Tropical storms DO NOT  form at the equator as a here-Coriolis effect(spin of the earth) isn't strong enough. Storms measured on Saffir Sampson scale from 1-5 according to strength of winds.

The frequency of tropical storms: has been no increasing trend in no.of tropical storms-Atlantic region seen increased no.since 1995. In future-tropical storms become more intense-stronger wind speeds & heavier precipitation-as global warming means ocean waters will be warmer-faster evaporation=greater power.

Hazards associated with tropical storms:

  • Strong winds
  • Heavy rainfall-floods & landslides
  • Storm surges-very low pressure-raises level of sea-huge waves-flooding, structural damage to buildings, large areas of land uninhabitable for a long period, roads washed away/flooded, damage to ports.
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CASE STUDY:Typhoon Haiyan, Philippines 2013

Causes: Typhoon Haiyan formed in Pacific Ocean-latitude of 7 degrees N of the equator. Sea surface temp-over 26.5 degrees-deeper than 60m. Coriolis effect started storm spinning-storm moved westwards over ocean-gained speed from warm waters. Government-issued warnings-people had nowhere to go-Phillippine warning system has 4 levels-represented by 4 colours. People can find warnings on TV, radio or social media.

CONSEQUENCES:

PRIMARY CONSEQUENCES are those that happen straight away

  • most deadly hazard was storm surge-flooded coastal areas-InTacloban-5.2m high-destroyed 90% of city-including an evacuation shelter-many drowned
  • Strong winds damaged buildings
  • 6300 died-over 1/2 a million left homeless
  • People were killed by falling debris
  • infrastructure(roads, electricity supply etc) were damaged
  • Trees were uprooted & crops were damaged
  • The barge was punctured & 85,000 litres of oil leaked into the sea
  • $2,86 bn damage
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Consequence

SECONDARY CONSEQUENCES are those which occur in the days & weeks following the disaster

  • People forced to live in tents, without clean water or electricity
  • Diseases spread rapidly through the tented settlements
  • Roads were blocked by trees, making hard to travel
  • 77% of farmers and 74% of fishermen lost the main source of income

Why were consequences so great?

Philippines is an EDC (emerging & developing country)-ranked 117th ou of 187 countries in the world for development. 25% of the population live below the poverty line of $1.25 a day. The area hit by the typhoon was still recovering from the Bohol earthquake a month before. 

Typhoon Haiyan crossed densely populated areas. Large no.of people were affected by wind, rain and storm surge. Many of the people lived in poorly constructed houses that offered little protection from the storm.

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Response

EMERGENCY RESPONSES: Short-term aid was a priority.FOOD, WATER, SHELTER etc.

  • 50,000 solar lanterns were given out
  • Australia sent medical staff, materials to build shelters, water containers & hygiene kits
  • Social media hashtags were created to allow survivors to call for rescue or search for missing people

The emergency aid effort faced many difficulties, the Airport was destroyed & was looting and crime.

LONG TERM RESPONSES: Once initial emergency had been tackled, in weeks & month following typhoon the focus turned towards long term aid

  • By April, 107,000 households provided with tools, materials & technical advice to repair homes
  • Seeds and fertilisers were given to help farmers get back on their feet
  • Schemes were set up to pay people to clear away debris, repair infrastructure and replant mangroves(swamps) around the coast to act as a natural buffer against future storms.
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Drought

DROUGHT = less than average rainfall over a specific time

A drought in the UK is very different from drought in Ethiopia. UK=inconvenience--Ethiopia=matter of life or death-drought bring food shortages, starvation and death.

The distribution of drought-What causes drought? Drought is linked to long periods of HIGH air pressure-bringing DRY conditions.

EL NINO: In an El Nino year-water off the coast of South America is warmer than usual-makes air warmer-air rises not sinking-low pressure instead of high-rain and floods. Reversed walker cell off the coast of Australia-air sinking instead of rising-high pressure-dry conditions-brings drought to Australia. El Nino as effects in terms of rainfall throughout the world. As well as Australia-droughts more common in Asia-in El Nino years.

LA NINA years=exaggerated version of a normal year. High pressure off the coast of South America higher than usual-drought in Peru and Chile. Off the coast of Australia-low pressure even lower-flooding.

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Consequences of Drought

The frequency of drought: Pattern of drought around world-changing over time-severity increased since 1940-->changing climate (warmer temp and less rain).

What are the CONSEQUENCES of drought?

  • Shortages of food
  • Shortages of water
  • Bush fires
  • Poor air quality
  • Power cuts-for countries that rely heavily on HEP (hydro-electric power) to produce electricity
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CASE STUDY:THE UK DROUGHT 2012

CAUSES of the drought:

  • Unusual wind patterns brought dry, continental winds from the east rather west (from Atlantic)
  • Temp warmer than usual-more water evaporated from reservoirs and soils dried out
  • The soil was baked hard by sun-impermeable(unable to soak in)
  • Water used inefficiently-treated as never ending-wasted through leak old pipes

CONSEQUENCES of the drought:

  • Farmers struggled-find water for crops & animals
  • Dry areas-moorland-south wales, surrey, Scottish borders-caught fire easily
  • Tarmac melted due to heat
  • More river water used than usual-problems with plants and animals
  • Hosepipe van introduced to 20 million-stopped from watering gardens & washing cars
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Responses to drought

RESPONSES to the drought: Water companies took action to keep water flowing.

  • Permits granted so water could be extracted from rivers and underground aquifers
  • Hosepipe bans issued to conserve remaining water
  • Campaigns launched to encourage people to use less water e.g. taking short showers instead of baths and turning off the tap whilst brushing teeth (saves 6 litres of water per minute)
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What is climate change?

Climate change - any significant change in the Earth's climate over a long period 

The Earth is getting warmer.

  • The Quaternary period (the whole of human history) is the most recent geological time period - from 2.6 million year ago to today. 
  • In the period before the Quaternary, the Earth's climate was warmer and quite stable. Then things changed.
  • During the Quaternary, global temperature has shifted between cold glacial periods that last for around 100,00 years and warmer interglacial periods that last around 100,000 years. 
  • The last glacial period ended around 15,000 years ago. Since then, the climate has been warming.

Global warming - the sharp rise in global temperatures over the last century.

(Type of climate change)

SUMMARY -

During the Quaternary period, the climate repeatedly went from warm to cold and then back to warm again. Now, its getting rapidly warming.

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The evidence

Scientists can work out how the climate has changed over time using a range of methods:

1. Ice and Sediment Cores

  • Ice sheets are made up of layers of ice - one layer is formed each year.
  • Scientists drill into ice sheets to get long cores of ice.
  • By analysing the gases trapped in the layers of ice, they can tell what the temperature was each year.
  • The remains of organisms found in cores taken from ocean sediments can also be analysed. These can extend the temperature record back at least 5 million years.

2. Temperature records

  • Since the 1850s the global temperatures have been measured accurately using thermometers. This gives a reliable short-term record of temperature change.
  • Historical records can extend the record of climate change a bit further back.
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The Evidence

3. Pollen analysis

  • Pollen from plants can be preserved in sediment. 
  • Scientists can identify and date the preserved pollen to show which species were living at the time.
  • Scientists know the conditions plants live in now, so preserved pollen from similar plants show that climate conditions were similar.

4. Tree rings

  • As a tree grows, it forms a new ring each year - the tree rings are thicker in warm, wet conditions.
  • Scientists take cores and count the rings to find out the age of a tree.
  • The thickness of each ring shows what the climate was like.
  • Tree rings are a reliable source of evidence of climate change for the past 10,000 years.
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Natural factors as causes of climate change

1. Orbital changes 

  • The way the Earth moves around the Sun changes. 
  • These changes affect the amount of solar radiation (how much energy) the Earth receives. 
  • If the Earth receives more energy, it gets warmer.

2. Volcanic activity

  • Major volcanic eruptions eject large quantities of material into the atmosphere.
  • Some of these particles reflect the Sun's rays back out to space, so the Earth's surface cools.
  • Volcanoes also release CO2 (a greenhouse gas) but not enough to cause global warming.
  • Volcanic activity may cause short - term changes in climate. 

3. Solar output 

  • The Sun's output of energy is not constant - it changes in short cycles of about 11 years and possibly also in longer cycles of several hundred years.
  • Periods, when solar output is reduced, may cause the Earth's climate to become cooler in some areas.
  • Most scientists think that changes in solar output don't have a major effect on global climate change
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Human activities as causes of climate change

Greenhouse effect - where greenhouse gases, such as CO2 and methane, absorb outgoing heat, so less is lost to space. It is essential for keeping the planet warm.

  • Too much greenhouse gas in the atmosphere - too much energy is trapped and the planet warms up.
  • Humans are increasing the concentration of greenhouse gases by:

1. Burning fossil fuels

  • CO2 is released into the atmosphere when fossil fuels are burnt.

2. Farming 

  • Livestock produces a lot of methane.
  • Rice paddies contribute to global warming because flooded fields emit methane.
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Human activities as causes of climate change

3. Cement production

  • Cement is made from limestone which contains carbon. 
  • When cement is produced, lots of CO2 is released into the atmosphere.

4. Deforestation

  • Plants remove CO2 from the atmosphere and convert it into organic matter using photosynthesis.
  • When trees and plants are chopped down, they stop taking in CO2.
  • CO2 is released into the atmosphere when trees are burnt as fuel/ to make way for agriculture.
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Environmental effects from climate change

Environmental effects 

  • Warmer temperatures are causing glaciers to shrink and ice sheets to melt.
  • Water stored on land as ice returns to the oceans - sea level rise.
  • Sea ice is shrinking - loss of polar habitats.
  • Rising sea levels mean low lying coastal areas will be flooded.
  • Coastal erosion will increase with sea-level rise.
  • Some coastal areas will be submerged - habitats will be lost.
  • Species are declining. E.g, coral reefs.
  • Precipitation patterns are changing - warming is affecting how much rain areas get.
  • The distribution and quantity of some species could change and biodiversity could decrease.
  • Some habitats are being damaged or destroyed due to climate change - species that are specially adapted to these areas may become extinct.
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Human effects from climate change

Effects on people

  • In some places, deaths due to heat have increased - but deaths due to cold have decreased.
  • Some areas could become so hot and dry that they are difficult or impossible to inhabit. 
  • Coastal areas could be lost to the sea - impossible to inhabit. Could lead to migration and overcrowding in other areas.
  • Some areas are struggling to supply enough water for their residents due to problems with water availability caused by changing rainfall patterns. Can lead to political tensions, especially where rivers cross borders.
  • Climate change is affecting farming. 

- Some crops have suffered.

- Some farmers in high-latitude countries are finding that crops benefit from warmer conditions.

  • Lower crop yields - could increase malnutrition, ill-health and death from starvation, particularly in lower latitudes.
  • Climate change means the weather is becoming more extreme - more money needs to be spent on predicting extreme weather events, reducing their impacts and rebuilding after them.
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Managing climate change - Mitigation

There are strategies to aim to reduce the causes of climate change by reducing the concentration of greenhouse gases in the atmosphere. 

1. Carbon Capture 

  • A new technology designed to reduce climate change by reducing emissions from fossil fuel burning power stations. 
  • Involves capturing CO2 and transporting it to places where it can be stored safetly. E.g, underground.

2. Planting trees

  • Increases the amount of carbon dioxide that is absorbed from the atmosphere through photosynthesis. 
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Managing climate change - Mitigation

3. Alternative Energy Production

  • Replacing fossil fuels with nuclear power and renewable energy - reducing greenhouse gas emissions from power stations. E.g, wind farms, nuclear power plants.

4. International Agreements 

  • Countries agree to monitor and cut greenhouse gases emissions by signing an international agreement - targets.
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Managing climate change - Adaptation

There are some ways that people are adapting to the effects of climate change.

1. Changing Agricultural Systems

  • Changing rainfall patterns and higher temperatures will affect the productivity of existing systems.
  • It may be necessary to plant new crop types that are more suitable to the new climate conditions.
  • In some regions, biotechnology is being used to create new crop varieties which are more resistant to extreme weather events.

2. Managing water supply

  • Dry areas are predicted to get drier, leading to water shortages.
  • Water meters can be installed in people's home to discourage them from using a lot of water.
  • Rainwater can be collected and waste water can be recycled to make more water available.

3. Coping with rising sea levels

  • Physical defences - such as flood barriers - are being built.
  • Better flood warning systems are being put in place.
  • In areas that cannot afford expensive flood defences, people are building their homes on top of earth embankments and building raised flood shelters to use in emergencies.
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Managing climate change - Adaptation

There are some ways that people are adapting to the effects of climate change.

1. Changing Agricultural Systems

  • Changing rainfall patterns and higher temperatures will affect the productivity of existing systems.
  • It may be necessary to plant new crop types that are more suitable to the new climate conditions.
  • In some regions, biotechnology is being used to create new crop varieties which are more resistant to extreme weather events.

2. Managing water supply

  • Dry areas are predicted to get drier, leading to water shortages.
  • Water meters can be installed in people's home to discourage them from using a lot of water.
  • Rainwater can be collected and waste water can be recycled to make more water available.

3. Coping with rising sea levels

  • Physical defences - such as flood barriers - are being built.
  • Better flood warning systems are being put in place.
  • In areas that cannot afford expensive flood defences, people are building their homes on top of earth embankments and building raised flood shelters to use in emergencies.
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Ecosystems

An ecosystem is a community of plants and animals which interact with each other and their physical environment

Biotic- Living features of an ecosystem eg. the plants/fish

Abiotic- Non-living features of an ecosystem eg. the climate

Producer: Converts energy from the environment (sun) into sugars (glucose) eg. photosynthesis in plants

Consumer: Gets their energy from the producers

Decomposers: Breaks down animal and plant material into nutrients in the soil

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Ecosystems - Fresh Pond Water

Pond bottom:

  • Little light or oxygen, decomposers live here eg, water worms                                           

Midwater:

  • Fish are the main predators here and breathe through gills

Pond surface:

  • Lots of light and oxygen here and some animals here breathe through lungs     

Above pond:

  • Mainly birds live here and get their food from the pond surface

Pond margin:

  • Lots of light, oxygen and shelter here, plants are eaten by small animals on bottom:
    • Little light or oxygen, decomposers live here eg, water worms                                           

    Midwater:

    • Fish are the main predators here and breathe through gills

    Pond surface:

    • Lots of light and oxygen here and some animals here breathe through lungs     

    Above pond:

    • Mainly birds live here and get their food from the pond surface

    Pond margin:

    • Lots of light, oxygen and shelter here, plants are eaten by small animals
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Ecosystems - What Causes Change

Flooding is a physical problem and destroys habitats and affects the food chain

Draining ponds for farming affects fish and aquatic life and destroys habitats

Droughts dry up the soil and nutrients so primary consumers struggle to live

Pollution in ponds breaks down algae/producers and affects other species

Fertilizers can increase the nitrate which increases the growth of producers so oxygen levels decrease and fish may die - eutrophication

Climate change cannot provide suitable for conditions for producers growth so they struggle to grow and affects the rest of the food chain

Fires can burn and destroy small species and habitats which affects the rest of the food chain

Fish stocking can wipe out entire fish species and affects rest of food chain

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Ecosystems- Nutrients cycling

When plants or animals diedecomposers recycle them into nutrients for other plants and animals. The decomposers do not eat the waste but digest them by releasing enzymes which break them down and passes the nutrients into the soil. The plants then absorb the nutrients and the primary consumer gets it. 

Image result for nutrients cycle bbc bitesize

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Ecosystems- Global Biomes

Deciduous- medium temperature- North of the equator

Temperate grassland- hot summer/cold winter- North/South of the equator

Coniferous forest- short summer- North of the equator

Tundra- Frozen- Arctic

Tropical rainforests-Hot/wet- South of the equator

Savannah Grassland-grassy-South of the equator

Mediterranean- hot/dry- Middle North of the equator

Desert-Hot- On the equator

                                                                                                              Image result for biomes bbc bitesize

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Tropical Rainforest - Characteristics

Emergent Layer: Only a few trees and leaves are waxy to prevent drying eg. a monkey would live here

Canopy: The trees knit together and form a dense canopy blocking out the sun and intercepting the rainfall eg. birds, monkeys

Understory: Low light, plants adapt to grow here- dense vegetation along the rivers eg. bird

Shrub layer: Only little light so plants grow slowly, covered in fall leaves and rotting branches- when trees fall, the light gets in and encourages younger plants to grow eg. frogs, snake

Soil layer: Thin and poor and is only a shallow layer, infertile but is nutrients rich eg. insect

Image result for tropical rainforest layers bbc bitesize

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Tropical Rain-forests- Adaptations

Animals:

Gorillas- They have fur to keep them warm and protects against insects

Toucans- Have long becks to reach fruit off trees and cut the fruit off trees

Sloths- Hangs from trees and moves slowly to stay camouflaged 

Plants:

Bark- Thin and smooth so water can flow off it easily

Leaves drip tip- Allows rain to drink of them, also waxy to encourage this

Buttresses- Ridges to support the base of the tree and large surface area for photosynthesis

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