GEOG PAPER 1

• How are oxbow lakes formed?

  1. Erosion of the outer bank forms a river cliff: deposition causes the inner bank to form a slip off slop

  2. Further hydraulic action and abrasion of outer banks causes the neck to get smaller

  3. Erosion breaks through the neck, so the river takes the fastest route, redirecting the route

  4. Evaporation and deposition cut off main channel leaving an oxbow lake
• How does a waterfall form?

  1. The river flows over alternative types of rock

  2. The river erodes soft rock faster creating a step

  3. Further hydraulic action and abrasion from a plunge pool beneath

  4. Hard rock above is undercut leaving cap rock which collapses providing more material for erosion.

  5. Waterfall retreats leaving a steep sided gorge.
• How does a coastal spit form

  1. Swash moves up the beach at n angle of the prevailing wind

  2. Backwash moves down the beach at 90 degrees to the coastline due to gravity

  3. A Zigzag movement transports material along the beach

  4. Depositions causes the extended, until reaching an estuary

  5. Change in prevailing wind direction forms a hook

  6. Sheltered areas behind spit encourages deposition. Spit forms
• How are floodplains and levees formed?

  When a river floods, fine silt/ alluvium is deposited on the valley floor. closer to the rivers banks, the heavier materials build up to form natural levees
• How is the upper course of a river formed?

  Near the source, the river flows over a steep gradient from the hill. This give the river a lot of energy so it will erode the river bed vertically to form narrow valley
• How is the middle course of a river formed?

  The gradient gets gentler, so the water has less energy and moves more slowly. The river will begin to erode more laterally making the river wider.
• How is the lower course of a river formed?

  Near the rivers mouth, the river widens further and becomes flatter. Material transported is deposited here.
• Hard engineering - Groynes


  Wood barriers to prevent longshore drift, so the beach can build up. A positive is that the beach is still accessible, But nothing can be deposited further down the coast, which means that it erodes faster.
• Hard Engineering - Sea Wall


  Concrete walls break up the energy of the wave, it has a lip to stop the waves going over. A positive to this is that the beach is still accessible, but the curved shape encourages erosion of sea deposits.
• Hard engineering - Gabions


  Cages of Rocks, Absorbs the wave energy, protects the cliff behind. a positive is that cheap local material can be used to make it look less strange. But will need replacing
• Soft Engineering - Beach Nourishment

  Beaches built up with sand, so the waves will have to travel further before eroding the cliff. A positive to this is that it is cheap and creates a beach for tourists. But when storms happen it will need to be replaced again, offshore dredging also damages the sea bed
• Soft Engineering - Managed Retreat

  Low Value areas of the coast that are left to flood and erode. A positive to this is that it reduced flood rick and creates wild life for habitats. But compensation for land can be expensive.
• Formation of Bays and Headlands

  1. Waves attack the coastline

  2. Softer rock is eroded by the sea quicker forming a bay, calm areas causes deposition

  3. More resistant rock is left jutting out into the sea. This is a headland and is now more vulnerable to erosion
• Types of erosion - The breakdown of transportation of rocks

  Attrition - Rocks that brush together to become smaller

  Solution - A chemical reaction that dissolves rocks

  Abrasion - Rocks hurled at the base of the cliff to break pieces apart.

  Hydraulic Action - The water enters cracks on the cliff, air compresses, causing the crack to expand.
• Types of Transportation - A natural process by which eroded material is carried

  Solution - Materials dissolve in the water and are carried along

  Suspension - Sediment is carried along in the flow of the water

  Saltation - Pebbles that bounce along the sea/river bed

  Traction - Boulders that roll along the river/ sea bed by the force of the flowing water
• Sustainability for the rainforest

  Agroforestry - Growing trees and crops at the same time. It prevents soil erosion and the crops benefit from the nutrients

  Selective Logging - trees are only felled when the reach a particular height

  Education - Ensuring those people understand the consequences of deforestation

  Afforestation - If the trees are cut down, they are replaced.

  Forest reserves - Areas protected from exploitation

  Ecotourism - Tourism that promotes the environment and conservation
• What are causes of deforestation?

  Logging

  Most widely reported cause of destruction to biodiversity

  Timber is harvested is create commercials items such as furniture and paper

  Violent confrontations between indigenous tribes and logging companies.

  
  

  Mineral Extraction

  Precious metals are found in the rainforest

  Areas mined can still experience soil and water contamination

  
  

  Energy Development

  High rainfall creates ideal conditions for hydroelectric power

  
  

  Tourism

  Mass tourism is resulting in the building of hotels in extremely venerable areas

  Leads to a negative relationship between the government and indigenous tribes

  Tourism has exposed animals to human diseases
• Layers of a rainforest

  Emergent Layer - Highest with trees reaching 50 meters

  Canopy Layer - Most life is found in this layer, this is because it receives 70% of sunlight and 80% of life

  U-Canopy Layer - Consists of trees that reach up to 20 meters high

  Shrub Layer - Lowest layer with small trees that have adapted to living in the shade.
• UK Ecosystem - Epping Forest


  It is a typical English lowland deciduous woodland. 70% of this areas is designated as a site of specific interest for its biological interest, with 66% designated as a special area of concentration
• UK Ecosystem - Epping Forest Management

  - Epping forest has been managed for centuries

  - Currently now used for recreation and conservation

  - Visitors pick fruit and berries, helping disperse seeds

  - Trees are cut down to encourage new growth for timber
• Interdependence in te rainforest

  A rainforest works through interdependence. This is where the pants and animals depend on each other for survival. If one component changes, there can be a serious knock up effect for the entire ecosystem.
• Nutrient Cycle

  
• Food web and chains

  
• Abiotic and Biotic


  Abiotic - Non-Living, such as air and water

  Biotic - Living, such as plants and animals
• Evidence of Natural Climate Change

  Orbital Change - Some argue that climate change is linked to how the earth orbits the sun, and the way it wobbles and tilts.

  Sun spots - Dark spots by the sun are called sun-spots. They increase the amount of the energy the earth receives from the sun

  Volcanic Eruptions - Volcanoes release large amounts of dust containing gasses, which can block sunlight. which result in cooler temperatures.
• Managing Climate Change


  Carbon capture - Involves new technology designed to reduce climate change

  Planting Trees - Increases the amount of carbon that is absorbed from the atmosphere

  International Agreements - Counties aim to cut admissions by singing international deals and by setting targets.

  Renewable Energy - Replacing fossil fuels bases energy with renewables eg - COP26
• Recent Evidence for Climate Change

  Global Temperature - Average temperatures have increased by more than 0.6c since 1950

  Ice Sheets & Glaciers - Many of the worlds glaciers and ice sheets are melting

  Sea Level Change - Average sea levels have risen 10-20cm in the past 100 years. This is due to the additional water from Ice and thermal expansion.
• Primary Effects of a tropical Storm

  - The intense wins of a tropical storm can destroy whole communities, buildings and communication networks

  - As well as their own destructive energy the winds can generate abnormally high waves called storm surges

  - Sometimes the most destructive element of a storm are the subsequent high seas and flooding they cause the coastal areas.
• Secondary Effects of a tropical storm

  - People are left homeless, which can cause distress, poverty and Ill health due to the lack of shelter

  - Shortage go clean water and lack of proper sanitation makes it easier for diseases to spread

  - Shortage of foods as crops are damaged.
• Changing Pattern of tropical storm

  Scientists relive that global warming is having an impact on the frequency and the strength of tropical storms. This may be due to an increase in ocean temperatures.
• Management of tropical storms

  Protection - Preparing for a tropical storm may involve construction projects that will improve protection

  Aid- Involves assessing after a storm, normally in LICs

  Education - Teaching people about what to do in a tropical storm

  Planning - Involves getting people and the emergency services ready to deal with impacts

  Development - The scale of the impacts depend on weather the country has the resources to cope with the storm
• Formation of Tropical Storm

  1. The sea is heated to 27c from the suns rays during the summer, which causes moist, warm air to rise over particular spots

  2. Once the temperature is 27c, the rising warm are leads to low pressure, which eventually turns into a thunderstorm and causes the air to be sucked in from the trade winds

  3. With the trade winds blowing in the opposite direction and the rotation of the earth involved, the thunder storm will start to spin

  4. When the storm starts to spin faster than 74mph it is classed as a tropical storm

  5. With the tropical storm growing in power, More cool air sinks in the middle of the storm creating a calm, clear condition in the middle called the eye of the storm

  6. Once the tropical storm reaches land it looses its energy source and begins to lose strength.
• Low and High Pressure differences

  Low Pressure - Cause by hot air rising, causes stormy, cloudy weather

  High Pressure - Caused by col air sinking, causes calm and clear weather.
• Global Atmospheric Circulation


  Hadley Cell - Largest cell, which extends from the equator to between 30 and 60 north and south

  Ferrel Cell - Middle cell where air flows poleward between 60 and 70 latitude

  Polar Cell - Smallest an weakest cell that occurs from the poles to the ferrel cell.

  
• Managing Volcanic Eruptions - Warning Signs

  Small earthquakes are caused when magma rises up

  Temperatures around the volcano rise as activity increases

  When a volcano is close to erupting, it starts to release gasses
• Managing volcanic eruptions - Monitoring Techniques


  Seisometers are used to detect earthquakes

  Thermal imaging and satellite cameras can be used to detect heat around a volcano

  Gas samples may be taken and chemical sensors used to measure sulphur levels
• Managing Volcanic eruptions - Preparation

  Creating an exclusions zone around the volcano

  Having an emergency supply of basic provisions like food

  Being ready and able to evacuate residents

  Trained emergency services and a good communication system.
• Volcanic Hazards


  Ash Clouds - Small pieces of pulverised rock and glass which are thrown into the atmosphere

  Gas - Sulphur Dioxide, water vapour and carbon dioxide come out of the volcano

  Lahar - A volcanic mudflow which usually runs down a valley side on the volcano

  Pyroclastic Flow - A fast moving current of superheated gas and ash (1000c) and travel at 450c

  Volcanic Bomb - A thick lava fragment that is ejected from the volcano-
• Earthquake


  Cause when two plates become locked causing friction to build up from this stress, the pressure will eventually be released, triggering the plates to move into a new position. This movement causes energy in the form of seismic waves, to travel from the focus towards the epicentre. As a result, the crust vibrates triggering an earthquake.
• Earthquake predicting


  - Satellite surveys (tracks changes in the earth surface)

  - Laser Reflector (Surveys movement across the fault line)

  - Seismometer

  - Water table level (water levels fluctuate before an earthquake)

  - Scientists also use seismic records to predict when the next record will occur