AQA GCSE GEOGRAPHY REVISION Paper 1: Living with the Physical
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AQA GCSE GEOGRAPHY REVISION Paper 1: Living with the physical environment (1hr 30mins) The Challenge of Natural Hazards – Natural hazards, Tectonic hazards, Weather hazards and Climate change The Living World – Ecosystems, Tropical Rainforests and Hot deserts NOT COLD ENVIRONMENTS Physical Landscapes in the UK – UK landscapes, River Landscapes and Coastal Landscapes NOT GLACIAL LANDSCAPES Unit 1: Challenges in the Physical Environment – Natural Hazards PLC Spec Key Idea Theme Red Amber Green 1. Natural Hazards Natural hazards pose What are natural hazards? major risks to people and Name the different types of hazard property What is hazard risk? 2. Tectonic Hazards Earthquakes and volcanic Distribution of earthquakes and volcanoes – are eruptions are the result of there any patterns? physical processes Physical processes at plate margins – constructive, destructive and conservative The effects of, and The effects of earthquakes – Nepal and Italy responses to, tectonic case studies hazards vary between areas of contrasting levels Responses to earthquakes – Nepal and Italy of wealth case studies Management can reduce Living with the risk from tectonic hazards – the effects of tectonic include examples of places living with the risk hazards Reducing the risk from tectonic hazards – monitoring, prediction, protection and planning 3. Weather Hazards Global atmospheric Global atmospheric circulation model – How circulation helps to does it work? How does it affect the world’s determine patterns of weather? Give examples. weather and climate Tropical storms What is a tropical storm? (hurricanes, cyclones, Where and how are tropical storms formed? typhoons) develop as a result of particular physical The structure and the features of tropical storms, conditions including frequency, distribution and intensity. Tropical storms have Typhoon Haiyan – Primary and secondary significant effects on effects, Immediate and long-term responses. people and the Reducing the effects of tropical storms – environment monitoring, protection, planning and prediction The UK is affected by a Weather hazards in the UK – extreme weather – number of weather thunderstorms, prolonged rainfall, hazards drought/extreme heat, heavy snow/extreme cold and strong winds. Extreme weather events in Beast from the East cause and effects – social, the UK have impacts on economic and environmental human activity Beast from the East responses Extreme weather in the UK – is it going to get worse? 4. Climate Change Climate change is the What is the evidence for climate change? result of natural and What are the natural causes of climate human factors, and a change? range of effects What are the human causes of climate change? Managing climate Managing the impacts of climate change - change involves both mitigation mitigation (reducing Managing the impacts of climate change - causes) and adaptation adaptation (responding to change) Definition of a natural hazard. A natural hazard is a natural event which could cause death, injury or disruption to humans or destroy property and possessions. Types of natural hazard. The Hazard can be … Geological Hazards, these hazards can be split up in to two types; those that occur inside the earth (tectonic/geophysical) processes e.g. earthquakes and volcanoes and those occurring on the Earth’s surface (geomorphic) processes e.g. landslides and avalanches. Hydrological Hazards, this is where there is either a harmful change in quality of earth's water or in the distribution or movement of water e.g. (avalanches and floods), Climatological Hazards, this is where there are changes in the earth’s climate e.g. extreme temperatures (hot or cold), drought and wildfires. Meteorological / Atmospheric Hazards, this is caused by extreme “one off” weather conditions e.g. cyclones and storms/wave surges. Biological Hazards, this is where living organisms are affected e.g. disease epidemics and forest fires Factors affecting hazard risk. Natural disasters frequently occur across the world, affecting both High Income Country (HIC) and Low Income Country (LIC). However some populations are clearly more vulnerable than others. Different communities and countries are more susceptible to the impact of these hazards especially those in LICs. Vulnerability Poorer housing quality in LICs which causes higher death tolls, when the buildings collapse. LICs have a poor economy so residents often have risky jobs in areas prone to natural events. E.g. mining sulphur on volcanoes, farming on floodplains. Increasing urban populations where natural events occur. The more people the higher the death toll. Capacity to cope In HICs there are high quality buildings, using strong building materials and designs. E.g. Earthquake proof buildings. In HICs residents of areas prone to natural hazards have, better education, trained search and rescue teams, action and evacuation plans. In HICs more money is spent on technology to predict and protect the residents of the country. E.g. In Japan, locals have texts warning them of approaching tsunamis. Nature of the Natural Hazard Duration: The length of time that a hazard lasts for. As a general rule the longer the hazard the more severe it is likely to be. Regularity: If hazards happen often and in quick succession e.g. a earthquake followed by multiple aftershocks then the severity is likely to be greater. Predictability: Some hazards are easier to predict than others. Generally speaking hazards that hit with no warning are going to be more serious. Magnitude: This is the strength of a hazard. Most hazards are measured on a scale. Generally speaking, the stronger the hazard the more severe the hazard is. Tectonic Hazards - Plate tectonics theory. The Earth is made up of 4 layers. The crust, the mantle, the outer core and the inner core. The crust and the upper mantle form the lithosphere. The lithosphere is broken into several major fragments called tectonic plates, which either form the continents or the ocean floors. Continental crust (lithosphere) Land on top Thick (30 – 100km) Light in weight Made of granite Flexible Will not subduct (Continental uplift.) Older in age (3.8 billion years) Oceanic crust (lithosphere) Covered by ocean Thin (5 – 10km) Dense (heavy) Made of basalt Can be made to subduct. (Sunk and melted into the mantle.) Younger in age (200 million years) Global distribution of earthquakes and volcanic eruptions and their relationship to plate margins. Each plate has a different name. The plates move in different directions; some move towards each other, some alongside each other and some away from each other. Where plates meet it is called a plate boundary/margin. Convection currents occur when the core heats the mantle. This creates a convection current in the mantle. The current drags the plates very slowly moving them at the about the same speed finger nails grow. A ridge push occurs when the weight of an elevated ridge pushes an oceanic plate towards a subduction zone. A slab pull occurs as the weight of the subducting plate pulls the rest of the crust (lithosphere) into the subduction zone. Physical processes taking place at different types of plate margin (constructive, destructive and conservative) that lead to earthquakes and volcanic activity. There are 3 different Plate Margins. Constructive - When 2 plates move apart. Magma forces its way to the surface and as it breaks through the overlying crust it causes earthquakes. The magma is very hot and fluid. It will flow a long way before cooling, resulting in a shield volcano. E.g. North American and Eurasian Plates forming Iceland in the Atlantic Ocean. Destructive - Where 2 plates move towards each other (this can be either an oceanic plate or continental plate moving towards each other or two continental plates which collide). Where an oceanic and a continental plate meets the denser oceanic plate subducts beneath the less dense continental plate. (It also pulls the tip on the continental plate down too, forming a deep ocean trench.) Friction between the plates causes strong earthquakes. As the oceanic plate enters the mantle it starts to melt, which creates more magma. The eruption are violent and explosive due to the steam which is built up from the ocean water. Steep sided volcanoes called composite volcanoes are formed here. E.g. Pacific Oceanic Plate dipping under the South American Continental Plate. Conservative - When 2 plates move alongside each other. Friction between the plates builds up and can cause severe earthquakes. E.g. San Andreas Fault. The effects of, and responses to, a tectonic hazard vary between areas of contrasting levels of wealth. Primary and secondary effects of a tectonic hazard - earthquakes. Primary effects of an earthquake are the immediate impacts of the ground shaking e.g. buildings and bridges collapsing, homes destroyed, people injured or killed by collapsed buildings or debris, transport networks are damaged, power, water and communication networks cut off. Secondary effects are what happen later on, often as a result of the primary effects e.g. earthquakes can trigger landslides and tsunamis, leaking gas pipes can result in fires, people are left homeless and could die from extreme weather conditions, shortage of clean water and poor sanitation can lead to disease, destroyed transport networks results in difficulties getting emergency vehicles in and trade, businesses destroyed which results in loss of income. Immediate and long-term responses to a tectonic hazard. Immediate responses are to stop