geography paper 1

• volcanoes and earthquakes are mostly found on plate margins because the friction and attraction of plates create enormous pressure and stresses which build up to breaking point
• convection currents are a cycle of rising hot material and sinking cold material which occur within the molten rock in the mantle and drive the movement of tectonic plates
• hot spots are places where magma rises up through the crust and are caused by a static source of magma
• Haiti earthquake

  • 12th january 2010
  • 7.0 magnitude
  • primary effects: 220,000 deaths, 300,000 serious injuries , 1.3 million displaced , 100,000 homes destroyed
  • secondary effects: 2 million left without food and water , cholera outbreaks
  • immediate responses: took at least 5 days for aid to reach people - stuck at the airport , military support mostly focused on law enforcement not rescue
  • long-term responses: new communities built a long way from Port-au-Prince , giant tented cities were built within Port-au-Prince but of poor quality
• Christchurch earthquake - feb 2011 - 6.3 magnitude

  • primary effects: 185 deaths , 164 serious injuries , major damage occurred but most buildings remained standing
  • secondary: no clean water or toilets available in much of the city, food shortages were common
  • immediate responses: people were rescued within 20 mins , pre planned aid from neighbouring countries arrived the next morning
  • long-term responses: 10,000 buildings demolished as deemed unsafe , water pipes and sewage systems repaired
• people live near a tectonic hazard because: volcanoes bring benefits such as fertile soils which allow megafarms to be built at the foot of volcanoes e.g. massive farms near mount Etna. Also, geothermal energy can be generated and it generates 25% of Iceland's electricity. Furthermore, plate margins often coincide with favourable areas for settlement and trade such as flat coastal areas
• MPPP strategies for a volcano

  monitoring: remote sensing - satellites detect heat increases and seismographs record microearthquakes

  Prediction: monitoring is used to allow accurate prediction and effective evacuation

  Protection: earth embankments and explosives to divert lava flows

  Planning: risk assessment and hazard mapping
• MPPP strategies for an earthquake

  m: seismographs record microearthquakes before the main tremor and raised water levels are monitored to signify the bulging of the ground

  prediction: accurate predictions are impossible due to a lack of clear warning signs but historical records determine probability

  protection: earthquake resistant construction

  planning: risk assessment, hazard mapping and drills
• sinking air creates high pressure which leads to sunny and clear skies
• rising air creates low pressure which leads to wet and cloudy weather
• rainforests are found on the equatorial low because low pressure marks where the sun is directly overhead. Hot humid air rises, cools and condenses leading to heavy rain
• Deserts are found on the sub-tropical high because high pressure means little rain , hot daytime temperatures and cold nights
• the UK is 60 degrees north which is close to where cold polar air from the north meets warm sub-tropical air from the south. These surface winds from the south west usually bring warm and wet weather as rising air cools and then condenses which forms clouds and rain as a result
• Tropical storms form 5-15 degrees north and south of the equator in summer and autumn where ocean temps are above 27 degrees celsius , the coriolis effect is very high and there is intense heat and humidity which makes the air unstable
• evidence that suggests climate change is occurring: melting ice caps adds fresh water and also causes thermal expansion leading to a rise in sea level. Seasonal changes - trees flowering and bird migration is advancing. Birds are nesting earlier than in the 1970s
• how do the milankovitch cycles cause cooling or warming of the earth?

  eccentricity = every 100000 years on average the orbit changes to elliptical from circular and back again which cools the earth as it is further away from the sun

  axial tilt = every 41000 years the tilt of the earth's axis moves back and forth between 21.5 and 24.5 degrees

  precession= over a period of around 26000 yrs the axis wobbles from one side to another
• what is an ecosystem?

  a complex natural system made up of plants animals and the environment
• producers convert light energy from the sun by photosynthesis into carbohydrates for growth whereas consumers get their energy from eating producers
• a food web is a complex hierarchy of plants and animals relying on each other for food whereas a food chain is individual connections between organisms which rely upon one another as their source of food
• nutrient cycling


  dead plant and animal matter is broken down by decomposers. Minerals and other nutrients are released into the soil which promotes plant growth as the nutrients are used by plants for growth.
• rapid natural changes have severe impacts whereas slow natural changes do not have harmful effects - extreme weather events can be devastating to freshwater ponds
• the removal of hedgerows destroys habitats which effects the plant to animal balance. the use of agricultural fertilisers can lead to eutrophication , nitrates cause excessive growth of algae in the water so the amount of oxygen decreases and fish may die
• Avington Park lake was de-silted an reshaped in 2014 , created new habitats to attract nesting birds and waterfowl , now an ecosystem which supports a diverse range of wildlife
• the climate and characteristics of ecosystems are determined by global atmospheric circulation
• variations occur in east to west belts due to factors like ocean currents, winds and the distribution of land and sea which create small changes in temperature and moisture which affect ecosystems
• Tundra biome

  • located between the arctic circle to about 60-70 degrees North
  • cold, windy and dry conditions which support low growing plants
• Mediterranean biome

  hot , sunny and dry summers , mild winters
• temperate grasslands are located 30-40 degrees North and South of the equator , always inland , warm and dry summers , cold winters

  tropical grasslands are located 15-30 degrees north and south of the equator. distinct wet and dry seasons
• tropical rainforest biome: high temperatures and heavy rainfall , cover 6% of earths land surface
• desert biome: covers 5% of earths land surface, high daytime temps, low night time temperatures, very low rainfall
• tropical rainforests are mostly located along the equator and on the tropic of cancer
• polar biome is most prohibitive and tropical rainforest biome is most diverse
• 50% of the earth's living organisms are found in tropical rainforests. estimated 3-50 million different species
• rainforests are infertile because nutrient cycling is so rapid and nutrients are washed away quickly out of the soil due to heavy rainfall
• deforestation leaves to rainforests prone to leaching since the soil has no cover from the trees , they are exposed
• emergent trees are in the top canopy (30-50m), are hardly exposed, have straight branchless trunks, receive the most light
• the shrub layer is only 0-10m high so there is a lack of light for photosynthesis and growth so vegetation is limited
• lianas are woody vines which have roots in the ground but climb up the trees and their leaves and flowers grow in the canopy to reach the sunlight
• drip tips are pointy tips on the leaves which help them shed water quickly and efficiently so the water can get to the soil and roots faster. Also used to stop heavy rainfall from damaging the plant
• buttress roots are a large root system above the ground. They are spread out wide and deep so they can absorb more water and nutrients. They compete with other plants for nutrients by spreading out into the soil which other plants would use