Geo-

• Natural Hazard


  A natural hazard is a natural process which could cause death, injury or disruption to humans, or destroy proprty or posesions.
• Natural disaster


  A natural hazard that has actually happened
• Geological hazards


  Caused by tectonic processes
• Meteorological hazards


  Caused by weather and climate
• Factors affecting hazard risk

  Urbanisation, poverty, development, climate change
• Tectonic plates


  Slabs of the Earth's crust
• Continental crust


  thicker and less dense
• Oceanic crust


  thinner and more dense
• Tectonic plate movement


  caused by convection currents underneath the Earth's crust
• Destructive plate


  Two plates moving towards one another, oceanic plate subducts under continental plate and friction causes melting of oceanic plate, triggers earthquake

  
• Constructive plates


  Two plates pull away from eachother forcing magma up and causes earthquakes when the magma cools volcanoes form

  
• Conservative plate


  
  

  Two plates moving past eachother at different speeds, the friction creates pressure which when released the plates jolt sending shockwaves which cause an earthquake

  
• Earthquake causes


  two plates 'jerking' past each other
• the focus


  the point in the Earth the earthquake starts
• Epicentre


  the point on the Earth' surface straight above the focus
• Where are volcanoes found

  At destructive and constructive plate margins
• Where are earthquakes found

  At all three types of plate margin
• Earthquake Primary effects


  buildings and bridges collapse

  people are injured or killed

  Roads are destroyed
• Earthquake Secondary effects

  Can trigger landslides, tsunamis = destruction

  homeless

  Disease outbreak

  Leaking gas can start fires
• Earthquake Long term responses

  Re-house people who have lost their homes

  Repair or rebuild damaged buildings, roads, railways and bridges.

  Reconnect broken electricity, water, gas, communication connections
• Volcanoes Primary effects


  Buildings and roads are destroyed by lava flows and pyroclastic flows.

  Buildings may also collapse if enough ash falls onto them.

  People & animals are injured/killed by pyroclastic flows, lava,falling rocks
• Volcanoes Immediate responses

  Evacuate people before if it was predicted

  Provide temporary supplies e.g. electricity, gas and communication systems if regular supplies have been damaged

  Foreign governments or charities may send aid workers supplies equipment or financial donations to areas affected
• Volcanoes Long term responses


  Repair and rebuild if possible or resettle affected people elsewhere.

  Repair and reconnect damaged infrastructure (roads, rail, power lines and communication networks etc)

  Improve, repair and update monitoring / evacuation plans
• Why people live near tectonic hazards

  Attachment to Area

  They are employed in the area.

  The soil around volcanoes is fertile as it's full of minerals makes it good for growing crops, attracting farmers

  Volcanoes are tourist attractions.

  In Iceland hot water from within Earth crust provides heat and hot water for 90% of buildings. Geothermal Energy generates 25% of countries electricity
• managment strategies


  Monitoring , Prediction, Protection, Planning
• monitoring


  seismometers and lasers to monitor earth movements can be used in early warning systems. scientists can use tell tale signs that come before a natural hazard
• prediction

  predictions aren't reliable but by monitoring the movement of tectonic plates they can forecast which areas will be affected, if it is predicted areas can be evacuated saving lives
• protection


  buildings can be designed to withstand an earthquake by using reinforced concrete or with foundations that absorb the energy, buildings can be strengthened, auto shut off switches to electricity water and gas to prevent fires
• planning


  emergency services trained for the event, educate people so they know what to do, plan evacuation routes, stockpile emergency supplies
• Tropical storms


  Tropical storms develop when the sea temperature. Is 27* or higher and when the wind shear between higher and lower parts of the atmosphere is low. Warm, moist air rises and condensation occurs. This releases huge amounts of energy which makes the storm powerful. The rising air creates an area of low pressure, which increases surface winds. Tropical storms move towards

  the west.
• features of a tropical storm


  Tropical storms are circular in shape , hundreds of km wide and usually last 7-14 days. They spin anti-clockwise in the northern hemisphere and clockwise in the Southern Hemisphere.

  
• Tropical storm Primary effects


  Buildings and bridges are destroyed

  Rivers and coastal areas flooded

  People drown, or are injured / killed by debris
• Tropical storm Secondary effects


  People are left homeless, which can cause distress, poverty, ill health or death due to lack of shelter. There is a shortage of clean water and lack of proper sanitation- this makes it easier for diseases to spread.

  Business are damaged or destroyed causing unemployment.
• Tropical storm Immediate responses


  Evacuate people before the storm arrives

  Rescue people that have been cut off by flooding and treat injured
• Tropical storm Long term responses

  Repair homes or rehouse people that have been displaced

  Repair or replace damaged infrastructure.Repair and improve flood defence systems e.g levees and flood gates
• Typhoon Haiyan


  Typhoon Haiyan struck The Phillipines in south-east Asia in November 2013. category 5 storm one of the strongest recorded with 313km/h winds

  PE - 10,000 deaths, 1.9 million made homeless, 95% of fishing boats destroyed.

  SE -6 million lost there jobs there were no fishing boats which is generally the main source of income in a family,

  TE - Disease outbreak due to lack of water, shelter and medication and schools closed
• Uk weather hazards


  Thunder, Rain, Wind, snow and ice, hail, drought, heatwaves.
• November & December 2010


  A period of heavy snow and cold weather across uk from 25.11.10 - 26.12.10 because of cold air from northern Europe and Siberia caused two long periods of cold with a brief thaw in between.
• Climate change evidence


  Ice and sediment cores - ice sheets are made up of layers of ice - one 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 temperature was each year, Temperature records, Pollen analysis, Tree rings - as a tree grows it forms a new ring each year - the tree rings are thicker in warmer and wet conditions.
• Natural causes of climate change

  Orbital changes, Major volcanic eruptions, solar output