changing climate

• causes of climate change: hotspots

  1. sunspots are cooler areas of the sun's surface that are visible as dark patches. they increase the sun's output energy
  2. a cycle comes and goes every 11 years
  3. fewer hotspots=cooler climate
• cause of climate change: milankovich cycles

  stretch: earths orbit changes from a circle to an elipse and back every 96000 years

  tilt: the tilt (axis) changes over a cycle of 41000 years

  wobble: the axis of the earth wobbles like a spinning top on a cycle of about 22000 years

  • these cycles affect how far the earth is from the sun and the angle the sun's rays hit the earth
• causes of climate change: volcanic activity

  1. Major volcanic eruptions eject large quantities of material into the atmosphere
  2. some of these particles reflect the sun's rays back out to space, so the earth's surface cools
• enhanced greenhouse effect

  additional heat retained due to the increased amounts of carbon dioxide and other greenhouse gases that humans have released into the earth's atmosphere 
• human activities contributing to the greenhouse effect

  • farming - livestock produce methane
  • burning fossil fuels - releases carbon dioxide into the atmosphere
  • cement production - cement is made from limestone which contains carbon
  • deforestation - less plants to remove carbon dioxide
• global effects on climate change

  social:

  • increased threat of wildfires
  • not enough water
  • low crop yield can lead to famine

  economic:

  • more money spent on predicting extreme weather
  • farming - some crops have suffered

  environmental:

  • temps rising causing glaciers to shrink and ice sheets to melt - increasing sea levels
  • loss of polar habitats, coral reefs bleaching
• effects of climate change on the UK

  social:

  • deaths from cold-related illnesses will decrease
  • drier summers will affect water availability

  economic:

  • boost in tourism due to warmer weather
  • change in fish populations
  • increased productivity of some crops

  environmental:

  • temps increasing
  • more frequent droughts
  • sea levels will increase
• evidence of climate change

  1. ice cores - ice sheets are made up of layers of ice (one layer is formed each year), drill ice sheets to get cores
  2. sea ice positions - forms near the poles
  3. diaries and paintings
  4. temperature data