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Changing Climate - Coggle Diagram

- - - - Analysis of gases trapped in the layers of ice can tell us what the temperature was when the layer formed
      - Data collected is detailed and reliable and goes back 650,000 years
      - Show that is is normally colder than it is currently
      - Ice sheets are made of layers of ice, one layer is formed each year
    - - By seeing the maximum and minimum extent of sea ice, you can tell how the temperature has changed
      - Data is reliable and accurate, but isn't very old
      - Sea ice declining at a rate of 13.3 percent per decade
      - North West passage used to be very difficult to pass, but now its much easier
    - - Historical diaries show the past climate
      - They can give details about the weather
      - Paintings of fairs on frozen rivers show that winters in Europe were generally much colder 500 years ago than now
      - Not very reliable as they jsut give one person's viewpoint
      - Between 1309-1814, Thames froze atleast 23 times
      - Cave paintings depicted Giraffes in France
    - - Since 1850's global temperatures have been measured using thermometeres
      - Gives a reliable short term record of temperature change
      - Weather stations are evenly distributed
      - Nasa suggested that the temperature has increased by 0.6 degrees since 1950
      - Average temperaure increased by 1.15 since records began
    - - 60 million year old crocodile fossils found in North Dakota suggest it was much warmer than it is now
      - Snows in Kilamanjaro have melted by 80% since 1912
      - Wooly Mammoth like Mastodons were found in Florida, showing it use to be much cooler
- - - - Path of the earth's orbit changes from an almost perfect circle to an ellipse
      - Changes every 100,000 years
    - - The angle earth is tilted at as it orbits
      - Changes every 41,000 years
    - - Axis of the earth wobbles as it spins
      - Cycles every 26000 years
    - - These cycles affect how far the earth is from the sun, and the angle at which the sun's rays hit the earth
      - This changes the amount of solar radiaiton the earth receives, and this its temperature
      - Tilt and wobble affect how much solar radiaiton is received at different latitudes at different times of the year
      - Orbital changes could cause glacial and itnerglacial periods
  - - - Farming
        
        Cattle produces lots of methane
        
        Rice paddies also emit methane
        
        1.6-2.7 billion tonnes of greenhouse gases annually
      - Burning fossil fuels
        
        CO2 is released into the atmostphere when fossil fuels are burnt
        
        Coal, oil, natural gas and petrol
        
        75% of mankind's emisisons
      - Deforestation
        
        Plants remove CO2 from the atmostphere and convert it into organic matter through photosynthesis
        
        Cutting down trees mean they no long take in CO2
        
        Trees are lagre carbon sinks
        
        CO2 is rleeased when trees are burnt
      - Landfill
        
        55% of global waste is buried. which emits methane as it decomposes
        
        30-70 million tonnes annually