Climate Change Causes

HideShow resource information
View mindmap
  • Climate Change Causes
    • Earth's Orbit
      • Variations affect the receiving of the Sun's energy
      • 3 factors of orbit affect climate
        • 1. Stretch
          • Change of Earth's path from circle, to ellipse and back
            • Timescale of 96,000 years
              • Distance from Sun varies at different times of year
                • Closest in January, furthest in June
        • 2. Tilt
          • Change of Earth's angle on it's axis
            • Timescale of about 41,000 years
              • Angle varies from 21.5 - 24.5 degrees
        • 3. Wobble
          • Earths axis also circles on a 22,000 year cycle
            • Will gradually cause summer to be in Jan, winter in June
    • Solar Output
      • Not constant
      • Sunspots are dark areas increasing energy output of Sun
        • Increase and Decrease in an 11 year cycle
      • Little ice age in 17th Cent coincided with low sunspot activity
    • Cosmic Activity
      • Meteors and asteroids make large craters, throwing up material
        • Material can block out the sun's energy
          • Up to years, changing climate
    • Volcanic Activity
      • Large scale eruptions emit lots of material
        • Block out sunlight, changing climate
    • Human Activities
      • Recent global warming thought to be due to human
      • Enhanced GHG emissions
        • EG. Methane, CO2, water vapour
        • GHGs absorb outgoing energy, stopping it from leaving
          • Keeps the planet warm
            • Without GH effect, planet would be 30'c cooler
        • CO2 levels have increased from 280ppm to 380ppm since industrial revolution
          • Burning of fossil fuels, trees etc
        • Increased GHGs in the atmosphere
          • Too much absorption due to too much GHGs
            • Planet warms up
      • CO2 Sinks destruction
        • Sinks store CO2, keeping it out of the atmosphere
        • Oceans are biggest sinks, CO2 dissolves in sea water
          • Plants also big sinks. CO2 converted during photosynthesis
        • Thought that sinks won't cope with increasing GHGs
          • More straight into atmosphere


No comments have yet been made

Similar Geography resources:

See all Geography resources »See all Natural hazards resources »