natural causes of climate change

• orbital changes are variations in the way the earth moves around the sun
• stretch (eccentricity) 


  the path of the earths orbit around the sun

  • changes from a perfect circle to an oval
• tilt


  the earths axis is tilted as it orbits the sun
• wobble (precession)


  the axis wobbles like a spinning top
• these cycles affect the amount of solar radiation the earth receives

  if it receives more energy it gets warmer
• volcanic activity is another cause of climate change
• major volcanic eruptions eject large quantities of material e.g. ash into the atmosphere
• volcanic activity 


  some of these ash particles reflects the suns rays back out to space therefore cools the earths surface
• solar output is another cause of natural climate change
• periods when solar output is reduced may cause earths climate to cool
• asteroid collisions is another cause of natural climate change
• asteroid collisions 


  can throw up huge amounts of dustinto the atmosphere
• asteroid collisions 


  these particles prevent the suns energy from reaching earth so global temperatures fall