Climate Change Review

• Atmosphere thin layer of gas that surrounds the earth

  • protects us from harmful radiation and contains oxygen
• layers of atomosphere

  1. troposphere
  2. stratosphere
  3. mesosphere
  4. thermosphere
• Troposphere 12 km

  • almost all weather and clouds appear here
  • air pressure drops as altitude increases
  • 75% of the air is here
• Stratosphere 12 km-50 km

  • ozone layer is here ( absorbs UV light )
  • warmer than troposphere because of UV energy
• Mesosphere 50 km-85 km

  • meteors burn here
  • air pressure drops when altitude increases
• Thermosphere 500 km-1000 km

  • extremely thin air
  • Leo (low earth orbit) satellites orbit here
• Exosphere

  • where atmosphere merges into space vaccum
• Compositon of atomosphere

  • nitrogen 78%
  • oxygen 21%
  • variable gasses - water vapour
• Greenhouse gasses

  • water vapour H2O
  • methane CH4
  • carbon dioxide CO2
• Greenhouse effect the process that keeps the earths surface warm
• energy from the sun comes down as visible light the earths atmosphere is largely transparent and the earths surface absorbs it then re-radiates back into space and infrared light
• earths energy balance budget between the amount of energy coming from the sun to earth and energy outgoing from earth to space
• solar energy is measured in w/m2
• visible light is reflected by white surfaces like clouds and ice
• visible light is absorbed by warm grounds and oceans
• Processes that add carbon into atmosphere

  • cellular respiration (breathing)
  • Anaerobic decomposition (decaying)
  • Volcanic eruption (volcanoes)
  • Burning fossil fuels (factories)
• Process that remove carbon

  • photosynthesis
  • ocean dissolving CO2
• combustion reactions will always be fuel+oxygen=carbon dioxide+water
• what is the most abundant greenhouse gas?

  water vapour