Global Warming

• The atmosphere is a layer of gases surrounding the Earth that is held in place by gravity.
• Which three of the following are greenhouse gases (GHGs)?

  Carbon dioxide

  Water vapour

  Methane
• Greenhouse effect 

  1. Solar radiation from the sun passes through the atmosphere and hits the earth.
  2. Some of this energy is reflected straight back towards space, while some is absorbed by the earth and then reemitted towards space.
  3. Some of the reemitted energy makes it all the way to space, but much is absorbed by small molecules called greenhouse gases. 
  4. These molecules then reemit the energy and the whole process of absorption and emission can happen over and over again. 
  5. This trapped energy keeps the atmosphere warmer and more stable than it would otherwise be. 
• True or false? Until now, the earth's atmosphere has always been the same temperature.

  false

  • The earth's temperature has always fluctuated. What is different this time is that it is unnatural and happening very fast.
• What is the difference between global warming and climate change? 

  • Global warming refers to the overall increase in the earth's temperature
  • Climate change is a consequence of global warming and refers to the effects on the climate, such as large-scale shifts in weather patterns
• One effect of global warming is the melting of ice caps. This will increase the volume of water in the ocean and could lead to seasonal flooding, or the submersion of entire islands. This is made worse by the fact that water expands when it is heated, so it will also increase in volume.  
• What is the difference between the climate and the weather?

  • Weather refers to short term atmospheric conditions, like whether it's raining or sunny on a particular day
  • Climate describes the typical weather conditions in an entire region for a very long time
• Which of these is an impact of climate change around the world?

  Species in affected areas may become extinct