global warming

• What human activity increases greenhouse gas concentrations?

  Certain human activities
• How does burning fossil fuels affect carbon dioxide levels?

  It releases carbon as carbon dioxide
• What has carbon dioxide been locked up for?

  Millions of years
• What is the effect of deforestation on photosynthesis?

  It reduces the amount of photosynthesis
• What happens when less photosynthesis occurs?

  Less carbon dioxide is removed from the atmosphere
• What is happening to landfill sites?

  Their number and size are increasing
• What is the consequence of more waste decomposing in landfills?

  It releases methane
• What do farm animals release during digestion?

  Methane
• What are the main human activities that contribute to greenhouse gas emissions?

  • Burning fossil fuels
  • Deforestation
  • Increasing landfill sites
  • Agriculture (farm animals)