1. A lot of CO₂ is released by cars. 2. The forests are burnt down by farmers. 3. Most of the world's rain is made by forests. 4. Forest fires are photographed by satellites. 5. Millions of animals are killed by deforestation. 6. Three per cent of greenhouse gases are produced by aeroplanes. 7. The sun's heat is trapped by greenhouse gases. 8. Extreme weather is produced by climate change. 9. Carbon dioxide is absorbed by trees. 10. Electricity is produced by power stations.