HKDSE Geography/M7/Human Factors in Global Warming
< HKDSE Geography | M7
Numerous human factors lead to global warming.
Carbon dioxide
[edit | edit source]The main greenhouse gas, carbon dioxide is generated in the following situations:
- Burning of fossil fuels: The burning of coal, oil and natural gas
- Burning of petroleum-based fuels by transport: The combustion of fuel for transport, such as aeroplanes and land vehicles
- Forest fires: Forests are important carbon sinks and carbon dioxide is released into the atmosphere by forest fires.
- Incinerators: Carbon dioxide is produced when burning solid waste in incinerators.
Methane
[edit | edit source]- Livestock rearing: Rearing of livestock, particularly cattle ranching, produces methane.
- Wet rice cultivation
- Decomposition of solid waste in landfills
- Fossil fuel and biofuel combustion also causes methane release
Nitrous oxide
[edit | edit source]- Use of nitrate fertilisers in arable farming: When nitrate fertilisers are decomposed in soil, nitrous oxide is released.
- Fossil fuel combustion
- Combustion of solid waste in incinerators
- Nylon production
Chlorofluorocarbons (CFCs)
[edit | edit source]- Air conditioning and refrigeration
- Aerosol sprays
- Cleaning solvents
- Styrofoam
