Air Pollution
Biology: Edexcel IGCSE, topic 5.2.3
Air Pollution
Air pollution comes from many different sources.
Burning fossil fuels
- Burning fossil fuels releases large amounts of greenhouse gases into the atmosphere that would otherwise have been locked away for millennia.
- Methane and carbon dioxide enhance the greenhouse effect, causing global warming and climate change.
Agriculture
- Many farming practices, such as rice paddies and cattle farms release huge amounts of methane into the atmosphere.
- Industrial processes linked to agriculture (such as producing fertiliser) emit nitrous oxides, which contribute to acid rain.
Power stations and cars
- Power stations and cars constantly pump gases into the atmosphere.
- Sulfur dioxide dissolves in atmospheric moisture to form acid rain, which has been shown to negatively impact forest, freshwater and soil ecosystems as well as human health.
- Most car exhausts pump out significant amounts of carbon monoxide, which is toxic to humans and other animals because it binds to haemoglobin, reducing the oxygen-carrying capacity of blood.
Cooling systems
- CFCs are a group of gases released from aerosol cans, refrigerators and air conditioners.
- CFCs have been linked to creating a hole in the 'ozone layer'- a layer in the Earth's atmosphere that protects us from harmful radiation.
Test yourself on Air Pollution
What is formed when sulfur dioxide dissolves in atmospheric moisture?