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What is air pollution?
Air pollution is when unwanted chemicals, gasses, and particles enter the air and the atmosphere causing harm to animals and damaging the natural cycles of the Earth.
Natural Causes of Air Pollution
Some sources of air pollution come from nature. These include eruptions of volcanoes, dust storms, and forest fires.
Human Causes of Air Pollution
Human activity is a major cause of air pollution, especially in large cities. Human air pollution is caused by things such as factories, power plants, cars, airplanes, chemicals, fumes from spray cans, and methane gas from landfills.
Burning Fossil Fuels
One of the ways that humans cause the most air pollution is by burning fossil fuels. Fossil fuels include coal, oil, and natural gas. When we burn fossil fuels this releases all sorts of gasses into the air causing air pollution such as smog.
Effects on the Environment
Air pollution and the release of gasses into the atmosphere can have many negative effects on the environment.
- Global warming - One type of air pollution is the addition of carbon dioxide gas into the air. Some scientists believe that releasing too much carbon dioxide into the atmosphere is one of the causes of global warming. This upsets the balance of the carbon cycle.
- The ozone layer - The ozone layer helps protect us from harmful rays from the sun. It is getting damaged from air pollution such as methane gas from livestock and CFCs from spray cans.
- Acid Rain - Acid rain is created when gasses such as sulfur dioxide get high into the atmosphere. The wind can blow these gasses for miles and then they get washed out of the air when it rains. This rain is called acid rain and can damage forests and kill fish.
Smog in the city makes it hard to breathe and see
Effects on Health
Air pollution can also make people sick. It can make it difficult to breath and cause diseases such as lung cancer, respiratory infections, and heart disease. According to the World Health Organization, 2.4 million people die each year from air pollution. Air pollution can be especially dangerous to children living in big cities with bad smog.
Air Quality Index
The Air Quality Index is a way for the government to alert people to the quality of the air and how bad the air pollution is in an area or city. They use colors to help you determine if you should go outside.
- Green - the air is good.
- Yellow - the air is moderate
- Orange - the air is unhealthy for sensitive people like the elderly, children, and those with lung diseases.
- Red - Unhealthy
- Purple - Very unhealthy
- Maroon - Hazardous
The actual gas or substance that causes air pollution is called a pollutant. Here are some of the major pollutants:
- Sulfur dioxide - One of the more dangerous pollutants, sulfur dioxide (SO2) can be generated by burning coal or oil. It can cause acid rain as well as respiratory illnesses like asthma.
- Carbon dioxide - Humans and animals breathe out carbon dioxide (CO2). It is also released when fossil fuels are burned. Carbon dioxide is a greenhouse gas.
- Carbon monoxide - This gas is very dangerous. It is odorless and is produced by cars. You can die if you breathe too much of this gas. This is one reason why you should never leave your car running in the garage.
- Chlorofluorocarbons - These chemicals are also called CFCs. They were used in many devices from refrigerators to spray cans. They are not used as much today, but caused significant damage to ozone layer during the time they were heavily used.
- Particulate matter - These are tiny particles like dust that get into the atmosphere and make the air we breathe dirty. They are linked to diseases like lung cancer.
Anytime you can use less energy, like electricity or gasoline, it can help reduce air pollution. You can help by turning off the lights when leaving your room and not leaving the TV or computer on when you're not using it. Driving less helps a lot too. Be sure to talk to your parents about carpooling with friends and planning errands so that you can get them all done in a single trip. This saves money on gas as well, which everyone likes!
Facts About Air Pollution
- A thick smog formed in London during the late 1800s. It was called the London Fog or the Pea Soup Fog.
- The biggest single air polluter is road transport such as cars.
- Air pollution in the United States has improved since the introduction of the Clean Air Act.
- The city with the worst air pollution in the United States is Los Angeles.
- Air pollution can cause your eyes to burn and make it difficult to breathe.
- Indoor air pollution can be much worse than the pollution outdoors.
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