Presentation on theme: "15 -4 The Air We Breathe pgs. 408-413 IN: What are the different ways that humans impact the atmosphere?"— Presentation transcript:
15 -4 The Air We Breathe pgs. 408-413 IN: What are the different ways that humans impact the atmosphere?
Terms & Objectives Terms: Primary pollutants secondary pollutants acid precipitation Objectives: Describe the major types of air pollution. Name the major causes of air pollution. Explain how air pollution can affect human health. Explain how air pollution can be reduced.
Air Quality is determined by the amount and type of pollutants in the air. –Natural sources produce a greater amount of pollutants than humans do.
Human activities cause most of the air pollution in cities. This pollution may be solid, liquid, or gas.
Types of Pollutants Primary pollutants are put directly into the air by human or natural acitivity –Ex. (volcanic eruptions and vehicle exhaust)
Types of Pollutants Secondary pollutants form when primary pollutants react with other pollutants, water vapor, sunlight, or some other substance. –Ex. (ground level ozone and smog are both photochemical reactions related to car exhaust.)
Sources of Human-Caused Air Pollution Most air pollution comes from transportation. –Car exhaust contribute about 60% in the U.S.
Industrial air pollution comes from burning fossil fuels which releases oxides (like sulfur oxides) into the atmosphere. –Some industries also release poisonous fumes into the air
Chemicals in household cleaners, new carpets, paints, cooking smoke, and other sources, may pollute indoor air. Some air inside buildings may be worse than the air outside.
Air pollution is a local and global concern. –Winds move pollutants from one place to another.
Acid precipitation is caused by oxides of sulfur and nitrogen reacting with water droplets in the atmosphere to form sulfuric acid and nitric acid.
Some chemicals such as Chlorofluorocarbons react with the ozone in the ozone layer to break it down into oxygen which allows the sun’s harmful ultraviolet rays to reach the Earth’s surface. Ultraviolet rays are the leading cause of skin cancer.
Effects on Human Health Daily exposure can lead to asthma and other serious health problems. Children and elderly people and people with allergies or lung problems are especially vulnerable.
Cleaning up our act The Environmental Protection Agency (EPA) has passed the Clean Air Act 1970 giving the authority to control the authority to control the amount of air pollutants by any source. –Car smog checks –Requires use of scrubbers to remove the harmful pollutants such as from burning coal.
How does dirt get in your house? Windows Doors Air Conditioning Pets You!
Facts About Breathing You breath about 26,000 times a day (16- 18 breaths per minute) That is about 150 full bathtubs of air We breath in over a billion small particles a day (1,000,000,000) The average house collects about 2 pounds of dust a week