Air pollution

1. Air pollution http://www.bbc.co.uk/schools/gcsebitesize/science/21c_pre_2011/atmosphere/chemicalsairact.shtml

2. Air pollution • Early times when there were fewer people natural resources would repair the damage. • Winds and rain remove pollutants • Streams and decomposers purify water • Main factor was time • I. Humans are affecting ecosystems in 3 ways • A. We are interrupting natural cycles ex. Fertilizers, pesticides, and herbicides • B. The flow of energy through the ecosystems have been disrupted- waste, CO2, and air pollution

3. Air pollution • C. Diversity of ecosystems can be reduced- single crop farming • II air quality • A. Volcano’s dump piousness gases that can greatly effect the atmosphere. Ex Pompeii

4. B. Industrial revolution- air composition is greatly affected by wide scale combustion of fossil fuels • C. Air pollutant- any substance in the air that is concentrated enough to harm living things or damage human made objects- smoke CO, SO2

5. Air pollution • III. Big five pollutants • A. Most of the pollution occurs in the troposphere the lowest layer of the atmosphere. • B. Some are carried by currents into the stratosphere • C. Carbon Monoxide- 90% of the carbon monoxide in the troposphere is naturally occurring • 1. Formed when carbon is not completely burned. • 2. bigger problem for higher altitude means more carbon monoxide forming instead of CO2

6. Air pollution • 3. High level pose health threat to humans. It bonds to the hemoglobin in red blood cells instead of oxygen • 4. causes oxygen deprivation and eventually suffocation. • 5. Have reduced the levels in cities with by improving emission control systems on cars and increasing oxygen content in fuels. • 6. Internal sources are furnaces, fireplaces, and kerosene heaters that are improperly installed

7. Air Pollution • D. Unburned hydrocarbons or volatile organic compounds. • 1. Come from incomplete combustion of gasoline and evaporation of petroleum fuels, industrial solvents, and paints • 2. These can react to form photochemical smog • 3. VOC’s react to form Ozone, O3, which is highly reactive and is a pollutant in the troposphere. • 4. solution: catalytic converters break apart hydrocarbons and reduced emissions of hydrocarbons from fuels • E. Nitrogen oxides- 78% of the atmosphere is nitrogen

8. Air pollution • 1. Nitrogen reacts at high temperatures like those found in furnaces to create NO • 2. These bond with additional oxygen and sunlight to form brownish photochemical smog • 3. Catalytic converters are now designed to reduce nitrogen oxide emissions

9. Air pollution • E. Sulfur oxides • 1. The largest natural contributor is volcano’s • 2. Man made gases are produced by electric power plants burn coal, oil, or gas to produce electricity and cars • 3. These form sulfuric acid in smog that is corrosive and can cause lung damage. • 4. Have reduced these emissions by removing sulfur from fossil fuels • 5. They can be removed from smoke stack emissions by adding limestone- called scrubbing

10. Air Pollution • F. Particulates- small solid or liquid particles suspended in the air. Most are natural but some come from automotive emissions and industrial combustion emissions. • 1. They stain buildings and other materials, reduce visibility, and contribute to climate changes • 2. These have been reduced by pollution control equipment on industrial and power plants and stricter regulation of the burning of solids • IV. Monitoring air quality • A. Air quality index- EPA tells how polluted local air is and associated health effects

11. Air Pollution • B. More pollution the more the health concerns. • Cities are cleaner than 25 years ago but still have a long way to go. • V.. Indoor air pollution • A. Includes building materials, where the building is, furnishings, and heating and cooling. • B. Bacteria and mold • 1. bacterial mold and mites breed in air conditioning units, ducts, and humidifiers • 2. can be spread throughout building through air duct system

12. Air Pollution

13. Air Pollution • 3. making sure that the ground slopes away from the building reduces molds and bacteria • 4. adequate ventilation and use mold cleaning products in the bathrooms. Keep humidity levels below 60% • C. Tobacco smoke- causes lung cancer, and heart disease. Is now banned from buildings • D. Carbon Monoxide- from furnaces, car exhaust, fireplaces, and cigarette smoke. CO detectors help to monitor levels • Have your furnace checked regularly

14. Air Pollution • E. CO2 Build up with poor circulation. • F. Radon gas- comes from the soil and builds up in lower level or dissolves in water and comes in cracks • Get your home inspected • G. VOC volatile organic compounds found in house hold products and can cause cancer • Close the lid • H. Noise-

15. Air pollution and climate change • VI. Greenhouse effect • A. Climate-the average weather- this has changed dramatically on earth over time • B. Since the ice age the earth has been warming up. The question is whether or not we are influencing it • C. Greenhouse effect- gases in the atmosphere trap the suns rays as they try to exit. This traps the heat in the atmosphere • 1. CO2 is one of these gases that is formed by the burning of fossil fuels

16. Greenhouse effect • 2. Plants help to reduce the amount of CO2 by taking it in during photosynthesis. Unfortunately we are losing many natural areas that contain plants and trees • 3. The Climate question

17. Greenhouse effect • 4. Greenhouse gases include • CO2, CFC’s- refrigerants and Styrofoam, Methane, and water vapor • VII. Depletion of the ozone layer • A. This layer has been thinning out in the atmosphere • B. First line of defense against ultraviolet rays • C. 1960- CFC’s chlorofluorocarbons became popular for refrigeration and aerosol cans. Can break down into chlorine atoms that destroy ozone