Unit 3: Chapter 12 notes AIR
12.1: What Causes Air Pollution? Name 5 primary air pollutants, and give sources for each. Name the 2 major sources of air pollution in urban areas. Describe the way in which smog forms. Explain the way in which a thermal inversion traps air pollution
Primary vs. Secondary Pollution Primary pollutants: pollutants that are put directly into the air by human activity. ex. Soot, CO, NO, SO2 Secondary pollutants: form from primary pollutants reacting with other primary pollutants or with naturally occurring substances in the atmosphere. ex. ground-level ozone (last week’s blog question)
Sources of Primary Pollutants Emissions from vehicles (~1/3) Industrial processes Construction Agriculture Fires Forestry Burning fossil fuels Power plants (~2/3 of SO2 and ~1/3 of NO) Household products/cleaners (VOC…vaporize readily and form toxic fumes)
Particulate Matter Can be collected and measured 2 “categories” Fine (from vehicle emissions/burning fuel) Coarse (from fields, roads, wood-burning fireplaces)
Smog Formation…Urban Areas! Results from chemical reactions that involve sunlight, air, automobile exhaust, and ozone. Primarily from vehicles and industries Temperature Inversions When the air “above” is warmer than the air “below” This causes pollutants to be “trapped” below with the cooler air
EPA Regulations Clean Air Act (1970 & 1990) EPA has the authority to regulate vehicle emissions in the US 90% decreases in lead pollution (lead removed from gasoline = “unleaded”) Catalytic converters = 35% increase in fuel efficiency with 95% fewer emissions of pollutants (excluding CO2) Require scrubbers (a machine that moves gases through a spray of water that dissolves many pollutants) or electrostatic precipitators
12.2: Air, Noise, and Light Pollution Describe 3 short-term effects and 3 long-term effects of air pollution on human health Explain what causes indoor air pollution and how it can be prevented Describe 3 human health problems caused by noise pollution Describe solutions to energy waste caused by light pollution
ON YOUR OWN!!!
12.3: Acid Precipitation Explain the causes of acid precipitation Explain how acid precipitation affects plants, soils, and aquatic ecosystems Describe ways that countries are working together to solve the problem of acid precipitation
Acid Rain… What-Where-When-Why-How-“Who”? What?: any form of precipitation that has a high concentration of acids (pH < 5; normal precipitation has a pH of ~5.6…acidic due to CO2 in the atmosphere). Where?: all over the globe! An international problem. ~1/2 of all the acid rain that falls in SE Canada results from pollution produced in the NE U.S. Canda-U.S. Air Quality Agreement in 1991 When? & Why?: caused from burning fossil fuelsrelease oxides of sulfur and nitrogen; when these oxides combine with water in the atmosphere, they form sulfuric and nitric acid.
How? & “Who”?: Affects soilplants (roots damaged, toxic metals absorbed, clogs openings on the surface of plants) Affects aquatic ecosystems due to the decreased pH of the water (called acidification) fish kills; reproduction of fish and amphibians (produce fewer eggs, birth defects, and offspring are unable to reproduce) Worst is spring (accumulated acidic snow meltrushes into lakes; called acid shock).