Environmental Science Name: Air Section Goal

1. 
   smog
   
2. 
   temperature inversion
   

Motor Vehicle Emissions

• 
  Over _________ of our air pollution comes from gasoline burned in motor vehicles
  
• 
  Approximately _________ of air pollution comes from by cars and trucks, the rest by commercial vehicles; In 1995, US vehicles traveled over 2 _______________ miles, by 1998, Americans drove over 2.6 trillion, ______________ driven by passenger cars, the rest by trucks and buses
  

Controlling Vehicle Emissions

• 
  Clean Air Act (1970, strengthened in 1990) gave the __________ the authority to regulate automobile emissions
  
• 
  EPA required gradual elimination of ______ in gas, resulting in more than a 90% drop of lead pollution;
  
• 
  Catalytic converters (required in automobiles) ______________ exhaust gases of pollutants before they are able to ____________ the tailpipe; EPA estimates that vehicles burn fuel __________ more efficiently, with ____________ fewer emissions of pollutants (except CO₂) than 30 years ago
  
• 
  Driving less is an effective way of _______________________ air pollution (ex: carpooling with one other person would reduce ___________ million lbs. of CO₂ into the air
  
• 
  Car manufacturers are making cars to run on fuels which cause __________ air pollution (solar, batteries, hydrogen, natural gas)
  
• 
  Brazil has over _______million cars that run on ethanol (made from remnants of sugarcane plants)
  
• 
  Ethanol is less polluting; _______________ to form less CO2 and H2O
  

California Zero-Emissions Vehicle Program

• 
  Zero-emission vehicles have _______ tailpipe emissions, ________ emissions from gasoline and ___________ emission-control systems that deteriorate over time.
  
• 
  By 2016, California requires ___________ of all vehicles sold to be zero-emission vehicles (SUVs, trucks, sm. vans and autos); at present, ZEVs (electric vehicles) and advanced battery vehicles are being demonstrated by __________________automobile companies; vehicles powered by hydrogen are being developed; some partial zero-emission vehicles are included (hybrid-electric, methanol fuel cells).
  
• 
  Zero-emission programs have also been adopted in Maine, Massachusetts, New York and Vermont.
  

Smog

• 
  When air pollution_____________ over urban areas and reduces visibility, it is called SMOG (smoke and fog); chemical reaction involving sunlight, nitrogen oxides and hydrocarbons.
  
• 
  Pollutants released by automobiles and industries are the ________________ causes of smog
  
• 
  Cities, like Los Angeles, Denver and Mexico City, suffer the most from ____________ (dry, sunny locations with dense traffic)
  

Temperature Inversions

• 
  Air circulation usually keeps _____________ pollution from reaching dangerous levels (sun heats the surface of the Earth and air near it, warm air rises through the cooler air, carrying pollutants away from ____________________ surface)
  
• 
  Sometimes pollution gets ___________________ near Earth’s surface (temperature inversion- air above is warmer than the air below it); traps the pollutants below with the cooler air. If a city is located in a valley (Los Angeles), the city has a ________________ chance of experiencing temperature inversions
  

Use the Internet to find as many respiratory diseases, such as asthma, that can be aggravated by air pollution. Record your findings into the table provided. Be sure to list the disease, its symptoms, how it is treated, the age group most commonly afflicted and the relationship between the disease and air pollutants.

1. 
   Describe the way in which smog forms.
   

2. 
   Define the term temperature inversion. Explain how temperature inversion traps pollutants near Earth’s surface.