Environment Key Issue #2: Why are resources being polluted?
Air Pollution Definition: a concentration of trace substances at a greater level than occurs in average air Most common – carbon monoxide, sulfur dioxide, nitrogen oxides, hydrocarbons, and solid particulates Three human activities that cause pollution: motor vehicles, industry, and power plants Pollution results from the burning of fossil fuels Three scales of pollution: global, regional, and local
Global Warming Burning fossil fuels may be causing the earth’s temperature to rise Carbon dioxide in the atmosphere has risen more than ¼ in the past 200 years The average temperature of Earth’s surface has increased 2°F during the past 100 years Greenhouse effect
Global-Scale Ozone Damage The ozone layer (gases) absorbs UV rays from the sun The ozone layer is threatened by pollutants called chlorofluorocarbons (CFCs) PEDs were required to stop using CFCs by 2000, and PINGs are supposed to stop by 2010
Regional-Scale Acid Deposition Especially in densely populated areas such as western Europe and eastern North America Acid precipitation
Local-Scale Urban Air Pollution 1. Carbon Monoxide – proper burning in power plants produces carbon dioxide, but improper combustion produces carbon monoxide 2. Hydrocarbons – result from improper fuel combustion as well as evaporation of paint solvents Photochemical smog – formed by hydrocarbons and nitrogen oxides in the presence of sunlight; cause respiratory problems, stinging of the eyes, and an ugly haze over the city 3. Particulates – dust and smoke particles
Photochemical Smog in Mexico City
Water Pollution
Point vs. Nonpoint Point Nonpoint
Impact on Aquatic Life
Wastewater and disease Drinking this: Results with this:
Land Pollution