1. Pollution
SNC1D
Fall 2010

4. pH Scale
Logarithmic scale

5. Air movement patterns across U.S.
Main Idea(s) of This Slide –
The lakes in the Eastern United States are more significantly impacted by acid rain primarily due to weather patterns across the U.S. Most air flow across the U.S. moves in a west to east direction. Since acid rain is caused by pollutants in the air, the pollutants will naturally become more concentrated in the east.
Based on: Haines,Transactions of the American Fisheries Society, November 1981

6. Increase in stack height with time
Main Idea(s) of This Slide –
Electrical generators have increased smoke stack heights over the years to ensure that the pollution was injected into higher air flows that will carry the pollution greater distances away from the source. This graph shows the increase in smoke stack height over the years from 1956 to The average smoke stack height reached 600 feet in 1976 and there are stacks that have exceeded 1,200 feet in height.
Based on: Patrick et al., Science Vol. 211, 30 January 1981

7. High smoke stacks inject sulfur and nitrogen emissions into upper atmosphere
Main Idea(s) of This Slide –
Although the tall smoke stacks keep the pollution out of the public view, it has also spread the problem of acid rain.
Photo courtesy of Texas Park and Wildlife Department

8. Combustion of fossil fuels is the main cause of acid precipitation
Rain water: pH 5.6
1980

10. Regions of North America with low soil alkalinity to neutralize acid rain

11. Causes of Acid Rain Air pollution Burning of fossil fuels
- Power plants
- Cars, trucks, airplanes
The main chemicals
Sulfur dioxide
Nitrogen oxides

12. Acid Rain Normal Rain H2O + CO2  H+ + HCO3- A pH of 5.6
Water + carbon dioxide  proton + carbonic acid
Acid Rain
Form of water pollution
More acidic than normal rain
Has pH < 5.6
nitrous dioxide + water  nitrous acid + nitric acid
2NO2 + H2O  HNO2+ HNO3
sulfur dioxide + water  sulfuric acid
SO2 + H2O H2SO4

13. Ecological Effects from Acid Rain in Lake System
Changes begin to occur as soon as a lake starts to lose it natural bases or alkalinity.
A large reduction in the number of plankton & invertebrates.
The rate of decomposition of organic matter decreases
Direct effects on fishes reproductive cycles.
A calcium deficiency in fish leads to bone malformation.
Fish can suffocate as their gills become clogged with aluminum hydroxide.
Songbirds are effected by eating insects contaminated with toxic metals.

14. Before

15. After

17. The Forests are Feeling It
Acid Rain Report
The Forests are Feeling It

19. World’s Biggest Garbage
Dump
One of the Dirtiest
Beaches in the World