Pollution SNC1D Fall 2010

pH Scale Logarithmic scale

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

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 1976. 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

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

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

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

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

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

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.

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The Forests are Feeling It Acid Rain Report The Forests are Feeling It http://archives.cbc.ca/environment/pollution/dossier/584/

World’s Biggest Garbage Dump http://www.youtube.com/watch?v=XxNqzAHGXvs&list=QL&feature=BF One of the Dirtiest Beaches in the World http://www.youtube.com/watch?v=9eefyztmaII&feature=channel