Learning Goal: Explain the sources of air pollution and causes of acid rain, the affect it has on ecosystems and humans, and how it can be reduced. Agenda: Discuss aspects of air pollution & acid rain Conduct an experiment to determine which source was the greatest contributor to acid rain and what can be used to neutralize it Homework: Complete the analysis questions from the activity

What is Air Pollution? Any substance released into the atmosphere that causes damage to the environment, human health, and/or quality of life.

Sources of Air Pollution 1.Stationary and Area Sources –power plants, chemical and manufacturing industries. 2.Mobile Sources –vehicles, recreational vehicles, boats, planes, and trains. 3.Agricultural Sources –fertilizers, herbicides, pesticides, and animals produce manure that emits gases. 4.Natural Sources –erupting volcanoes, fires, sea spray, dust storms, pollen

What is Acid Rain? Precipitation with a pH lower than 5.6 Affects ecosystems Damages buildings Ruins monuments Affects health Costs money

Where does it come from? Coal burning power plants (electric utilities) Automobile emissions (NOx, CO, VOCs)

How it works Sulfur dioxide and nitrogen oxides released into the air combine with water and become sulfuric acid and nitric acid. These acids fall to earth as rain, snow, sleet, or hail.

How it affects ecosystems Affects Buffering Capacity - the ability of lakes and soils to neutralize the acidity or alkalinity of it’s environment is reduced Soil: It brings out soil toxins which end up in the water and absorbed through the roots of trees. High-elevation forests soak in acidic clouds, which strip leaves of nutrients and break down trees' ability to resist cold. Bodies of Water: It increases nitrogen in the water, which increases algae growth. Bacteria then decompose the dead algae and soak up the water's available oxygen (dissolved oxygen). Fish, shellfish, sea grass beds and coral reefs die in the algae- choked, oxygen-depleted waters. Scientists estimate that 10 percent to 45 percent of human- produced nitrogen that winds up in coastal waters comes from atmospheric deposition [Source: Environmental Protection Agency].Environmental Protection Agency

Trees killed by acid rain in the Smoky Mountains.

How it affects buildings and monuments Erodes building materials like marble and limestone more rapidly than normal Causes metals to rust rapidly

How it affects health Biodiversity is reduced –alters populations in oceans, lakes, rivers, streams and ponds. Human health –The sulfate and nitrate particulates of dry deposition can cause asthma, bronchitis and heart problems. –The NO x also reacts with other chemicals in the air to form ground-level ozone, which aggravates and weakens the respiratory system. (source:

What can be done? Power plants use: –Low sulfur coal –Wet scrubbers (trona) –Electrostatic precipitators –Flue gas desulphurization systems –low NO x burners Vehicles use: –Catalytic converters help remove NO x Use alternative forms of energy –Wind, nuclear, solar and hydropower don’t release SO x, NO x Liming the waters to buffer the acidity Reduce energy use and automobile use Liming process