Air Pollution

The most dangerous city in the world for children due to polluted air…

Mexico City

The Atmosphere contains several gases that make up the majority of Clean Air

• Nitrogen gas (78%) and Oxygen gas (21%)

• Argon

• Carbon Dioxide

• Water Vapor

Polluted Air =• Harmful substances that build up in air

• These substances include: solids, liquids, gases

Air Pollution is due to:

• Human Activities like burning fossil fuels

Some air pollution is considered natural due to its source. Sources include:

• Volcanoes (ash and sulfur dioxide)

• Dust

• Pollen

• Spores

There are two types of pollutants that can affect the environment:

Primary Pollutants:• Put directly into the air by humans: Ex:

INDUSTRY

EXHAUST BURNING

TRANSPORTATION

DEMOLITION

Carbon Monoxide (CO)

• Odorless, colorless, poisonous gas

• Burning…cars, furnace

• Drowsiness and death

Nitrogen Oxide

• Gas with brownish haze

• Vehicle emissions,

power plants, boilers

• Lung cancer, acid rain, respiratory problems

Secondary Pollutants:

• Chemical reactions between primary pollutants, water vapor, and oxygen. Examples:

ACID RAINSMOG

Sulfur Dioxide

1. Gas (smells like rotten eggs)

2. Burning coal, power plants

3. Acid Rain/Harms plants, fish

4. Respiratory problems

5. Corrosive

World Air Quality Problems

• As countries become more developed they are more likely to use fossil fuels.

• Most air pollution comes from vehicles and industry.

• Motor Vehicle Emissions: About 1/3 of all air pollution comes from burning gasoline.

• The Clean Air Act (1970) required: catalytic converters, unleaded gas, improved mpg

Industrial Air Pollution• Industries and power plants: burn fossil fuel for

energy• Huge quantities of sulfur dioxide (coal) and

nitrogen oxide (oil/gas) are released into the air

• Other industries produce Volatile Organic Compound’s (VOC’s)that form toxic fumes

• Dry cleaning, oil refineries, manufacturing, furniture refinisher, auto repair shop, aerosols

SMOG

• In many urban areas, air pollution gets trapped in cities and appears as a gray haze that reduces visibility.

• It is made of sun, air, NO or SO, and ozone

• Worst places for SMOG in US:

• LA

• Denver

• Phoenix

Temperature Inversion

• Diagram:

Temperature Inversion

1. Occur during winter more frequently

2. Little or no wind present3. Pollution can’t escape due to warm

air lid over area4. Cloudy conditions5. Usually requires a weather front to

blow warm air lid out of area