Energy & Its Impact on Global Society Jerome K. Williams, Ph.D. Saint Leo University Dept. Mathematics & Sciences

Chapter 8: Air Pollution & Energy Use Properties & Motion of Atmosphere Air Pollutants & Sources – Acid Rain – Photochemical Smog Environmental Issues: Air-Quality Standards

Properties & Motion of Atmosphere Air is a mixture of gases (Table 8.1) Majority of air is nitrogen (78%) and oxygen (21%)

Properties & Motion of Atmosphere Air pollutants are substances added by humans that are toxic or irritants to animals, vegetation, or property

Properties & Motion of Atmosphere Examples of Air pollutants carbon monoxide (CO)carbon dioxide (CO 2 ) sulfur dioxide (SO 2 )sulfur trioxide (SO 3 ) heavy metals (lead, mercury, cadmium) iron carbon soot (ash)

Properties & Motion of Atmosphere Vertical motion of air and winds are important mechanisms for dispersing air pollutants Temperature inversion occurs when warm air layer lies on top of cooler part; thus stopping atmospheric dispersion (mixing) of air pollutants

Air Pollutants & Their Sources Air Pollutants: Three Varieties – Gases – Particulates (small particles of solids) – Aerosols (small droplets liquid suspended in gas) – 135 million tons emitted into air over USA (this amounts to 1.3 kg/day/person)

Air Pollutants & Their Sources Air Pollutants: Sources – Stationary(Power Plants, Industries) – Moving Sources (Vehicles) – Natural Sources (Volcanoes, Biological Decay, Forest Fires, Ocean Spray) – Pollutant levels measured in parts per million (ppM) unit

Air Pollutants & Their Sources Carbon monoxide (CO) – Odorless, colorless, poisonous gas – Produced primarily in vehicle engines by the incomplete combustion of carbon found in gasoline fuel – Binds to hemoglobin in blood; prevents oxygen from reaching cells in body

Air Pollutants & Their Sources Sulfur oxides (SO 2 & SO 3 ) – Colorless gas; suffocating odor; powerful irritant – Comes from burning of coal (6% sulfur by weight) – Sulfur reacts with oxygen to form SO 2 and continues to form SO 3 – Oxides combine with water vapor to produce acid rain which falls back to Earth

Air Pollutants & Their Sources

Acid Rain Video do do

Air Pollutants & Their Sources Nitrogen oxides (NO, NO 2 ) – Origin: fossil fuel burning in vehicles and power plants – Photochemical Smog (observe brown haze due to NO 2 ) – Also plays a role in acid rain phenomenon – Ozone plays a role in process

Photochemical Smog Video yQ2CSU yQ2CSU

Air Pollutants & Their Sources Indoor Air Pollution – Indoor air pollution concentrations can be many times greater than outside levels – 80% of time spent indoors (home & work or school) – Table 8.4

Environmental Issues: Air-Quality Standards Clean Air Act(1970) – NAAQS (National Ambient Air Quality Standards) was established to reduce levels of six pollutants linked to human health effects – Sulfur oxides, nitrogen oxides, particulates, ozone, carbon monoxide and lead

Environmental Issues: Air-Quality Standards Mini-Paper: Clean Air Act (Pollutant Levels) – Each student assigned one air pollutant – Determine air pollutant concentration that is acceptable today in US; compare to level in 1970s – How does one reduce the aforementioned pollutant while preserving a favorable benefit to cost ratio? – Essay is 600 – 800 words; due November 10

Problems 10, 20, 23