Chapter 20 Air Pollution

Atmosphere as a Resource Atmospheric Composition __: 78.08% __: 20.95% __: 0.93% __: 0.04% Ecosystem services Blocks _________ Moderates _________ Redistributes water

Air Pollution - Terminology Chemicals added to the atmosphere by natural events or human activities in high enough concentrations to be harmful Primary Air Pollutant __________________________________________________________________________________ Secondary Air Pollutant Harmful substance formed in the atmosphere ___________________________________________________________________________________________________________________________

Major Air Pollutants

Particulate Material Thousands of solid or liquid particles suspended in air Ex: _______________________________________________________________________ Dangerous ____________________________________

Nitrogen and Sulfur Oxides _______________ Greenhouse gases that cause difficulty breathing ___________________ Causes acid precipitation _____________________ Ex: CO and CO2 Greenhouse gases ____________________________ Some are related to photochemical smog and greenhouse gases

Ozone Tropospheric Ozone- Vs. Stratospheric Ozone- ________________________________ _________________________________ Vs. Stratospheric Ozone-

Sources of Outdoor Air Pollution Two main sources 1. _____________ 2. _____________ Intentional forest fires is also high

Urban Air Pollution Photochemical Smog formed by chemical reactions involving sunlight, nitrogen oxide, and hydrocarbons

Formation of Photochemical Smog

Sources of Smog in Los Angeles

Effects of Air Pollution Low level exposure Irritates eyes Causes inflammation of respiratory tract Can develop into chronic respiratory diseases

Children and Air Pollution Greater health threat to children than adults _________________________________ ___________________________________

Controlling Air Pollution Without Electrostatic precipitator With Electrostatic precipitator

Controlling Air Pollution Smokestacks with scrubbers Particulate material can also be controlled

The Clean Air Act 1970 Authorizes EPA to set limits on amount of specific air pollutants permitted Focuses on 6 pollutants: ________________ _________________

The Clean Air Act

Urban Air Quality

Other Ways to Improve Air Quality Reduce sulfur content in gasoline Require federal emission standards for all passenger vehicles Require emission testing for all vehicles

Ozone Depletion in Stratosphere Ozone Protects earth from UV radiation

Ozone Depletion in Stratosphere Ozone thinning/hole First identified in 1985 over Antarctica Caused by human-produced bromine and chlorine containing chemicals Ex: CFCs

Ozone Depletion in Stratosphere Hole over Antarctica requires 2 conditions: a mass of cold air that circulates around the southern polar region forms clouds which Cl and Br stick to Sunlight-speeds up the reaction in which Cl and Br break up ozone

Effects of Ozone Depletion Higher levels of UV-radiation hitting the earth ______________ May ________________ May ______________________________________

Recovery of Ozone Layer Montreal Protocol (1987) Reduction of CFCs Started using HCFCs (greenhouse gas) Full recovery will not occur until 2050

Acid Deposition Sulfur dioxide and nitrogen dioxide emissions react with water vapor in the atmosphere and form acids that return to the surface as either dry or wet deposition pH scale

How Acid Deposition Develops

Effects of Acid Deposition ______________________________

Acid Deposition and Forest Decline

Air Pollution Around the World Developing countries __________________________________________________________________________ Shenyang, China 5 worst cities in world Beijing, China; Mexico City, Mexico; Shanghai, China; Tehran, Iran; and Calcutta, India

Case-In-Point Air Pollution in Beijing and Mexico City Beijing (left) Mexico City (above)

Long Distance Transport of Air Pollutants Global Distillation Effect

Indoor Air Pollution Pollutants can be 5-100X greater than outdoors!

Ahhhhh Clean Car Smell Over sixty chemicals were identified inside the interiors of the four vehicles in this study. Ten Most Toxic Nissan Versa Chevy Aveo Scion xB Kia Rio Suzuki Forenza Kia Spectra 5 Subaru Forester Chevy Express Hyundai Accent Chevy Silverado Ten Least Toxic Chevy Cobalt Chrysler PT Cruiser Honda Odyssey Volvo V50 Suzuki Aerio Acura RDX BMW X3 Nissan Frontier Toyota Matrix Volvo S40 volatile organic chemicals (VOC’s) in a new minivan were over 35 times the health limit the day after its delivery 34