Chapter 19Chapter 19Air PollutionAir Pollution

Atmosphere as a ResourceAtmosphere as a Resource

Atmospheric CompositionAtmospheric Composition N: 78.08%N: 78.08% O: 20.95%O: 20.95% Ar: 0.93%Ar: 0.93% COCO22: 0.04%: 0.04%

Ecosystem servicesEcosystem services Blocks UV radiationBlocks UV radiation Moderates the climateModerates the climate Redistributes water Redistributes water

Air Pollution - TerminologyAir Pollution - Terminology

Air PollutionAir Pollution Chemicals added to the atmosphere by Chemicals added to the atmosphere by

natural events or human activities in high natural events or human activities in high enough concentrations to be harmful enough concentrations to be harmful

1.1. Primary Air PollutantPrimary Air Pollutant Harmful substance that is emitted Harmful substance that is emitted directlydirectly

into the atmosphere into the atmosphere

2.2. Secondary Air PollutantSecondary Air Pollutant Harmful substance Harmful substance formed in the formed in the

atmosphere atmosphere when a primary air pollutant when a primary air pollutant reacts with substances normally found in the reacts with substances normally found in the atmosphere or with other air pollutants atmosphere or with other air pollutants

Major Air PollutantsMajor Air Pollutants

Particulate MaterialParticulate Material

Thousands of solid or liquid particles Thousands of solid or liquid particles suspended in airsuspended in air Ex: soil particles, soot, lead, asbestos, Ex: soil particles, soot, lead, asbestos,

sea salt, and sulfuric acid droplets sea salt, and sulfuric acid droplets DangerousDangerous

toxic/toxic/carcinogeniccarcinogenic effects effects

Nitrogen and Sulfur OxidesNitrogen and Sulfur Oxides Nitrogen OxidesNitrogen Oxides

Greenhouse gases that cause difficulty breathing and Greenhouse gases that cause difficulty breathing and leads to photochemical smogleads to photochemical smog

Sulfur OxidesSulfur Oxides Causes acid precipitationCauses acid precipitation

Carbon OxidesCarbon Oxides Ex: CO and COEx: CO and CO22 Greenhouse gasesGreenhouse gases

HydrocarbonsHydrocarbons- ex: CH- ex: CH44- methane- methane Some are related to photochemical smog and Some are related to photochemical smog and

greenhouse gasesgreenhouse gases

OzoneOzone

Tropospheric Ozone-Tropospheric Ozone- Man- made pollutant Man- made pollutant Secondary air pollutantSecondary air pollutant Component of photochemical smogComponent of photochemical smog

VS.VS. Stratospheric Ozone-Stratospheric Ozone-

Sources of Outdoor Air Sources of Outdoor Air PollutionPollution Two main Two main

sourcessources1. Transportation1. Transportation

2. Industry2. Industry

Urban Air PollutionUrban Air Pollution

Smog- air pollution that reduces Smog- air pollution that reduces visibilityvisibility Photochemical SmogPhotochemical Smog

formed by chemical reactions involving formed by chemical reactions involving sunlight, nitrogen oxide, and hydrocarbons sunlight, nitrogen oxide, and hydrocarbons

Formation of Photochemical Formation of Photochemical SmogSmog

Sources of Smog in Los Sources of Smog in Los AngelesAngeles

Effects of Air PollutionEffects of Air Pollution

Greater health threat to Greater health threat to childrenchildren than adultsthan adults Air pollution can restrict lung Air pollution can restrict lung

developmentdevelopment Children breath more often than adultsChildren breath more often than adults

ScrubberScrubber

Electrostatic Electrostatic precipitatorprecipitator

Controlling Air Pollution- (particulate Controlling Air Pollution- (particulate matter) matter)

The Clean Air Act 1970The Clean Air Act 1970

Authorizes EPA to set limits on Authorizes EPA to set limits on amount of specific air pollutants amount of specific air pollutants permittedpermitted

Focuses on 6 pollutants:Focuses on 6 pollutants: lead, particulate matter, sulfur dioxide, lead, particulate matter, sulfur dioxide,

carbon monoxide, nitrogen oxides, and carbon monoxide, nitrogen oxides, and ozoneozone

The Clean Air ActThe Clean Air Act

Urban Air QualityUrban Air Quality

Other Ways to Improve Air Other Ways to Improve Air QualityQuality Reduce sulfur content in gasolineReduce sulfur content in gasoline Require federal emission standards Require federal emission standards

for all passenger vehiclesfor all passenger vehicles Require emission testing for all Require emission testing for all

vehiclesvehicles

Ozone Depletion in Ozone Depletion in StratosphereStratosphere Ozone Protects earth from UV Ozone Protects earth from UV

radiationradiation

Ozone Depletion in Ozone Depletion in StratosphereStratosphere Ozone thinning/holeOzone thinning/hole

First identified in First identified in 1985 over Antarctica1985 over Antarctica

Caused by Caused by human-produced human-produced

bromine and bromine and chlorine containing chlorine containing chemicalschemicals

Ex: CFCsEx: CFCs

Effects of Ozone DepletionEffects of Ozone Depletion

Higher levels of UV-Higher levels of UV-radiation hitting the radiation hitting the earthearth Eye cataractsEye cataracts Skin cancer (right)Skin cancer (right) Weakened immunityWeakened immunity

May disrupt May disrupt ecosystemsecosystems

May damage crops May damage crops and forestsand forests

Recovery of Ozone LayerRecovery of Ozone Layer

Montreal Protocol (1987)Montreal Protocol (1987) Reduction of CFCsReduction of CFCs Started using HCFCs (greenhouse gas)Started using HCFCs (greenhouse gas)

Full recovery will not occur until 2050Full recovery will not occur until 2050

Acid DepositionAcid Deposition

Effects of Acid DepositionEffects of Acid Deposition

Declining Declining Aquatic Animal Aquatic Animal PopulationsPopulations

Thin-shelled Thin-shelled eggs prevent eggs prevent bird bird reproductionreproduction Calcium is Calcium is

unavailable in unavailable in acidic soilacidic soil

Forest declineForest decline

Acid Deposition and Forest Acid Deposition and Forest DeclineDecline

Air Pollution Around the Air Pollution Around the WorldWorld Air quality is deteriorating rapidly in Air quality is deteriorating rapidly in developing countries developing countries

5 worst cities in world5 worst cities in world Beijing, China; Mexico City, Mexico; Beijing, China; Mexico City, Mexico;

Shanghai, China; Tehran, Iran; and Shanghai, China; Tehran, Iran; and Calcutta, India Calcutta, India

Air pollution can travel thousands of Air pollution can travel thousands of milesmiles

Indoor Air PollutionIndoor Air Pollution

Pollutants can Pollutants can be 5-100X be 5-100X greater than greater than outdoors!outdoors!

Ahhhhh Clean Car SmellAhhhhh Clean Car Smell Ten Most ToxicTen Most Toxic

Nissan Versa Nissan Versa Chevy Aveo Chevy Aveo Scion xB Scion xB Kia Rio Kia Rio Suzuki Forenza Suzuki Forenza Kia Spectra 5 Kia Spectra 5 Subaru Forester Subaru Forester Chevy Express Chevy Express Hyundai Accent Hyundai Accent Chevy SilveradoChevy Silverado

Ten Least ToxicTen Least ToxicChevy Cobalt Chevy Cobalt Chrysler PT Cruiser Chrysler PT Cruiser Honda Odyssey Honda Odyssey Volvo V50 Volvo V50 Suzuki Aerio Suzuki Aerio Acura RDX Acura RDX BMW X3 BMW X3 Nissan Frontier Nissan Frontier Toyota Matrix Toyota Matrix Volvo S40Volvo S40

Over sixty chemicals were identified inside the interiors of the four vehicles in this study.

volatile organic volatile organic chemicals (VOC’s) in a chemicals (VOC’s) in a new minivan were over new minivan were over 35 times the health limit 35 times the health limit the day after its delivery the day after its delivery