Chapter 20Chapter 20Air PollutionAir Pollution

Atmosphere as a ResourceAtmosphere as a Resource

Atmospheric CompositionAtmospheric Composition __: 78.08%__: 78.08% __: 20.95%__: 20.95% __: 0.93%__: 0.93% __: 0.04%__: 0.04%

Ecosystem servicesEcosystem services Blocks _________Blocks _________ Moderates _________Moderates _________ 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 ______________________________________________________________________________________________

___________________________________ ___________________________________

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

atmosphere atmosphere ______________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

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: Ex:

______________________________________________________________________________________________________________________________________________

DangerousDangerous ________________________________________________________________________

Nitrogen and Sulfur OxidesNitrogen and Sulfur Oxides ______________________________

Greenhouse gases that cause difficulty breathingGreenhouse gases that cause difficulty breathing ______________________________________

Causes acid precipitationCauses acid precipitation __________________________________________

Ex: CO and COEx: CO and CO22 Greenhouse gasesGreenhouse gases

________________________________________________________ Some are related to photochemical smog and Some are related to photochemical smog and

greenhouse gasesgreenhouse gases

OzoneOzone

Tropospheric Ozone-Tropospheric Ozone- ________________________________________________________________ ________________________________________________________________ __________________________________________________________________

Vs.Vs. Stratospheric Ozone-Stratospheric Ozone-

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

sourcessources1. _____________1. _____________

2. _____________2. _____________

Urban Air PollutionUrban Air Pollution

Photochemical SmogPhotochemical Smog formed by chemical reactions involving formed by chemical reactions involving

sunlight, nitrogen oxide, and sunlight, nitrogen oxide, and hydrocarbons 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 Low level exposureLow level exposure

Irritates eyesIrritates eyes Causes inflammation of respiratory tractCauses inflammation of respiratory tract

Can develop into chronic respiratory Can develop into chronic respiratory diseasesdiseases

Children and Air PollutionChildren and Air Pollution

Greater health threat to children Greater health threat to children than adultsthan adults __________________________________________________________________ ______________________________________________________________________

Without Without Electrostatic Electrostatic precipitatorprecipitator

With Electrostatic With Electrostatic precipitatorprecipitator

Controlling Air Pollution Controlling Air Pollution

Controlling Air PollutionControlling Air Pollution

Smokestacks with Smokestacks with scrubbers scrubbers

Particulate material Particulate material can also be controlledcan also be controlled

The Clean Air Act 1970The Clean Air Act 1970

Authorizes EPA to set limits on amount of Authorizes EPA to set limits on amount of specific air pollutants permittedspecific air pollutants permitted

Focuses on 6 pollutants:Focuses on 6 pollutants: ________________________________ __________________________________ __________________________________ __________________________________ __________________________________ __________________________________

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

Ozone Depletion in Ozone Depletion in StratosphereStratosphereHole over Antarctica requires 2 Hole over Antarctica requires 2

conditions:conditions:1.1. a mass of cold air that circulates a mass of cold air that circulates

around the southern polar region forms around the southern polar region forms clouds which Cl and Br stick toclouds which Cl and Br stick to

2.2. Sunlight-speeds up the reaction in Sunlight-speeds up the reaction in which Cl and Br break up ozonewhich Cl and Br break up ozone

Effects of Ozone DepletionEffects of Ozone Depletion

Higher levels of UV-Higher levels of UV-radiation hitting the radiation hitting the earthearth ____________________________ ____________________________ ____________________________

May ________________May ________________ May May

____________________________________________________________________________

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

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

pH scalepH scale

How Acid Deposition How Acid Deposition DevelopsDevelops

Effects of Acid DepositionEffects of Acid Deposition

____________________________________________________________

____________________________________________________________

____________________________________________________________

Acid Deposition and Forest Acid Deposition and Forest DeclineDecline

Air Pollution Around the Air Pollution Around the WorldWorld Developing countries Developing countries

____________________________________________________________________________________________________________________________________________________

Shenyang, ChinaShenyang, China 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

Case-In-Point Air Pollution in Case-In-Point Air Pollution in Beijing and Mexico CityBeijing and Mexico City

Beijing (left)Beijing (left) Mexico City (above)Mexico City (above)

Global Distillation EffectGlobal Distillation Effect

Long Distance Transport of Long Distance Transport of Air PollutantsAir Pollutants

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