urban air quality. gaseous composition of the atmospheregaseous composition of the atmosphere

Urban Air QualityUrban Air Quality


• Gaseous Composition of the Gaseous Composition of the AtmosphereAtmosphereGas % Volume PPMN2 78.1 780,840O2 21.0 209,460Ar 0.93 9,340

CO2 0.035 350CO 0.00003 0.3Ne 0.0018 18He 0.00052 5.2

CH4 0.00014 1.4N2O 0.00005 0.5O3 0.000007 0.07


• Sources of Urban Air PollutantsSources of Urban Air Pollutants– Stationary SourcesStationary Sources– Mobile SourcesMobile Sources– Non-Point (Area) Non-Point (Area)


• Types of Urban Air PollutantsTypes of Urban Air Pollutants– Primary Pollutant - a pollutant Primary Pollutant - a pollutant

that directly enters the air as a that directly enters the air as a result of natural events or human result of natural events or human activitiesactivities


• Types of Urban Air PollutantsTypes of Urban Air Pollutants– Examples of Primary PollutantsExamples of Primary Pollutants

•Carbon monoxide (CO)Carbon monoxide (CO)

•Carbon dioxide (COCarbon dioxide (CO22))

•Sulfur dioxide (SOSulfur dioxide (SO22))

•Nitric oxide (NO)Nitric oxide (NO)•Hydrocarbons (HCs)Hydrocarbons (HCs)•Suspended Particulate Matter Suspended Particulate Matter

(SPMs)(SPMs)


• Types of Urban Air PollutantsTypes of Urban Air Pollutants– Secondary Pollutant - a pollutant Secondary Pollutant - a pollutant

that is formed in the air through that is formed in the air through chemical reactions between or chemical reactions between or among primary pollutants or among primary pollutants or between primary pollutants and between primary pollutants and other gases in the atmosphereother gases in the atmosphere


• Types of Urban Air PollutantsTypes of Urban Air Pollutants– Examples of Secondary PollutantsExamples of Secondary Pollutants

•Nitrogen Dioxide (NONitrogen Dioxide (NO22))

•Sulfur Trioxide (SOSulfur Trioxide (SO33))

•Nitric Acid (HNONitric Acid (HNO33))

•Hydrogen Peroxide (HHydrogen Peroxide (H22OO22))

• Tropospheric Ozone (OTropospheric Ozone (O33))

•Nitrate (NONitrate (NO33))

•Peroxyacetyl Nitrates (PANs)Peroxyacetyl Nitrates (PANs)


• Chemical Classes of Urban Air Chemical Classes of Urban Air PollutantsPollutants– Carbon OxidesCarbon Oxides

•COCO

•COCO22

– Sulfur OxidesSulfur Oxides•SOSO

•SOSO22


• Chemical Classes of Urban Air Chemical Classes of Urban Air PollutantsPollutants– Nitrogen OxidesNitrogen Oxides

•NO (nitric oxide)NO (nitric oxide)

•NONO2 2 (nitrogen dioxide)(nitrogen dioxide)

•NN22O (nitrous oxide - “laughing gas!”)O (nitrous oxide - “laughing gas!”)

– Sulfur OxidesSulfur Oxides•SOSO22 (sulfur dioxide) (sulfur dioxide)

•SOSO33 (sulfur trioxide) (sulfur trioxide)


• Chemical Classes of Urban Air Chemical Classes of Urban Air PollutantsPollutants– Volatile Organic Compounds Volatile Organic Compounds

(VOCs)(VOCs)•CHCH4 4 (methane)(methane)

•CC66HH66 (benzene) (benzene)

•CFCs (chlorofluorohydrocarbons)CFCs (chlorofluorohydrocarbons)

•CHCH220 (formaldehydr)0 (formaldehydr)


• Chemical Classes of Urban Air Chemical Classes of Urban Air PollutantsPollutants– Suspended Particulate Matter Suspended Particulate Matter

(SPMs)(SPMs)•DustDust•SootSoot•AsbestosAsbestos•PollenPollen


• Chemical Classes of Urban Air Chemical Classes of Urban Air PollutantsPollutants– Photochemical OxidantsPhotochemical Oxidants

•OO33 (tropospheric ozone) (tropospheric ozone)

•HH22OO22 (hydrogen peroxide) (hydrogen peroxide)

•PANs (peroxyacetylnitrates) PANs (peroxyacetylnitrates)


• Chemical Classes of Urban Air Chemical Classes of Urban Air PollutantsPollutants– Radioactive SubstancesRadioactive Substances

•RnRn222222 (Radon) (Radon)

– Toxic MetalsToxic Metals•Pb - LeadPb - Lead•Cd - CadmiumCd - Cadmium•Hg - MercuryHg - Mercury•Ar - ArsenicAr - Arsenic


• Regulation of Urban Air Regulation of Urban Air PollutionPollution– Clean Air ActsClean Air Acts

•Passed in 1970, 1977, 1990Passed in 1970, 1977, 1990• Enacted federal air pollution Enacted federal air pollution

regulations that are enforced by regulations that are enforced by each stateeach state

• Established Established National Ambient Air National Ambient Air Quality Standards (NAAQS)Quality Standards (NAAQS)


• Regulation of Urban Aair Regulation of Urban Aair PollutionPollution– NAAQSNAAQS

•7 Criteria Pollutants7 Criteria Pollutants– SPMsSPMs– Sulfur OxidesSulfur Oxides– Carbon MonoxideCarbon Monoxide– Nitrogen OxidesNitrogen Oxides– Tropospheric OzoneTropospheric Ozone– VOCsVOCs– LeadLead


• Regulation of Urban Aair Regulation of Urban Aair PollutionPollution– NAAQSNAAQS

•Primary NAAQS - standards Primary NAAQS - standards established to protect human healthestablished to protect human health

•Secondary NAAQS - standards Secondary NAAQS - standards established to protect all organismsestablished to protect all organisms

•Nonattainment Area - any area that Nonattainment Area - any area that does not meet primary or secondary does not meet primary or secondary NAAQS for a criteria pollutant NAAQS for a criteria pollutant


National Ambient Air Quality National Ambient Air Quality StandardsStandards

Carbon MonoxideCarbon Monoxide9 ppm over 8-hr period, not 9 ppm over 8-hr period, not to to be exceeded more than be exceeded more than once a once a year; 35-ppm for year; 35-ppm for 1-hr period1-hr period

Ozone Ozone 0.12 ppm for 1-hr period, not 0.12 ppm for 1-hr period, not to to be exceeded more than be exceeded more than once once per yearper year


National Ambient Air Quality National Ambient Air Quality StandardsStandards

Sulfur DioxideSulfur Dioxide 0.03 ppm annual 0.03 ppm annual average; 0.14 average; 0.14 ppm for 24-ppm for 24-hr period, not to be hr period, not to be exceeded more than once per exceeded more than once per

yearyear

Nitrogen OxidesNitrogen Oxides 0.05 ppm annual average0.05 ppm annual average


• Regulation of Urban Air PollutionRegulation of Urban Air Pollution– Criteria PollutantsCriteria Pollutants

• Tropospheric OzoneTropospheric Ozone– Source:Source: Chemical reactions between VOCs, Chemical reactions between VOCs,

nitrogen oxides, and sunlightnitrogen oxides, and sunlight– Health EffectsHealth Effects: Reduced lung function; asthma; : Reduced lung function; asthma;

congestioncongestion– Environmental ImpactsEnvironmental Impacts: Reduced visibility; : Reduced visibility;

plant damage, reduced photosynthesis and plant damage, reduced photosynthesis and nutrient uptake, crop destruction; forest nutrient uptake, crop destruction; forest diebacksdiebacks

– Property DamageProperty Damage: Rubber; plastics: Rubber; plastics



•Carbon MonoxideCarbon Monoxide– Source:Source: Incomplete combustion of fossil Incomplete combustion of fossil

fuelsfuels– Health EffectsHealth Effects: Reduced oxygen levels; : Reduced oxygen levels;

impaired visual perception; reduced lung impaired visual perception; reduced lung function; asthma; congestionfunction; asthma; congestion

– Environmental ImpactsEnvironmental Impacts: Reduced visibility; : Reduced visibility; plant damageplant damage

– Property DamageProperty Damage: Rubber; plastics: Rubber; plastics



•Nitrogen and Sulfur OxidesNitrogen and Sulfur Oxides– Source:Source: Incomplete combustion of fossil Incomplete combustion of fossil

fuelsfuels– Health EffectsHealth Effects: Lung damage; respiratory : Lung damage; respiratory

illnessesillnesses– Environmental ImpactsEnvironmental Impacts: Acid deposition; : Acid deposition;

plant damage; photochemical smog; crop plant damage; photochemical smog; crop destructiondestruction

– Property DamageProperty Damage: Enhanced chemical : Enhanced chemical weatheringweathering



•SPMsSPMs– Source:Source: Incomplete combustion of fossil Incomplete combustion of fossil

fuels; agriculture; unpaved roadsfuels; agriculture; unpaved roads– Health EffectsHealth Effects: Lung damage; respiratory : Lung damage; respiratory

illnessesillnesses– Environmental ImpactsEnvironmental Impacts: Reduced visibility : Reduced visibility

(haze(haze– Property DamageProperty Damage: Discoloration of clothing : Discoloration of clothing

and structuresand structures


• Regulation of Urban Air Regulation of Urban Air PollutionPollution– Criteria PollutantsCriteria Pollutants

• LeadLead– Source:Source: Leaded gasoline; lead paint; Leaded gasoline; lead paint;

smelters; lead-acid batteriessmelters; lead-acid batteries– Health EffectsHealth Effects: Damage to nervous system; : Damage to nervous system;

cancer; mental retardation; digestive cancer; mental retardation; digestive disordersdisorders

– Environmental ImpactsEnvironmental Impacts: Harmful to wildlife: Harmful to wildlife


• Photochemical (Brown-Air) Photochemical (Brown-Air) Smog Smog – A mixture of primary and A mixture of primary and

secondary pollutants (mostly secondary pollutants (mostly tropospheric ozone) formed tropospheric ozone) formed under the influence of sunlightunder the influence of sunlight


• Photochemical (Brown Air) Photochemical (Brown Air) SmogSmog– Factors of FormationFactors of Formation

• Topography Topography • Local climateLocal climate•Population densityPopulation density•Amount of industryAmount of industry• Industrial fuel types Industrial fuel types



• Topography Topography – Hills and mountains reduce air flow in Hills and mountains reduce air flow in

valleys and allow pollutant levels to build valleys and allow pollutant levels to build up at ground levelup at ground level

– Buildings in cities slow wind speed, Buildings in cities slow wind speed, reducing dilution and dispersal of reducing dilution and dispersal of pollutantspollutants


• Photochemical (Brown Air) SmogPhotochemical (Brown Air) Smog– Factors of FormationFactors of Formation

• Topography Topography – Thermal InversionThermal Inversion

» Sunny climateSunny climate» Light windsLight winds» Mountains on three sides, ocean on the Mountains on three sides, ocean on the

otherother» High population densityHigh population density» High motor vehicle usageHigh motor vehicle usage» High industrialization using fossil fuelsHigh industrialization using fossil fuels


• Photochemical (Brown Air) SmogPhotochemical (Brown Air) Smog– Factors of FormationFactors of Formation

• TopographyTopography– Los Angeles BasinLos Angeles Basin

» Hemmed in by mountains on 3 sides and Hemmed in by mountains on 3 sides and ocean on the otherocean on the other

» 14 million people; 23 million motor 14 million people; 23 million motor vehiclesvehicles

» Frequent thermal inversions Frequent thermal inversions » Air pollution capital of U.S.Air pollution capital of U.S.



• Local ClimateLocal Climate– Areas with high average annual Areas with high average annual

precipitation and wind speeds have less precipitation and wind speeds have less smog due to dilution and dispersalsmog due to dilution and dispersal


• Industrial (Gray-Air) SmogIndustrial (Gray-Air) Smog– Mixture of sulfur dioxide, suspended Mixture of sulfur dioxide, suspended

droplets of sulfuric acid, and SPMsdroplets of sulfuric acid, and SPMs

– Found mostly in LDCs where coal Found mostly in LDCs where coal and heavy oils are burnedand heavy oils are burned•ChinaChina•UkraineUkraine• Eastern EuropeEastern Europe


• Acid DepositionAcid Deposition– The falling of acids and acid-The falling of acids and acid-

forming compounds from the forming compounds from the atmosphere to the Earth’s atmosphere to the Earth’s surfacesurface


• Acid DepositionAcid Deposition– ComponentsComponents

•Primary PollutantsPrimary Pollutants– Nitrogen Oxides (NOx)Nitrogen Oxides (NOx)– Sulfur Oxides (SOx)Sulfur Oxides (SOx)

Secondary PollutantsSecondary Pollutants– Nitric Acid (HNONitric Acid (HNO33))

– Sulfuric Acid (HSulfuric Acid (H22SOSO44))


• Acid DepositionAcid Deposition– Acid SourcesAcid Sources

•Coal-burning power plantsCoal-burning power plants•SmeltersSmelters• FactorsFactors•Urban areasUrban areas


• Acid DepositionAcid Deposition– Mechanisms of Acid DepositionMechanisms of Acid Deposition

•Dry DepositionDry Deposition•PrecipitationPrecipitation


• Acid DepositionAcid Deposition– Environmental Impacts of Acid Environmental Impacts of Acid

DepositionDeposition•Regional environmental problem Regional environmental problem

because acids remain in atmosphere because acids remain in atmosphere for only a few daysfor only a few days

• Environmental impacts depend on Environmental impacts depend on buffering capacitybuffering capacity of soils of soils



DepositionDeposition• Ecosystems most harmed by acid Ecosystems most harmed by acid

deposition are those with thin soils deposition are those with thin soils that lack natural bufferingthat lack natural buffering



DepositionDeposition•Damage to materials Damage to materials

– StatuesStatues– BuildingsBuildings– MetalsMetals– Car finishesCar finishes



DepositionDeposition•Human HealthHuman Health

– BronchitisBronchitis– AsthmaAsthma



DepositionDeposition•Aquatic EcosystemsAquatic Ecosystems

– Acid ShockAcid Shock– Aluminum toxicityAluminum toxicity

» Stimulates excessive mucus Stimulates excessive mucus formation leading to asphyxiation of formation leading to asphyxiation of fish by clogging their gillsfish by clogging their gills




– Formation of methylmercuryFormation of methylmercury» Highly toxicHighly toxic» Soluble in fatty tissue of animalsSoluble in fatty tissue of animals» BioaccumulationBioaccumulation




– Fun FactsFun Facts» 16,000 lakes in Norway and Sweden 16,000 lakes in Norway and Sweden

contain no fishcontain no fish» 9,000 lakes in U.S. are threatened 9,000 lakes in U.S. are threatened

with excess acidity (most in the Great with excess acidity (most in the Great Lakes!)Lakes!)



DepositionDeposition• Terrestrial EcosystemsTerrestrial Ecosystems

– Most damage when pH < 5.1Most damage when pH < 5.1– Damage to tree foliage bathed in acidic Damage to tree foliage bathed in acidic

fogfog



DepositionDeposition• Terrestrial EcosystemsTerrestrial Ecosystems

– Increased susceptibility to various stressorsIncreased susceptibility to various stressors» Cold temperaturesCold temperatures» DiseasesDiseases» InsectsInsects» DroughtDrought» Depletion of plant nutrientsDepletion of plant nutrients


• Urban ClimateUrban Climate– Cities are generally warmer, Cities are generally warmer,

rainier, foggier, and cloudier than rainier, foggier, and cloudier than suburbs or rural areassuburbs or rural areas


• Urban ClimateUrban Climate– Cities generate enormous Cities generate enormous

amounts of heatamounts of heat•AutomobilesAutomobiles• FactoriesFactories• FurnacesFurnaces• Lights Lights •Air conditionersAir conditioners•PeoplePeople


• Urban ClimateUrban Climate– Urban Heat Island - the buildup of Urban Heat Island - the buildup of

heat in the atmosphere above an heat in the atmosphere above an urban areaurban area


• Indoor Air PollutionIndoor Air Pollution– SourcesSources

•CombustionCombustion•Building materials and furnishingsBuilding materials and furnishings•Household cleaning productsHousehold cleaning products•Personal care productsPersonal care products•Central heating/cooling systemsCentral heating/cooling systems•Outside sources - radon gas and Outside sources - radon gas and

pesticidespesticides•Poor ventilationPoor ventilation


• Indoor Air PollutionIndoor Air Pollution– Most Dangerous Indoor Air Most Dangerous Indoor Air

PollutantsPollutants• FormaldehydeFormaldehyde•AsbestosAsbestos•Cigarette smokeCigarette smoke•Radon-222Radon-222• FiberglassFiberglass


• Indoor Air PollutionIndoor Air Pollution– Leading cause of cancerLeading cause of cancer– High-risk health problem for humansHigh-risk health problem for humans– ““Sick Building Syndrome”Sick Building Syndrome”

•CoughingCoughing•SneezingSneezing•NauseaNausea•Burning eyesBurning eyes• Flulike symptomsFlulike symptoms


• Indoor Air PollutionIndoor Air Pollution– ““Sick Building Syndrome”Sick Building Syndrome”

•17% of all buildings in U.S. are 17% of all buildings in U.S. are “sick”, including the U.S. EPA “sick”, including the U.S. EPA headquarters in Washington, DCheadquarters in Washington, DC

•Mineral fibers falling from ceiling Mineral fibers falling from ceiling tiles are main culprittiles are main culprit

urban air quality. gaseous composition of the atmospheregaseous composition of the atmosphere

Documents

urban air quality slide

sulfur trioxide slide

atmosphere slide

arsenic slide

formaldehydr slide

carbon dioxide

sulfur trioxideso

sulfur dioxideso