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					Atomosphere and Air quality
            Core Case Study
    South Asia’s Massive Brown Cloud
► Watch   this video about South Asia's Brown
  Cloud
► Also bad news for other parts of the world
   25% particulate matter   Found in Los Angeles on
   77% black carbon         some days can be traced to
                             coal-fired power plants,
   33% mercury              smelters, diesel trucks and
                             dust storms from
                             deforestation in China.
           The Atmosphere
► What is the “atmosphere?”
► What is atmospheric pressure?
► What are the layers to the atmosphere?
Atmospheric Profile
                                                                                               The earth’s atmosphere:




                                            Atmospheric pressure decreases with altitude
                                                                                           Divided into layers caused by
                                                                                           differences in temperature and




          Density decreases with altitude
                                                                                                incoming solar energy
Atmosphere Profile
                       Air Pollution
► Presence  of chem in atmosphere at concen
  high enough to harm organisms, ecosystems or
  materials
► Natural Sources
   Dust, wildfires, volcanic eruptions, VOCs from
    plants
► Human     Sources
   Industrialized or urban areas
   Burning of fossil fuels
   Stationary vs. mobile sources
     ► Which    is responsible for greater amount of air pollution varies
      by city
         Pollutants Can Combine
► Primary   vs. Secondary Pollutants
► Urban areas worse than rural, but prevailing
  winds spread to rural
► Good News: outdoor air quality improved
  greatly for developed countries
► Bad News: 1.1B live in urban areas
  w/unhealthy air
   mostly developing countries w/no regulations
► Air   pollution is a global problem
                     Primary Pollutants

                       CO CO2                   Secondary Pollutants
                     SO2 NO NO2
                     Most hydrocarbons                SO3
                     Most suspended particles     HNO3 H2SO4
                                                 H2O2 O3 PANs
                                           Most NO3− and SO42− salts
Sources    Natural       Stationary




          Mobile
        Major Outdoor Air Pollutants

► CO
   Colorless, odorless, highly toxic
   Result of incomplete combustion
   Vehicle exhaust, slash & burn, tobacco smoke, open
    fires, inefficient stoves
   CO poisoning, heart attack, asthma, emphysema
► CO2
   Colorless, odorless, not toxic unless at high
    concentrations without oxygen
   93% is natural, 7% human generated
   Fossil fuels, deforestation  climate change
   Nitrogen Oxides & Nitric Acid
► NOx
   Colorless, forms from reaction of N2 + O2 at high
    temps (like in an engine, coal furnace)
   Leads to acid deposition
     ► NO   + O2  NO2 + H2O  HNO3 + NO3- salt
   Component of photochemical smog – NO & NO2
► N2O
   Greenhouse gas
   Fertilizers, animal waste, burning fossil fuels
► Eye,nose, throat irritation
  asthma, bronchitis
  more susceptibel to disease
► Reduced visibility
                 SO2 & H2SO4
► SO2
   Colorless, bad odor
   ½ natural, 2/3 human caused, mostly burning coal
► Aerosols
   Sulfuric acid and sulfate salts
   SO2 + O2  SO3 + H2O  H2SO4 (acid deposition)
► Reduced   visibility
► Aggravate respiratory problems
  Damage crops, leach soils, aquatic acidifcation
  Corrode metals, fade paint, damage human
  materials
                              SPMs
►   Particulate matter and liquid
    droplets that remain suspended
    in atmosphere
►   38% human caused – coal
    burning, industry, vehicles, road
    construction, tobacco smoke
►   Fine and ultrafine – biggest
    concerns
►   Aggravate resp problems
►   Toxic SPM (ex: cadmium) linked
    to mutations, cancer
►   Corrodes materials, reduced
    visibility
►   EPA: 60-70,000 die/yr
                    Ozone
► Component   of photochemical smog
► Good in stratosphere, bad in troposphere
   We’re adding to tropo, reducing in strato
        resp,
► Irritates
  Damages plants
  Damages rubber, fabrics, paints
                    VOCs
► “VolatileOrganic Compounds”
► Organic, gaseous, mostly hydrocarbons
   EX: isoprene C3H8, terpenes C10H15, methane
          dry-cleaning fluids, gasoline
► Solvents,
  component, plastics, drugs, rubber, etc.
   Benzene C6H6, vinyl chloride, TCE
   Leukemia, dizziness, unconcsciousness, death
               CASE STUDY: Lead
►   Neurotoxin – palsy, paralysis, blindness, retardation, death,
    lower IQ, attention disorders & hyperactivity
►   Children & unborn esp. susceptible
►   Good News: 1976-2000 % US children ages 1-5 with
    unsafe blood Pb levels dropped 85%  2.2%
      Due to banning of leaded gasoline (’76) and lead paint
       (’70)
►   Bad News: still 31,000 above safety limit
      Lead paint chips, lead dust old bldgs, lead pipes
►   2007 Chinese toy recalls, lipsticks
►   Developing countries worse (still leaded gas)
           SOLUTIONS
                     Lead Poisoning
Prevention                            Control
Phase out leaded                      Replace lead pipes and
gasoline worldwide                    plumbing fixtures
                                      containing lead solder
Phase out waste                       Remove leaded paint and
incineration                          lead dust from older
                                      houses and apartments
Ban use of lead solder
Ban use of lead in                    Sharply reduce lead
computer and TV                       emissions from
monitors                              incinerators
                                      Remove lead from TV sets
Ban lead glazing for                  and computer monitors
ceramicware used to                   before incineration or land
serve food                            disposal
                                      Test for lead in existing
Ban candles with lead                 ceramicware used to
cores                                 serve food

Test blood for lead by                Test existing candles for
age 1                                 lead
                                      Wash fresh fruits and
                                      vegetables
               Gray Air Smog
► Industrial smog
► Mostly SO2, H2SO4 vapor, SPMs
► Mostly from burning coal
► SPMs and salts create gray color
► Big problem in developing countries with no
  pollution controls
► Urban areas of China & India (China worst)
       Ammonium sulfate [(NH4)2SO4]

Ammonia (NH3)

         Sulfuric acid (H2SO4)

Water vapor (H2O)                     Carbon monoxide (CO)
                                               and
        Sulfur trioxide (SO 3 )        carbon dioxide (CO2)

Oxygen (O2)

          Sulfur dioxide (SO2)


                          Burning coal and oil

                                Oxygen (O2)




                Sulfur (S) in             Carbon (C) in
                coal and oil              coal and oil
          Photochemical Smog
► Primary & secondary pollutants + U.V.
► Formation (next slide)
► Photochemical Oxidants
   React with compounds in atmosphere or lungs
    that normally are not oxidized by reaction with
    oxygen
   NO2, O3, PANs
► Worse on hotter days – higher O3 & UV
► Most common in cities with lots of cars and
  sunny warm dry climates
   EX: LA, Denver, Salt Lake City
                PANS and other pollutants
    Volatile organic
    compounds (VOCs)
                         Ozone (O3)

         Oxygen (O2)
                    Nitric oxide (NO)
                            +
                    Oxygen atom (O)
                    Water
                    vapor
       Hydrocarbons (H O)       UV radiation
                       2
Peroxyacyl
nitrates            Nitrogen dioxide (NO2)
(PANs)
          Oxygen (O2)
                       Nitric oxide (NO)
         Oxygen (O2)           Burning fossil fuels




                 Nitrogen (N) in fossil fuel
       Factors Affecting Outdoor Air
                 Pollution
Reduce                       Increase
Settling                    Bldgs block wind
Rain & snow                 Hills & mountains
Sea spray                   High temps promote
Wind dilution               rxns
Chem rxns                   VOCs from certain trees
  –Formation of H2SO4          and plants (Ex: some
  droplets that settle out     oaks)
                             “Grasshopper Effect”-
                               VOCs to poles
            Thermal Inversions

NORMALLY                   INVERSION
Sun warms air @ surface    Cool, dense air moves in
                           covering the area
Air expands & rises        Warm air moves in & traps
                           cool below
Carries pollutants into    Upward current prevented
troposphere
Colder, denser air moves in Smog, pollutants trapped &
                            build up over area
Mixing                      No mixing
             Diagram:
Normal Air Patter vs.Thermal Inversion
 2 Examples of Thermal Inversions


Warmer air                                   Descending warm air mass

Inversion layer                                    Inversion layer


                                           Sea breeze
                  Increasing
                  altitude


                  Decreasing temperature
                      Inversions
► May last hours or days  very toxic
► Susceptible Areas:
   In valley, surrounded by mtns, cloudy & cold
     ► Clouds block sunlight from heating
     ► Mtns block wind

   Lots of cars, light winds, mtns on 3 sides, ocean on
    4th side
     ► Conditionsgood for photochem smog PLUS ideal for inversions
     ► Mtns prevent clearing
     ► EX: LA
              Acid Deposition
► Regional    problem
   Tall smokestacks
   H2SO4, HNO3, sulfate & nitrate salts
   Prevailing winds carry
► Deposition
   Wet vs. Dry
    ►Forms
    ►Wet- falls 4-14 days after release, distantly
     downwind
    ►Dry – falls 2-3 days near emission source
► Downwind   areas hurt
► Soil can buffer
   Ca+, Mg+2 (limestone)
   Thin soils can’t buffer well, if at all
► Origin   and area affected - not the same
   EX: >50% acid deposition of SE Canada comes
    from OH, IN, PA, IL, MO, WV, TN coal & oil
    power plants
   EX: Midwest coal plants cause Eastern rain to
    be 10x more acidic
Potential problem areas because of sensitive soils

Potential problem areas because of air pollution:
emissions leading to acid deposition
Current problem areas (including lakes and rivers)
     Effects of Acid Deposition
► Contributes  to resp diseases
► Damages materials (statues, monuments,
  buildings, car paint)
► Particles decrease visibility
► Leach toxic metals (Ex: Pb, Hg) into
  groundwater or lakes/oceans
   Problem for drinking water or contaminated fish
    we eat
          Emissions



            SO2 NOx
  Acid
            HO
  deposition 2 2 O3
            PANs Others

          Direct damage to             Reduced            Increased
          leaves and bark              photosynthesis     susceptibility to
                                       and growth         drought, extreme
                                                          cold, insects,
                                                          mosses, and
                                                          disease organisms




                      Soil acidification                                  Tree death



              Leaching              Release      Root       Reduced nutrient
              of soil     Acids     of toxic     damage     and water uptake
              nutrients             metal ions

Lake


           Groundwater
                                                                               Fig. 18-14a, p. 481
► Aquatic       Ecosystems
   pH too low for fish (≤ 4.5)
   Leached Al3+ triggers excessive mucus formation 
    asphyxiation
► Damages          Crops
   Soil pH <5.1
   Reduces productivity
   Hampers buffering capacity of soil
► Forests
     Leach essential nutrients from soil
     Release toxic metals
     Weakens trees – more susceptible to disease/pests
     Mountaintop areas more susceptible
       ► Thin soil, little to no buffering capacity
       ► Acidic fog bathes area
 SOLUTIONS
        Acid Deposition
Prevention                 Cleanup
Reduce coal use            Add lime to
                           neutralize acidified
Burn low-sulfur coal       lakes
Increase natural gas use   Add phosphate
Increase use of            fertilizer to
renewable energy           neutralize acidified
resources                  lakes

Remove SO2
particulates and NOx
from smokestack gases
Remove NOx from motor
vehicular exhaust

Tax emissions of SO2
Reduce air pollution by
improving energy
efficiency
            Indoor Air Pollution
► Indoor   greater threat than outdoor
   EPA Studies indicate:
     ► Levels  of 11 common pollutants 2-5X higher inside than outside
     ► Traffic clogged areas – 18X higher in car
     ► Health risk magnified in developed countries – spend 70-98% of
       time indoors

► Since1990, EPA placed indoor air pollution at
 top of list of 18 sources of cancer risk
   6000 premature cancer deaths/yr
   Highest risk – smokers, children <5, elderly, sick,
    pregnant, resp/heart problems, some factory
    workers
       Chloroform                    Para-dichlorobenzene     Tetrachloroethylene
        Source: Chlorine-treated      Source: Air             Source: Dry-cleaning fluid
        water in hot showers          fresheners,             fumes on clothes
                                                                                             Formaldehyde
        Possible threat: Cancer       mothball crystals       Threat: Nerve disorders,
                                      Threat: Cancer          damage to liver and            Source: Furniture stuffing,
                                                              kidneys, possible cancer       paneling, particleboard,
1,1,1-Trichloroethane                                                                        foam insulation
 Source: Aerosol sprays                                                                      Threat: Irritation of eyes,
 Threat: Dizziness,                                                                          throat, skin, and lungs;
 irregular breathing                                                                         nausea; dizziness
                                                                                             Styrene
Nitrogen oxides                                                                               Source: Carpets,
 Source: Unvented gas stoves                                                                  plastic products
 and kerosene heaters,                                                                        Threat: Kidney and
 woodstoves                                                                                   liver damage
 Threat: Irritated lungs,
 children's colds, headaches                                                                 Benzo- α -pyrene
Particulates                                                                                  Source: Tobacco
                                                                                              smoke, woodstoves
 Source: Pollen, pet                                                                          Threat: Lung cancer
 dander, dust mites,
 cooking smoke                                                                               Radon-222
 particles
                                                                 Tobacco smoke                Source: Radioactive soil
 Threat: Irritated lungs,
                                                                  Source: Cigarettes          and rock surrounding
 asthma attacks, itchy
                                                                  Threat: Lung cancer,        foundation, water supply
 eyes, runny nose, lung
                                                                  respiratory ailments,       Threat: Lung cancer
 disease
                                                                  heart disease
         Asbestos                    Carbon monoxide           Methylene chloride
          Source: Pipe insulation,   Source: Faulty              Source: Paint strippers
          vinyl ceiling and floor    furnaces, unvented gas      and thinners Threat:
          tiles Threat: Lung         stoves and kerosene         Nerve disorders, diabetes
          disease, lung cancer       heaters, woodstoves
                                     Threat: Headaches,
                                     drowsiness, irregular
                                     heartbeat, death                                                   Fig. 18-16, p. 484
► Pesticides,lead tracked into carpet
► Living organisms
   Dust mites, cockroach droppings, mold spores,
    mildew
   Asthma, allergies
► EPA’s   “Fatal Four”
  1. Tobacco smoke     2. Formaldehyde
  3. Radon             4. Very small SPM
► Formaldehyde
   Common preservative in household/bldg materials
   Can lead to cancer
   Problem with Katrina trailers (2008 CDC study)
► “Sick   Building Syndrome”
   20+% ill with flu-like symptoms
           CASE STUDY: Radon
► Decay of U-238 in soil to
  Rn-222
► Natural
► Seeps into buildings
  through foundation
  cracks/openings
► Builds up in basements
► Damages lung tissue 
  cancer
► Remediation method
            Human Health Effects
►   Respiratory System
     Hairs, mucus lining, cilia,
      sneezing, coughing
     Tobacco smoke & air
      pollutants paralyze and
      bypass defenses
     Lung cancer, asthma,
      emphysema, chronic
      bronchitis
     Elderly, infants, pregnant
      women
            Premature Deaths
► WHO:    3M die prematurely each year
   73% due to indoor air pollution
► US   EPA estimate: 150,000-350,000 die
   More suffer- asthma, resp problems etc.
► EPA and American Lung Assoc. estimates
 cost of $150 billion/year in health care and
 lost productivity
Preventing & Reducing Air Pollution
           Laws & Regulations
► Priorto 1970, controls at local & state level
► Air Pollution Control Act, 1955
   Allocated money to help states control pollution
► Clean   Air Act, 1963
   Allowed individual states to set specific
    standards for pollutants
► Air   Quality Control Act, 1967
   Divided country into Air Quality Control Regions
   Defined methods for setting emission standards
                     Clean Air Acts
►   1970 Reauthorization
     Standardized enforcement and standards… federal mandates
      each state must enforce
     EPA establish NAAQS
       ► CO, NOx, SO2, SPM, O3, Pb
       ► “Primary Standard” (human health)
       ► “Secondary Standard” (envi, crop, visibility & property damage)
       ► “Prevention of Significant Deterioration”

►   1990 Reauthorization
     Addressed acid rain, urban smog, toxic air pollutants, ozone
      protection, VOCs
     Marketplace reductions
►   1997 addition … reduced ambient ozone from 0.12 to
    0.08 ppm
                      HAPs
► “Hazardous  Air Pollutants”
► EPA set emission standards for 188 substances
► Mostly chlorinated hydrocarbons, VOCs, toxic
  metals
► Toxic Release Inventory (TRI)
   Annual reporting by 21,500 refineries, power
    plants, mines, chemical co, factories
   Report toxic releases and waste management
    methods for 667 toxins
   Freely available online to the public
     Have Laws & Regulations Been
              Effective?
► YES!
   19802006… overall drop of 49%
     Pb down 97%         O3 down 21%
     CO down 50%         SO2 down 47%
     NOx down 33%
     VOCs down 52%       SPM down 28%
► 2006/2007   Low sulfur diesel fuel
   Mandated by regulation written in 90’s
   Raised fuel costs by 5¢/gallon
   Annual health care cost savings of $150B
       Improving Clean Air Acts
► Focus more on prevention, not cleanup
► Raised fuel efficiency standards (recently done by
  Obama, 35.5 mpg by 2016)
► More  regulation of motorcycles & 2-cycle gas
  engines (lawn mower, snowmobile, etc.)
► Regulate emissions from oceangoing ships in
  American ports
► Regulate airports, not exempt from many regs
► Regulate CO2, ultrafine particles, indoor air
  pollutants
► Stricter limits for urban ozone
► Better enforcement of Clean Air Acts
           Market Reductions
► Emissions    Trading (Cap-&-Trade)
   1990 Clean Air Act
   Allowed 110 most polluting power plants in 21
    states to buy & sell pollution rights for SO2
    ONLY
   Surplus credits could be used for other plants,
    saved for future expansion, sold to other
    utilities, private citizens, or envi groups
   Cap can be lowered every few years
► Is   this good?
   Proponents:
       ►Cheaper   & more efficient than government
   Critics:
       ►Stillpolluting, can buy way out
       ►Creates “hot spots”, moving around pollution
       ►Self-reporting allows cheating

► The   data…
   1990-2006 SO2 down 53%
   <1/10th projected cost by industry
► Being    tried for NOx
SOLUTIONS
         Stationary Source Air Pollution

Prevention                                 Dispersion or
                                           Cleanup
Burn low-sulfur coal
                                           Disperse emissions
                                           above thermal
                                           inversion layer with tall
Remove sulfur from                         smokestacks
coal
                                           Remove pollutants
Convert coal to a                          after combustion
liquid or gaseous
fuel

Shift to less polluting                    Tax each unit of
energy sources                             pollution produced

                                                                 Fig. 18-22, p. 491
 SOLUTIONS
         Motor Vehicle Air Pollution
Prevention                             Cleanup
Use mass transit                       Require
                                       emission
Walk or bike
                                       control devices
Use less polluting
fuels
Improve fuel                           Inspect car
efficiency                             exhaust
                                       systems twice
Get older, polluting
                                       a year
cars off the road
Give large tax write-
offs or rebates for
buying low-polluting,                  Set strict
energy efficient                       emission
vehicles                               standards
                                                         Fig. 18-23, p. 491
            SOLUTIONS
                   Indoor Air Pollution
Prevention                          Cleanup or Dilution
Clean ceiling tiles and line
AC ducts to prevent                 Use adjustable fresh air
release of mineral fibers           vents for work spaces

Ban smoking or limit it to
well-ventilated areas               Increase intake of outside
                                    air

Set stricter formaldehyde           Change air more
emissions standards for             frequently
carpet, furniture, and
building materials                  Circulate a building’s air
                                    through rooftop
Prevent radon                       greenhouses
infiltration
Use office machines in              Use efficient venting
well-ventilated areas               systems for wood-
                                    burning stoves
Use less polluting
substitutes for harmful             Use exhaust hoods for
cleaning agents, paints,            stoves and appliances
and other products                  burning natural gas
                                                                 Fig. 18-24, p. 492

				
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