GEOG 3000 Resource Management Smog, Acid Deposition

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GEOG 3000 Resource ManagementSmog, Acid
Deposition Global Warming.

• M.D. Lee CSU Hayward Winter 2004

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SMOG and Acid Deposition

• The loss of air quality creates many
  environmental externalities that can affect other
  resource areas - land, food production, etc.
• SMOG and acid deposition are closely linked and
  have ranges of influence from tens to thousands
  of kilometers.
• SMOG is an urban problem, but spreads out into
  rural areas as winds redistribute pollutants,
  particularly the byproducts of burning fossil
  fuels.

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SMOG

• Originally derived from the words smoke and fog,
  it was associated with coal and cold, damp, foggy
  locations.
• Sulfur dioxides from coal would create dense fogs
  with a very low pH and trigger acid-irritated
  bronchitis and pneumonia.
• Today, we keep the word SMOG but the source is
  now gasoline and the main culprits nitrogen
  oxides and unburned hydrocarbons.
• SMOG today is photochemical in nature, associated
  with hot, sunny, dry locations.
• Some regions where heavy coal use occurs, as in
  China, still suffer the London type smog.

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Nature of SMOG

• The modern internal combustion engine is still
  relatively inefficient - it generates
  temperatures high enough to fuse nitrogen and
  oxygen.
• It is not stoichometric, i.e it leaves an
  unburned mix of CO and non-combusted volatile
  reactive hydrocarbons (VOCs).
• In urban areas, other raw hydrocarbons come from
  paints, leaky gas pumps, dry cleaners, BBQs,
  trees, etc.
• With the energy from sunlight (hv), photolysis
  occurs to create smog.
• VOCs OH NO ( hv O2)? HCs NO2 O3

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SMOG Production
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Spare the Air

• The primary pollutants become more harmful
  secondary pollutants in sunshine e.g.NO2 HNO3,
  ground level ozone O3, PANs (peroxyacl nitrates).
• These are the principal components of SMOG a
  dirty brown haze visible on sunny, dry
  afternoons.
• Ozone (O3) is good for us on the edge of the
  atmosphere, filtering out UV radiation, but is
  very dangerous in the air we breath and very
  damaging to plants.
• CA air quality authorities (e.g. BAAQMD) issue
  Spare the Air smog alerts to commuters.

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Smog Health Effects

• Ground level ozone (O3) damages and ages cells,
  including human lung and skin cells and plant
  tissues.
• Ground level ozone also irritates the eyes and
  lungs and causes headaches.
• NO2 HNO3 promote surface diseases on the lungs,
  cause bronchitis, asthma, respiratory failure and
  heart attacks.
• PANs cause tearing and conjunctivitis (pink eye).

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Ecological Effects

• Smog can seriously damage the leaf surfaces of
  vegetation, preventing effective photosynthesis
  (e.g. east of LA basin, German Black Forest,
  hinterlands of Beijing).
• Impact of smog-causing NOxs on the formation of
  acid deposition (acid rain).
• NOx oxygen water gives us Nitric Acid or HNO3
  in our rain, snow, mist, dust.
• Similarly, from coal and diesel smoke, the SO2
  oxygen water gives us Sulfuric Acid or H2S04

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Acid Deposition
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Acid deposition

• Acid deposition, obeying the what goes up must
  come down principal, is the return to earth of
  acidic particles or droplets released from
  pollution sources.
• Rain is always a little acid around pH 5.0-5.7,
  but acid rain can be as acid as vinegar and lemon
  juice around pH 2.3-3.0.
• Back East in the mid-West the problem is
  sulfur/coal whereas in California it is nitrogen
  oxides/gasoline.

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Acid Impacts

• Acid deposition kills aquatic life in rivers and
  lakes by a variety of mechanisms.
• Changing acidity (from higher to lower pH) in
  lakes and streams changes ecological niches.
• Higher acidity causes physical damage to
  organisms such as skin lesions and mucus-clogged
  fish gills.
• Higher acidity can make otherwise insoluble and
  thus non-bioavailable toxic chemicals become
  soluble in water so that they become acutely
  toxic or begin to bioaccumulate by entering
  tissues.
• Higher acidity can prevent nutrient cycling
  leading to reduced plant growth and oxygenation.

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More Acid Impacts

• Acid deposition has a range of impacts on
  vegetation as well as aquatic organisms.
• Acid deposition stunts or kills crops and trees
  by physically damaging leaves and preventing
  photosynthesis.
• Acidity increases in soil water can make toxic
  aluminum in the soil soluble, harming root
  development.
• Increased acidity of soil water intensifies the
  leaching of nutrients from the soil and slows
  organic decomposition and nutrient release.
• Acid deposition impacts are thought to cause an
  estimated 5billion in US farm losses annually.

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SMOG Relief

• Resource solutions for SMOG are of varying types,
  encompassing technology and behavioral change.
• Fuel related changes - adding oxygenates to
  enhance combustibility.
• Technology changes - pump recovery systems, lower
  temperature engines, catalytic converters,
  zero/low emission engines (electric, natural gas,
  etc.), higher MPGs.
• Behavioral changes use of mass transit,
  alternative transportation, increased taxes
  (fuel, parking, tolls), spare-the-air emergency
  responses, etc.
• Others - SMOG laws and removing gross polluters,
  etc.

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Acid Relief

• Reducing smog forming chemicals is a major help
  in preventing acid deposition.
• Reduce the amount of NOx produced especially
  through the use of more efficient transport,
  using less gas per person per year, and using
  cleaner burning engines.
• On average, each car in America will put out
  about 41 lbs of NOx each year.
• Reduce the amount of SO2 produced by using less
  coal, cutting down electrical energy use per
  person per year, using only the cleanest coal,
  and using sulfur scrubbers on smoke stacks.

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Global Warming

• Short wave radiation enters from the sun.
• What is not reflected out causes chemical
  reactions in the atmosphere, generating heat, or
  is absorbed by the earths surface and converted
  to longer-wave thermal radiation which radiates
  back into space.
• Changes to the earths albedo (reflectiveness)
  and atmospheric composition alters how much
  energy enters and is retained and thus the
  average temperature of the atmosphere.
• Without this self-regulating mechanism of heat
  conversion and transference, the earth would
  either be too cold or too hot.
• The main key heat absorbing, greenhouse gases
  today are carbon dioxide CO2, Methane CH4,
  Nitrous oxide N2O, CFCs, and Ozone O3.

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The Global Heat Balance
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What we know about GW

• CO2 content of the air has increased from 280 to
  360 PPM since the industrial revolution.
• Average world temperatures have risen by around
  0.5 centigrade in the last 100 years.
• The levels of CFCs, nitrous oxide and methane
  have also increased in the upper atmosphere.
• The ozone layer above the poles continues to
  thin.
• The worlds forested area has shrunk by more than
  50 in 100 years.
• The last 20 years has been dominated by a series
  of record climatic highs.
• Sea levels have risen 1 foot in the last 100
  years and alpine glaciers are shrinking/retreating
  rapidly.

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Anthropogenic greenhouse gases in the atmosphere.
(Source Carbon Dioxide Information Analysis
Center, Oak Ridge National Laboratory.)
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Thinning of the Protective ozone layer. An
exacerbating factor since more energy comes in to
be converted to thermal energy.
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Clean Air and the Ozone Layer

• Following the identification of CFCs
  (Chlorofluorocarbons) as destroyers of the
  earths ozone layer (Rowland and Molina) in the
  1970s, the US banned their use in aerosols in
  1978.
• The 1990 CAA followed the UN Montreal Protocol
  and banned all production of CFCs by 1996, halons
  by 1994, carbon tetrachloride by 1996, and methyl
  chloroform by 1996. Less harmful substitutes are
  available!
• Car air conditioners have been the biggest single
  source of ozone destroying chemicals and CFC use
  was stopped in 1993 and auto services were
  required to recycle and prevent the release of
  CFCs from older cars.
• Ozone depletion is likely to persist, however,
  for 100 or so years!

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What we dont know about GW

• If we are just seeing the effects of short-term
  changes in the suns activity (sunspot cycles)?
• How much of the CO2 will be reabsorbed by the
  oceans and by increased plant growth?
• How the polar ice sheets will react - whether
  they will build mass due to more snow in the
  center or lose mass due to melting at the
  margins?
• How much new forest will be added and old forest
  lost?
• How much extra methane will be produced from new
  wetlands if sea levels rise and flooding occurs?
• Whether cloud masses will respond to be our
  global thermostat with more low level clouds
  reflecting a greater proportion of incoming
  energy back out to space?

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GW What the experts think

• Many different global climate computer simulation
  models have been developed, all with slightly
  different assumptions
• However, while there are extreme views that
  suggest enormous sea rises on the one hand, or
  virtually no, even overall beneficial changes on
  the other, the majority of scientists predict
  significant negative impacts.
• The Intergovernmental Panel on Climate Change
  (IPCC), made up of respected US and foreign
  scientists including many Nobel laureates, gave
  their majority opinion as early as 1995 that GW
  is a certainty and US government reports in 2000
  also confirmed this.
• Some US Politicians still persist in a) denying
  GW is real b) doubting predictions c) suggesting
  that developing nations like India and China
  should agree to do more before we do.

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Atmospheric carbon dioxide concentrations. The
concentration of CO2 in the atmosphere fluctuates
between winter and summer because of seasonal
variation in photosynthesis. The average
concentration is increasing owing to human
activities in particular, burning fossil fuels
and deforestation. (All measurements made at
Mauna Loa Observatory, Hawaii, by Dave Keeling
and Tim Whorf, Scripps Institute of Oceanography.)
Annual mean global surface atmospheric
temperatures. The baseline, or zero point, is the
18801999 long-term average temperature. The
warming trend since 1970 is conspicuous. (Source
National Climatic Data Center, NOAA.)
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Changes in temperature over the United States.
Assuming a 1-per-year increase in greenhouse gas
emissions, the U.S. assessment models forecast a
temperature increase ranging from 5 to 9ºF by the
end of the 21st century. (Source U.S. Global
Change Research Program, U.S. National
Assessment, 2000.)
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GW - Some Resource Impacts

• Land will be lost due to sea level increases and
  new erosional effects on coastal margins.
• Frequency and intensity of water resource
  problems will increase - longer, drier droughts
  and more extreme floods, saline intrusion to
  coastal aquifers, tropical diseases will
  flourish.
• Forestry productivity will decline in temperate
  regions due to the stress of warming conditions
  and biodiversity will be reduced because of
  too-rapid changes.
• Agricultural productivity may rise/fall in
  different localities due to climatic changes and
  salinization and waterlogging of soils.
• Climatic hazards like hurricanes and tornadoes
  will damage resource production systems and
  infrastructure.

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GW Solutions

• Reduce worldwide fossil-fuel usequickly!!!!
• Use energy more efficiently - could reduce
  emissions by 10-40 at little or no net cost
  (Emory Lovins and his negawatts).
• Shift from fossil fuels to renewable sources of
  energy, preferably perpetual ones solar, wind
  can also use biomass gasohol, gasoline plants,
  sustainable wood production, etc.
• Switch to natural gas in the short to medium run
  as the preferred fossil fuel (cleanest burning
  and releases the least CO2 per unit of energy
  produced).
• Export the most efficient energy-using
  technologies to the less developed nations,
  especially cleaner-burning coal-powered thermal
  plants for electricity production to China and
  India.

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Stepping up to the plate!
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Other broader GW solutions

• Promote sustainable agriculture in developing
  countries to reduce the rates of deforestation
  and slash-and-burn.
• Promote reforestation efforts globally,
  particularly in the tropics.
• Point pollution controls - reduce industrial and
  automotive emissions from smokestacks and shut
  down old and inefficient facilities that cant be
  retrofitted.
• Reduce global use of industrial greenhouse gases
  and ozone depleting chemicals.
• Reduce population growth to keep the number of
  energy consumers down.

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Forests and Global Warming

• Forest biomass and the soils below hold 40 of
  the terrestrial carbon, and the current global
  net forest loss is a key part of the net addition
  to atmospheric CO2.
• Forests cover some 25 of the planet but have
  been reduced by up to 50 over pre-agricultural
  times.
• Less than 40 of the worlds forests are
  undisturbed, i.e. have not been subject to
  logging of some kind.
• Tropical deforestation is said to be around
  130,000 km2 per year (WRI 2001).
• Forest cover in the industrialized countries is
  stabilizing but is being depleted rapidly in the
  tropics.