Transcript Document

AIR POLLUTION
COMPOSITON OF AIR
•
•
•
•
78% Nitrogen (N2)
21% Oxygen (O2)
0.9% Argon
0.035% (CO2)
POLLUTION
• Anything that
negatively
affects the
health,
survival, or
activities of
humans or
other living
organisms.
EFFECTS OF AIR
POLLUTION
• Human Health
– ACUTE: short duration
exposure and/or immediate
effects
Examples:
irritation of eyes, nose and
throat
upper respiratory infections
(bronchitis, pneumonia)
headaches
nausea
allergic reactions, etc.
EFFECTS OF AIR
POLLUTION
• Human Health
– CHRONIC: long
duration exposure
and/or long term effects
Examples:
lung cancer
heart disease
damage to brain,
nerves, liver,
kidneys,
etc.
EFFECTS
OF AIR
POLLUTION
• Aesthetic
EFFECTS
OF AIR
POLLUTION
• Damage to
organisms
Air pollution damage to
spruce and to red alder trees.
Air pollution damage to white pine.
MN. Dept. Nat. Res. Archive
Damage to pine due to S02
MN. Dept. Nat. Res. Archive
EFFECTS
OF AIR
POLLUTION
• Damage to
ecosystems
Spruce forest.
Decline of forests due to air pollution.
EFFECTS
OF AIR
POLLUTION
• Damage to
property
Effects of dry deposition of
sulfur dioxide, which
causes the formation of
gypsum. Gypsum traps
particulate matter to form
heavy, black incrustation.
FACTORS INFLUENCING
EFFECTS
• Chemical Nature
– How active and harmful
• Concentration
– See Temperature Inversions
• Persistence
– How long pollutant stays around
TEMPERATURE
INVERSION
• Normally air temp decreases with increasing
altitude.
– Ground heats up and heats air above it
which rises, expands, and cools.
– This rising air carries pollutants up and
away from where humans breathe and dilute
the pollutants in more air space.
TEMPERATURE
INVERSION
• Temperature Inversion: occurs at ground level when
cool air is created under or slips under relatively
warmer air just above it.
TEMPERATURE
INVERSION
• Temperature Inversion: occurs at ground level when
cool air is created under or slips under relatively
warmer air just above it.
TEMPERATURE
INVERSION
• Temperature Inversion: occurs at ground level when
cool air is created under or slips under relatively
warmer air just above it.
TEMPERATURE
INVERSION
• Temperature Inversions break when
– Sun comes out and heats ground which heats
air above ground to warmer than layer
above it.
– During cloudy weather, sun may not be
strong enough to break up inversion for
several hours or days.
TEMPERATURE
INVERSION
• Temperature Inversions are bad because
– Air pollution concentrates in this layer
that we breathe.
• In 1963, 300 people in NY City died
due to temp inversion.
TEMPERATURE
INVERSION
• Temperature Inversions
– Occur almost every night
– Occur more dramatically in cities near
mountains
• This is why we have smokestacks
SOURCES OF AIR
POLLUTION
• Natural sources include:
– Volcanoes, fires, dust
storms…
Greece 2007
SOURCES OF AIR
POLLUTION
• Human (Anthropogenic)
– Stationary vs. Mobile
• Stationary: e.g., power
plants
• Mobile: e.g.,
transportation
SOURCES OF AIR
POLLUTION
• Primary vs. Secondary
• Primary pollutants: enter air directly as
pollutants – direct products of combustion
and evaporation.
• Secondary pollutants: primary pollutants
that undergo further reactions in
atmosphere to produce additional
undesirable compounds.
PRIMARY VS SECONDARY
TYPES OF AIR
POLLUTANTS
• Criteria Pollutants
– Clean Air Act
mandates NAAQS-national ambient air
quality standards (max
concentrations that can
be in the air).
– SPLONC = SO2,
Particulate Matter,
Lead, O3, NO2, CO
NAAQS
• these are primary
standards intended to
protect human health
SULFUR DIOXIDE: SO2
• Sources: mostly stationary fuel combustion
(esp. coal power plants)
• Main Effects:
– Acid Deposition
– Corrosive
• Damages lungs
• Damages structures
• Damages environment
PARTICULATE MATTER
• Examples: dust, soot, lead, arsenic
• Sources: industry (38%) and stationary
(25%) and mobile (21%) fuel combustion
• Main Effects: depends on pollutant
– Usually decreases lung function
LEAD
• Sources: paints and smelting plants
• Main Effects:
– Affects brain and nervous system
OZONE: O3
• Sources: secondary pollutant from
nitrogen dioxide, hydrocarbons, sunlight
– Mostly transportation; also stationary
fuel combustion
• Main Effects:
– Damages lungs; irritates eyes
– Damages plants
– Damages structures
NITROGEN DIOXIDE: NO2
• Sources: secondary pollutant from nitrogen
oxide
– Mostly fuel combustion (stationary and
transportation)
• Main Effects:
– Acid Deposition
– Forms ozone
– Damages lungs
– Produces brown haze in air
CARBON MONOXIDE: CO
• Sources: mostly transportation
• Main Effects:
– Reduces blood’s capacity to carry
oxygen (headaches and worse)
– Forms ozone
TYPES OF AIR
POLLUTANTS
• Noncriteria Pollutants
– Clean Air Act
mandates emission
standards (how
much can come out
of the smokestack)
– Examples: arsenic,
asbestos, mercury,
radioactive
isotopes.
PRINCIPAL
POLLUTANTS
PRINCIPAL POLLUTANTS
PANs = peroxyacetyl nitrates, highly reactive and damaging compounds.
THERE ARE TWO KINDS
OF SMOG
• Industrial smog (gray smog) occurs where
coal is burned and atmosphere is humid.
• Photochemical smog (brown smog) occurs
where sunlight acts on vehicle pollutants.
TRENDS IN AIR POLLUTION
WAYS TO REDUCE AIR POLLUTION
• DRIVE LESS  carpool, walk or ride a bike,
shop by phone or mail, ride public transit,
telecommute.
• DRIVE SMART  obey the speed limit,
combine all errands in one trip, use cruise
control, keep car tuned, don’t top off at the pump,
replace car’s air filter, keep tires properly
inflated, buy clean cars.
• BUY AIR-FRIENDLY PRODUCTS  buy
products that are water-based or are low in
VOCs, buy water-based paints, paint with a brush
instead of a sprayer, use a push or electric lawn
mower, use propane or gas barbecue.
WAYS TO REDUCE AIR POLLUTION
•SAVE ENERGY  turn off lights when you
leave a room, use fluorescent lighting, use a
programmable thermostat, insulate your
home, use a fan instead of an air-conditioner,
install low-flow shower heads.
• WASTE NOT  choose recycled products,
choose products with recycled packaging,
print or xerox on both sides of the paper, reuse
paper bags, recycle papers, plastics and
metals.
• DON’T CREATE DUST  don’t use
fireplace on days with unhealthy air, use rake
instead of leaf blower, drive slowly on dirt
roads.