Download Indoor air pollution

Scott Brennan • Jay Withgott
8
The atmosphere, air
pollution, and global
climate change
PowerPoint® Lecture prepared by Jay Withgott
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
This lecture will help you understand:
• Composition, structure, and
function of the atmosphere
• Outdoor air pollution
• Indoor air pollution
• Stratospheric ozone
depletion
• Acid precipitation
• Human influences on
atmosphere and climate
• Effects of climate change
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Central Case: Rising temperatures and seas
may take the Maldives
• 80% of this island nation’s land is <1 m above water.
• Globally warming temperatures are causing sea levels to
rise worldwide, endangering many island nations.
• They beg the U.S. and others to reduce fossil fuel use.
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Our atmosphere
Earth’s atmosphere = the layer
of gases that surround the planet
Very thin layer, relative to size
of planet
Atmosphere:
• Absorbs solar
radiation
• Burns up meteors
• Transports and
recycles water, and
other chemicals
• Moderates climate
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Atmosphere composition
78% nitrogen
21% oxygen
1% argon
traces of other gases and variable small amounts of:
water vapor
carbon dioxide
methane
pollutants
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Atmospheric layers
Atmosphere consists of several layers:
Troposphere = Bottom layer, at Earth’s surface. 11 km high.
Temperature decreases with altitude.
Stratosphere = Next layer up (11–50 km). Temperature
increases with altitude. Contains “ozone layer.”
Mesosphere = Third layer up (50–90 km). Temperature
decreases with altitude.
Thermosphere = Top layer (90–500 km). Very thin air;
mostly lightweight elements. Very hot. Ionic radiation.
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Atmospheric layers
Temperature and other
characteristics vary with
altitude.
Ozone layer
Tropopause
marks boundary
between
troposphere and
stratosphere.
Layers don’t mix.
Figure 11.3
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Ozone layer
Not really a layer, but a region
of higher-than-normal ozone
concentrations (which are still
very low)
~17–30 km altitude
Ozone = O3—molecule of 3
oxygen atoms
Absorbs ultraviolet (UV)
radiation from sun, protecting
organisms on surface from
radiation damage
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Radiation, atmosphere, and temperature
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Figure 12.1
Weather and climate
Weather = local physical properties of the troposphere,
including temperature, pressure, humidity, cloudiness, wind
Climate = pattern of atmospheric conditions across large
geographic regions over long periods of time (seasons,
years, millennia)
“Climate is what we expect; weather is what we get.” –Mark Twain
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Temperature, or thermal, inversion
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Global climate patterns
… result from differential heating of Earth’s
surface.
And from gigantic convection currents called
Hadley cells, Ferrel cells, and polar cells
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Global convection currents
Hadley cells: air rises
at equator, falls at 30º
latitude.
Ferrel cells: air falls
at 30º, rises at 60º.
Polar cells: air rises
at 60º, falls at 90º.
Figure 11.10a
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Global wind patterns
These 3 types of cells also
influence wind patterns
near the ground.
The Coriolis effect
(planet’s rotation causes
land at the equator to spin
more quickly than
temperate land) causes
north-south winds to
appear to be deflected, and
to curve.
Figure 11.10b
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Outdoor air pollution
Air pollution = material added to the atmosphere that can
affect climate and harm organisms, including humans
Air pollution can come from human-made chemicals and
causes, but the majority is from natural sources.
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Natural sources of air pollution
dust storms
volcanoes
fires
Figure 11.11
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Artificial sources of air pollution
Human-caused air pollution includes:
Point sources = specific spots where large
amounts of pollution are discharged
(factory smokestacks)
Non-point sources = diffuse, often made up of
many small sources
(charcoal fires from thousands of homes)
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Artificial sources of air pollution
Human-caused air pollution includes:
Primary pollutants = emitted into troposphere in a directly
harmful form
(soot, carbon monoxide)
Secondary pollutants = produced via reaction of
substances added to the atmosphere with
chemicals already present in the atmosphere
(ozone in troposphere)
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Six “criteria pollutants”
The EPA closely tracks 6 major types of pollutants:
• Carbon monoxide (CO)
• Sulfur dioxide (SO2)
• Nitrogen dioxide (NO2)
• Tropospheric ozone (O3)
• Lead (Pb)
• Particulate matter
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Six “criteria pollutants”
Emissions of all of these, especially lead and carbon
monoxide, have substantially declined since 1970.
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Figure 11.12
CO / SO2 / NO2
Carbon monoxide (CO) = colorless, odorless gas. From
vehicle exhaust and other sources. Dangerous; prevents
oxygen uptake.
Sulfur dioxide (SO2) = colorless gas. From coal burning
for electricity and industry. Contributes to acid
precipitation.
Nitrogen dioxide (NO2) = foul-smelling red gas. From
vehicle exhaust, industry, electricity. Contributes to smog
and acid precipitation.
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O3 / Pb / particulate matter
Tropospheric ozone (O3) = colorless gas. Secondary
pollutant from sunlight, heat, nitrogen oxides (NOx), and Ccontaining chemicals. Contributes to smog; harmful to
living tissues.
Lead (Pb) = metal in atmosphere as particulate. From
gasoline additive, phased out in 1980s. Diverse health
impacts, all bad.
Particulate matter = any solid (or liquid) particles small
enough to be carried aloft in air. Dust, soot, sulfates,
nitrates. Causes respiratory damage.
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Success against lead
A major source of lead, an additive in gasoline, was banned
when its health effects became obvious.
This came about through cooperative action among
government, industry, scientists, citizens.
Lead emissions in the U.S. dropped 93% between 1982
and 2001.
Huge victory for public health
Example of what can be done
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Volatile organic compounds
“VOCs” are regulated by many governments.
Large group of potentially harmful carboncontaining chemicals used in industrial processes
Hydrocarbons are one example.
About half are human-made, half natural.
VOCs contribute to smog, produce secondary pollutants.
Most of the 188 pollutants identified by 1970 Clean Air Act are VOCs.
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Industrial smog
Smog from industrial pollution, fossil-fuel combustion
The kind that blanketed London in 1952
“Gray air smog”
Contains soot, sulfur, CO, CO2…
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Industrial smog
The U.S. had its own “killer smog” from industrial
pollution. Shown is Donora, Pennsylvania, in 1948, at midday. Subsequent demand for legislation against pollution
made U.S. air much cleaner.
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Figure 11.14b
Industrial smog
Chemistry of industrial
smog:
• Burning sulfur-rich
oil or coal creates
SO2, SO3, sulfuric
acid, ammonium
sulfate.
• Carbon leads to CO2
and CO.
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Figure 11.14a
Photochemical smog
Smog from reaction of sunlight with pollutants
The kind that blankets so many American cities today
“Brown air smog”
Contains tropospheric ozone, NO2, VOCs, 100 more…
Hot sunny days in urban areas create perfect conditions.
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Photochemical smog
Mexico City and many of the world’s cities suffer from the
brownish haze of photochemical smog.
Inversion layers and mountains can trap smog over certain
cities.
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Figure 11.15a
Photochemical smog
Chemistry of
photochemical
smog:
Nitric oxide starts
a chain reaction.
Reaction with
sunlight, water
vapor,
hydrocarbons,
results in over 100
secondary
pollutants.
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Figure 11.15b
Stratospheric ozone depletion
Ozone in troposphere = harmful pollutant
Ozone in stratosphere = beneficial layer protecting us
from UV radiation
“Ozone layer”— ~ 12 parts per million in lower
stratosphere—is enough to absorb UV and protect us.
But in the 1960s scientists noticed ozone concentrations
were dropping.
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Stratospheric ozone depletion
In 1974, Sherwood Rowland and Mario Molina pegged the
blame on chlorofluorocarbons (CFCs).
They won the Nobel Prize for this scientific detective work.
CFCs = human-made molecules in which hydrogens of
hydrocarbons are replaced by chlorine and fluorine atoms
Mass-produced by industry, in refrigerants and consumer
products like aerosol sprays
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Stratospheric ozone depletion
In 1985, the “ozone hole” was detected over Antarctica.
Ozone levels had declined 40–60% over the previous
decade.
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Figure 11.17a
Stratospheric ozone depletion
Scientists worried about the effects of extra cancer-causing
UV on people, organisms, ecosystems.
The ozone hole
(blue) reached its
greatest extent in
September 2000
(satellite imagery).
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Figure 11.17b
Stratospheric ozone depletion
In 1987, over 180 nations signed the Montreal Protocol,
which restricted CFC production globally.
Follow-up agreements strengthened the pact.
Today CFC levels are down, and stratospheric ozone is
starting to recover.
The Montreal Protocol is one of the biggest environmental
success stories of our time.
We have apparently avoided a major environmental
problem.
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Stratospheric ozone depletion
Reasons for success of the Montreal Protocol:
• Government and industry cooperated on finding
solutions (cheap replacement technologies for CFCs),
so battles typical to environmental debates were
minimized.
• Protocol was implemented with “adaptive
management”—ability to fine-tune actions as time
goes on, in response to new data or conditions.
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Acid precipitation
Acid rain, acid fog, acid snow
Caused by reaction of pollutants like SO2 and NO with
water, oxygen, and oxidants to form acids that fall to
surface in precipitation:
sulfuric acid (H2SO4)
nitric acid (HNO3)
Like ozone depletion, this is another transboundary
pollution issue, i.e., it crosses political boundaries.
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Acid precipitation
Acid precipitation is created by reactions in the atmosphere,
and can fall many miles from where pollution originated.
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Figure 11.18
Acid precipitation
Acidity varies geographically. (Orange = more acidic)
Industrialized areas and regions downwind of them suffer
most.
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Figure 11.20
Acid precipitation
Acid precipitation has killed these conifer trees in the
mountains of North Carolina.
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From The Science behind the Stories
Acid precipitation
This can be seen in data from New Hampshire’s Hubbard
Brook Experimental Forest, where acid rain was first
studied. pH has increased (rain has become less acidic)
since 1970, but is still much more acidic than normal rain.
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From The Science behind the Stories
Indoor air pollution
Indoor air spaces generally have MORE pollution than
outdoor spaces.
U.S. citizens spend 90% of time indoors.
Countless consumer products and synthetic chemicals kept
indoors are used in our daily lives.
UN estimate for world:
2.2 million deaths/year from indoor air pollution
0.5 million deaths/year from outdoor air pollution
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Indoor air pollution
In developing
nations, indoor
cooking fires
are common,
and a major
health risk.
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Figure 11.21
Indoor air pollution
Burning fuel wood inside homes for cooking is a major
source of indoor pollution in developing countries.
In developed nations, the 2 biggest threats seem to be:
cigarette smoke: lung cancer risk for smokers and
those inhaling secondhand smoke
radon: naturally occurring colorless, odorless gas.
Radioactive, seeps up from ground and
collects in buildings. Lung cancer risk.
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Other indoor air pollution risks in the home
Asbestos: in insulation, ceilings, walls...
Lung disease, cancer
Organisms: mold, mildew, dander, pollen, mites... Allergic
reaction
Carbon monoxide: poor ventilation, leaky furnace...
CO poisoning
Formaldehyde: paneling, furniture, carpets…
irritation, cancer
Lead: lead-based paint, drinking water… lead poisoning
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Other indoor air pollution risks in the home
Pesticides: numerous ingredients…
nervous system damage
Soot and particulates: fireplaces, woodstove…
respiratory problems
VOCs: carpets, cleansers, paints, detergents…
various effects
Endocrine disruptors: fire retardants, pesticides…
hormone problems
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Reducing indoor air pollution
Buy and use low-toxicity products
Provide good ventilation
Limit exposure to plastics, treated wood, pesticides,
cleansing fluids (put in garage, not home)
Test home for radon
Test drinking water for lead from pipes
In developing world, provide ventilation, install cleanburning stoves, shift to gas
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Climate and climate change
Climate = a region’s long-term pattern of atmospheric
conditions, including temperature, precipitation, and other
variables
Global climate change = changes in climate on a
worldwide scale
Climate changes naturally, and always has, but the recent
rapid warming of the planet and its change in atmospheric
composition are widely thought due to human activities.
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Radiation, atmosphere, and temperature
Earth’s temperature depends on how much of the sun’s
radiation enters the atmosphere and how much escapes back
into space.
Incoming solar radiation is:
absorbed at the surface, or
reflected by the atmosphere, or
reflected by the surface into space.
Infrared radiation emanating from Earth’s heated surface is:
emitted into space, or
absorbed by gases and kept in the atmosphere.
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Radiation, atmosphere, and temperature
Atmospheric gases that absorb the emanating radiation are
greenhouse gases.
By absorbing and re-emitting this radiation, they warm
Earth’s atmosphere and surface, like a greenhouse.
This popularly called the greenhouse effect.
Rising concentrations of greenhouse gases in recent decades
have resulted in global warming, an increase in Earth’s
average surface temperature.
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Carbon dioxide increase
Due to:
Burning of fossil fuels: We remove carbon-rich fuels
from the ground where they have been stored for millions of
years, and combust them in an instant, sending CO2 into the
atmosphere.
Deforestation: Cutting down trees, removing
vegetation from the land, decreases the sink for carbon.
Some of the C in plants becomes CO2 sent into the
atmosphere.
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Studying climate change: Direct sampling
Scientists have recorded
carbon dioxide levels in
the atmosphere directly
since 1958, at a station in
Hawaii.
The data show a steady
upward climb from 315
to 373 ppm.
(The up and down zigzags
are from regular wintersummer fluctuations.)
Figure 12.6
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Increase of other greenhouse gases
Halocarbon gases (which include CFCs) are
powerful greenhouse gases.
But their effects are slowing due to the Montreal
Protocol.
Water vapor is the most abundant greenhouse gas.
Its future changes, if any, remain uncertain.
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Aerosols and cooling
Aerosols (microscopic particles and droplets) in the
atmosphere can:
warm the climate (soot), or
cool the climate (sulfates).
Sulfate-rich volcanic eruptions can cool Earth temporarily.
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Milankovitch cycles
These 3 types of cycles also affect climate in the long term.
Variation of
Earth’s tilt
Variation of
Earth’s orbit
Wobble of
Earth’s axis
Figure 12.3
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El Niño and La Niña
The best-known interactions between oceans and climate
are El Niño and La Niña events.
In normal
conditions, winds
push warm waters
(red) to the western
Pacific Ocean.
This allows cold
water to well up from
the deep in the
eastern Pacific.
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From The Science behind the Stories
El Niño and La Niña
Normal
conditions
In an El Niño event, winds
weaken, warm water sloshes
to the east, and prevents the
cold upwelling.
La Niña is the opposite:
Cold water spreads west.
From The Science behind the Stories
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El Niño and La Niña
El Niño and La Niña events influence rainfall and
temperature globally, especially on each side of the Pacific.
They cause droughts, floods, etc.
They disrupt fisheries (e.g., South American
fisheries dependent on cold water upwelling).
Key question: Is global climate change making these
events more frequent???
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Studying climate change
How do scientists know all these things about what climate
was like in the past, before we were here?
A number of methods have been developed…
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Studying climate change: Ice cores
Ice caps and glaciers
accumulated over thousands
or millions of years.
They contain bubbles of gas
preserved from the time when
each layer formed.
Scientists drill cores and
analyze the gas bubbles in
each layer to see what the
atmosphere was like at that
time.
Figure 12.5
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Studying climate change: Pollen analysis
Scientists also drill cores
into the sediments of
ancient lake beds.
By identifying types of
pollen grains in each
layer, they can tell what
types of plants were
growing there at the
time.
From The Science behind the Stories
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Studying climate change: Modeling
To predict what will happen to climate in the future,
scientists use climate models:
Computer simulations that use known behavior of
past climate to analyze how climate should behave as
variables are changed.
Coupled general circulation models (CGCMs) are models
that combine, or couple, the effects of both atmosphere and
ocean.
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Studying climate change: Modeling
Scientists test their models by entering real data from the
past and seeing how well their model would have predicted
past trends.
They generally find: Models that incorporate only natural
factors or only anthropogenic (human-caused) factors
predict poorly.
But models including both natural and anthropogenic
factors predict very well.
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Studying climate change: Modeling
What does this mean?
Both natural factors and human-caused factors are
influencing climate.
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Climate change and the IPCC report
In 2001, the world’s climate scientists combined to produce
the single most comprehensive and authoritative research
summary on climate change:
The Third Assessment Report
of the
Intergovernmental Panel on Climate Change (IPCC)
The IPCC report summarized all scientific data on climate
change, future predictions, and possible impacts.
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Climate change and the IPCC report
First, the IPCC report established that global temperature is
rising.
Direct measurements from thermometers since 1860
demonstrate this.
Figure 12.9a
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Climate change and the IPCC report
Proxy indicators of temperature (from pollen, ice cores,
etc.) were reviewed to establish ancient temperatures.
These data (BLUE) overlapped with the direct temperature
measurements (RED). (Gray shows statistical uncertainty.)
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Figure 12.9b
The IPCC report
Some key findings on temperature:
• Average temperature rose 0.6°C (1.0°F) during the
20th century
• 1990s = warmest decade in past 1,000 years
• Northern hemisphere increase in 1900s = most in
1,000 years
• Droughts increased in frequency and severity
• Precipitation increased in north, but varied elsewhere
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The IPCC report
The IPCC also reported findings on physical changes:
• Average sea level increased 10–20 centimeters (4–8
inches) during 20th century
• 2 weeks less ice cover on northern lakes and rivers
• Arctic sea ice thinned 10–40% in recent decades
• Mountain glaciers melted back worldwide
• Snow cover decreased 10% since satellite
observations began
• Growing season lengthened 1–4 days each decade
over the past 40 years
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The IPCC report
Biological changes were also found by the IPCC:
• Geographic ranges of many species have shifted
toward the poles and up in elevation.
• In spring, plants are flowering earlier, birds migrating
earlier, animals breeding earlier, and insects emerging
earlier.
• Coral reefs are “bleaching” more frequently.
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The IPCC report
Lastly, the IPCC summarized economic impacts of climate
change:
• Economic losses due to weather and storms rose 10fold over the past 40 years, partly due to climate
change.
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The IPCC report: Causes of climate change
The IPCC report reflected the predominant view of climate
scientists:
Human activities (especially fossil fuel use leading to
rising greenhouse gas levels) are the main cause of
climate change.
However, the ways anthropogenic factors and natural
factors interact is complex and not fully understood, so
predicting the future is uncertain.
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Climate change predictions: Impacts
The IPCC and other groups have predicted future impacts
of climate change. Predictions for the U.S. include:
• Temperature will rise 3–5°C (5–9°F).
• Droughts, floods, snowpack will decline, and water
shortages will create diverse problems.
• Temperature extremes will cause health problems;
tropical diseases will move north into the U.S.
• Sea level rise will flood coastal wetlands, real estate.
• Ecosystems will be altered; some will disappear.
• Agriculture and forestry may have mixed results.
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Sea level rise
Just as sea level rise
could devastate the
Maldives…
… it could also inflict
damage on the U.S.’s
coastal economies and
ecosystems.
A 51-centimeters (20inches) sea level rise
would inundate wetlands
and drylands on all U.S.
coasts.
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Figure 12.21
Predicted U.S. impacts: Sea level rises
All areas of the U.S. coast
would suffer erosion.
Figure 12.11b,c
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Predicted U.S. impacts: Heat index rises
Two models show big increases in July heat index for the
next 100 years, especially in the central and southeast U.S.
(Heat index combines temperature and humidity.)
Figure 12.13a
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Debate over climate change
Virtually all climate researchers agree that global
climate is changing.
Virtually all climate researchers agree that human
fossil fuel use plays a large role in driving climate
change.
There is uncertainty over other possible factors that
may be involved, and how they might interact with
anthropogenic causes.
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Debate over climate change
There is much debate over what to do about climate change.
• Would costs of reducing greenhouse gas emissions
outweigh costs of climate change?
• Should industrialized nations bear more responsibility
for reducing emissions, or should all nations share
equally?
• Should emissions reduction occur voluntarily, or
through legal, political, or economic pressure?
• How should we allocate funds to reduce emissions and
deal with climate change impacts?
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Viewpoints: Global climate change
Paul
Craig
“Global warming’s threat is
real, huge, and imminent. The
next two decades will be a time
of decision making. The
evidence of global warming is
strong and will get stronger. We
lack good implementation
plans, but these are coming.”
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Bob
Williams
“Weaning humanity from an
economy based on fossil fuels to
one based on non-carbon energy
could wreak worldwide economic
devastation the costs of which, in
human and environmental terms,
could outweigh those of projected
global climate change.”
From Viewpoints
Emissions reduction: More efficient
generation and usage
Electricity generation is the biggest source of greenhouse
gas emissions in the U.S.
So solutions include:
• Improved technology
at plants
• Cleaner-burning
coal
• Energy conservation
by consumers
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Figure 12.15
Emissions reduction: Inefficient autos
Cars use energy very inefficiently. We could do better.
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Figure 12.18
Emissions reductions: Biking and walking
Reducing automobile usage would also lower emissions.
More and more people are choosing to live closer in and
bike or walk to work.
If Americans used public transportation at the rate Europeans
do, the U.S. would no longer need Saudi Arabian oil.
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Figure 12.19
Emissions reductions: International treaties
1992: UN Framework Convention on Climate Change
Voluntary approach
Nations were asked to cut emissions
Failed
1997: Kyoto Protocol drafted:
By 2012 reduce 6 greenhouse gases to below
1990 levels
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Emissions reductions: Kyoto Protocol
The Kyoto Protocol has been ratified by 111
nations so far.
The U.S. is not one of them.
If Russia signs the pact, that will be enough to
make it binding.
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Emissions reductions: Kyoto Protocol
The U.S. administration
has said the treaty is unfair
because it does not force
developing nations like
India and China to share in
the burden of reducing
emissions.
Developing nations say
industrialized nations like
the U.S. created the
problem, so they should
be the ones to take the
lead in cleaning it up.
Supporters and opponents of Kyoto agree, however, that the
treaty alone is not enough to turn around greenhouse gas
production worldwide—it would just slow it down.
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Emissions reductions: Precaution
Because we do not know how bad climate change can make
our lives, should we follow the precautionary principle and
do everything we can to stop it now?
Some say Yes:
Some say No:
Precaution will impede
innovation and economic
growth.
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The stakes are too high to
gamble with our climate.
Conclusions: Challenges
A better idea of natural climate variation in the past will
help quantify the effects we are having now.
Better climate models would help us predict what future
impacts climate change will have.
We need to find and encourage means to reduce emissions,
preferably while not doing economic harm.
We need international agreement to act against climate
change.
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Conclusions: Challenges
Our vehicles, factories, and power plants emit large
quantities of pollutants into our atmosphere.
Photochemical smog plagues most cities.
Industrial smog is a problem in developing world cities.
CFCs have depleted much of Earth’s ozone layer.
Acid precipitation is damaging ecosystems, architecture.
Indoor air pollution is a major health threat.
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Conclusions: Solutions
Scientists continue to devise and carry out creative research
to clarify natural ancient climate variation.
Climate models are getting better, and predictions are
becoming more detailed and reliable.
Many means—conservation, technology, laws and
incentives, consumer choices, renewable energy—exist to
reduce emissions. Proponents must convince skeptics that
these solutions will not mean economic harm.
If the U.S. refuses to ratify the Kyoto Protocol, more strict
treaties will be necessary in the future.
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
Conclusions: Solutions
In developed nations, many outdoor air pollutants have been
reduced, some markedly, by legislation and technology.
Cleaner-running cars could reduce photochemical smog.
Regulations on industry and improved technology have
greatly decreased industrial smog in the developed world.
The Montreal Protocol has halted ozone depletion.
Acid precipitation has stopped getting worse, thanks to
legislation and emission-trading programs.
Being aware of risks, and ventilating spaces, can greatly
reduce dangers from indoor air pollution.
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
QUESTION: Review
Greenhouse gases…?
a.
Absorb incoming ultraviolet radiation.
b.
Absorb infrared radiation released from Earth’s
surface, which later warms Earth’s surface.
c.
Trap air in the troposphere and warm the Earth.
d.
Are translucent and glassy in appearance.
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
QUESTION: Review
Movement of warm water eastward across the Pacific has
been named…?
a. Global climate change.
b. The Milankovitch cycle.
c. El Niño.
d. La Niña.
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
QUESTION: Review
Which conclusion was NOT reached by the IPCC Third
Assessment Report?
a. 1990s were the warmest decade in the past
1,000 years.
b. Birds are migrating earlier in the spring.
c. Sea level has decreased 20 centimeters in 100
years.
d. Mountaintop glaciers are melting back
worldwide.
e. Climate change has caused economic losses.
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
QUESTION: Review
What health effects on people is climate change predicted to
bring?
a. Tropical diseases will move northward.
b. Ozone pollution will increase in cities.
c. Deaths from flooding will decrease.
d. Both (a) and (b) will happen.
e. Both (a) and (c) will happen.
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
QUESTION: Interpreting Graphs and Data
Does having the blue data (ancient climate change) tell you anything
about the red data (change since 1860)?
a. No; they represent
different time periods.
b. Yes; it shows that the red
increase is unusual.
c. Yes; it shows that the red
increase is not unusual.
d. No; the blue and red data
do not line up in the years
they overlap.
Figure 12.9b
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
QUESTION: Viewpoints
Should we take steps to avoid further climate change?
a. Yes; it is a grave threat.
b. Yes; we should follow the precautionary
principle.
c. No; it would cause too much economic harm.
No; there may be just as many benefits from
climate change as harmful effects.
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
QUESTION: Review
Which atmospheric layer contains the gases we breathe and
is responsible for the weather we experience?
a. Troposphere
b. Thermosphere
c. Stratosphere
d. Mesosphere
e. Tropopause
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
QUESTION: Review
Which pollutant is involved when air pollution over cities
interacts with sunlight, heat, oxygen, and other chemicals?
a. Nitric oxide
b. Nitrogen dioxide
c. Tropospheric ozone
d. All of the above
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
QUESTION: Review
Which statement about acid precipitation is FALSE?
a. It alters soil chemistry.
b. It damages buildings and statues.
c. It can occur far from the source of its pollutants.
d. It can kill trees.
e. It did not occur until 1970.
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
QUESTION: Review
Which are thought to be the most severe indoor air pollution
threats in developed and developing nations, respectively?
a. Indoor cooking fires; radon
b. Pesticides; cigarette smoke
c. Cigarette smoke; indoor cooking fires
d. Industrial smog; carbon monoxide
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
QUESTION: Weighing the Issues
Look around your classroom or lecture hall. What changes
might you suggest to improve indoor air quality?
a. Open windows or otherwise increase
ventilation.
b. Remove certain products, materials, or items.
c. Get tests run for radon, lead, or asbestos.
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
QUESTION: Interpreting Graphs and Data
Temperatures decrease with increasing altitude in the…?
a. Stratosphere and
thermosphere
b. Troposphere and
mesophere
c. Stratosphere and
tropopause
Tropopause and
ozone layer
Figure 11.3
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings