Global Warming
Applied Chemistry
Global Warming Video Clip
Global Warming
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Global warming is the increase in the
temperature of the Earth due to the
increase in greenhouse gases.
Solar radiation is radiation from
the sun.
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About 30% of incoming solar radiation is reflected
back into space by clouds and particles.
47% is absorbed to warm the atmosphere, oceans,
and land.
23% powers the hydrologic cycle or water cycle.
Greenhouse Gases
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The hydrologic
cycle is the
continuous cycling
of water into and
out of the
atmosphere by
evaporation and
condensation.
Greenhouse Gases
Earth’s warmed surface reradiates the
absorbed radiation at lower energies as
infrared radiation.
 Some molecules in the atmosphere
absorb this lower energy.
 This traps and returns the radiation to
the atmosphere.
 This is known as the greenhouse effect.
 These atmospheric molecules, or gases,
are known as greenhouse gases.
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Solar radiation
planet’s
atmosphere
contains
greenhouse gases
Solar radiation
passes through the
gases
Solar radiation
warms the surface
of the earth and
heat rises from the
surface.
Some heat is able
to pass throughout
the gases.
Some heat cannot
pass through,
adding to the
overall
temperature.
Greenhouse Gases
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Greenhouse gases trap heat from the Sun
on the Earth’s surface causing the
temperature of the earth to rise.
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The most abundant greenhouse gas is
water which is mostly naturally occurring.
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Other greenhouse gases include carbon
dioxide, methane, nitrous oxide, and
chlorofluorocarbons (CFCs and HFCs).
Greenhouse Gases
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Most greenhouse gases occur naturally.
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The increase in the amount of greenhouse
gases is due to human activity.
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Anthropogenic means man-made.
U.S. Anthropogenic Greenhouse
Gas Emissions by Gas 2006
(Million Metric Tons of Carbon Dioxide Equivalent)
http://www.eia.doe.gov/bookshelf/brochures/greenhouse/Chapter1.htm
Carbon Dioxide (CO2) - colorless,
odorless nonflammable gas
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The most prominent
greenhouse gas in
earth's atmosphere
Results from the
combustion of
petroleum, coal, and
natural gas
Deforestation is
logging for lumber,
pulpwood, and fuel
wood.
http://www.umich.edu/~gs265/society/greenhouse.htm
Methane - colorless, odorless,
flammable gas
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Methane comes from landfills,
coal mines, oil, natural gas, and
agriculture
It represents 9% of total
emissions.
It is formed when plants decay
and where there is very little
air. It is often called swamp gas
because it is abundant around
water and swamps.
Bacteria that breakdown organic
matter in wetlands and bacteria
that are in the gut of animals
(cows, sheep, goats, buffalo,
termites, camels) produce
methane naturally.
It stays in the atmosphere for
only 10 years, but traps 20 times
more heat than carbon dioxide.
Since 1750, methane has
doubled, and could double
again by 2050.
In one day, a cow can
emit ½ pound of methane
into the air.
Nitrous oxide (N2O) – colorless
gas, sweet odor
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Nitrous oxide is emitted
through the use of
nitrogen fertilizers, from
burning fossil fuels,
disposing of human and
animal waste in sewage
treatment plants,
automobile exhaust
5% of total emissions
Anesthetic - deadens pain
 aka “laughing gas”
Nitrous oxide released
today will still be trapped
in the atmosphere 100
years from now.
Nitrous oxide gas has risen by
more than 15% since 1750.
Chlorofluorocarbons (CFCs) and
Hydrofluorocarbons (HFCs) - nonreactive,
nonflammable gases and volatile liquids.
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CFCs are used in aerosol cans, refrigerators, and air
conditioners.
In 1978 CFCs were banned in the US. In 1987, over
180 countries signed the Montreal Protocol to ban CFCs
The substitute for CFCs are hydrofluorocarbons (HFCs).
 HFCs do not harm or breakdown the ozone molecule,
but they do trap heat in the atmosphere, making it a
greenhouse gas, aiding in global warming.
 The way to reduce emissions of this gas is to be sure
that in both devices the coolant is recycled and all
leaks are properly fixed . Before throwing the
appliances away, be sure to recover the coolant in
each.
http://www.nocfcs.org/
Greenhouse Gases
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Earth’s average surface temperature is
15°C (59°F) due, in part, to the presence of
water and carbon dioxide.
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Without these gases, Earth’s surface
temperature would be -18°C (0°F).
Causes for increased gas levels
Deforestation
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Tree use carbon dioxide from the
atmosphere to make food.
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Trees are being cut down for development
and other uses.
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Because less carbon dioxide is removed, the
amount of carbon dioxide in the atmosphere
increases.
Plant a Tree!!!
 One
tree can absorb as much
carbon dioxide in a year as a car
produces driving 26,000 miles.
 A single tree produces
approximately 600 pounds of O2 a
year. That means two mature
trees can supply enough O2
annually for a family of 4
Causes for increased gas levels
Burning Fossil Fuels
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Fossil fuels include coal, natural gas, and
petroleum, also known as crude oil.
Fossil fuels originate from plants and animals.
Pressure, heat and microbes convert once living
matter into fossil fuels over millions of years.
Fossil Fuels contain carbon.
When burned, they produce water and carbon
dioxide, two greenhouse gases.
Affects of Global Warming on
the Environment
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Increase temperature of the Earth.
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Increase melting of the ice caps, which results in
a higher sea level.
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Coastal areas will be affected by higher sea
levels.
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Changes to climate patterns on Earth.
 Climate change
= Precipitation patterns, storm
severity, and sea level
Affects of Global Warming on
the Environment
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Salinity of the ocean is disturbed.
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Salinity is the concentration of dissolved
salts.
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A change in salinity creates problems for
marine life.
Ways to Combat Global Warming
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Find alternative energy
sources, “green sources.”
Green energy sources do
not contribute to the
production of greenhouse
gases.
Green energy sources
include solar energy, wind
energy, hydroelectric
energy, and nuclear energy.
Ways to Combat Global
Warming
 Recycle
paper, plastics, and
aluminum products.
 Conserve energy.
Video
“Kill A Watt”
http://home.howstuffworks.com/question151.htm
The Renaissance of Nuclear Power
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Oil is used to produce fuels and as a starting
material for the production of medicines,
carpet, clothing, plastics, and artificial
limbs.
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Currently, about 50% of total energy needs
in the US are met by burning oil.
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Burning oil increases the level of
greenhouse gases.
The Renaissance of Nuclear Power
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There is an increase in the demand for oil
worldwide.
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Costs for oil are increasing.
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Oil is a nonrenewable resource.
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There is an increased demand for energy
today and for the foreseeable future.
What Is Renewable Energy?
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Renewable energy sources can be replenished in a
short period of time. The five renewable sources
used most often are:
 Biomass
— including wood and wood waste, municipal
solid waste, landfill gas, and biogas, ethanol, and
biodiesel
 Water (hydropower)
 Geothermal
 Wind
 Solar
The Clean Truth
About Nuclear
Coal
Oil
Natural
Gas
271
222
150
Nuclear
0
Greenhouse Gas Emissions:
• A 1,000 MW plant emits this many metric tons of
CO2 every hour based on its fuel
The Renaissance of Nuclear Power
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Nuclear power plants do not contribute to
the production of greenhouse gases.
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Nuclear power plant safety has been
improved since the accidents at 3-Mile
Island and Chernobyl.
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More energy is generated by a nuclear power
plant than that by a coal-fired plant based on
per gram of fuel used.
Sustainable Development
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Sustainable Development is the
development that meets the needs of the
present without compromising the ability
of future generations to meet their own
needs.
Sustainable Energy involves
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Development of new technologies
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Energy efficiency
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Conservation
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Expanded use of nuclear energy.