Download Global Warming

Global Warming
Erin Lee
Wes Ehninger
Lannie Davis
Laura Burns
What is Global Warming?
 The Earth's surface temperature has risen by about 1 degree
Fahrenheit in the past century, with accelerated warming during
the past two decades.
 There is new evidence that most of the warming over the last 50
years has been attributed to human activities.
 Human activities have altered the chemical composition of the
atmosphere through the buildup of greenhouse gases – primarily
carbon dioxide, methane, and nitrous oxide.
 Since 1980, we have experienced 19 of the 20 warmest years on
record; all three of the hottest years ever recorded have taken
place since 1998.
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 Global warming has been particularly strong over the past 20
years.
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The Greenhouse Effect
 Since the beginning of the industrial revolution, Carbon dioxide
concentrations have increased by 30%, methane concentrations
have more than doubled, and nitrous oxide concentrations have
risen15%.
 These increases have enhanced the heat-trapping capability of
the earth’s atmosphere.
 Energy from the sun drives the earth’s weather and climate and
heats the earth’s surface. The earth then radiates energy back into
space. Atmospheric greenhouse gases (water vapor, carbon
dioxide, and other gases) trap some of the outgoing energy,
retaining heat somewhat like the glass panels of a greenhouse
 This is how we get the “Greenhouse Effect”
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Cont…
 Without this natural “greenhouse effect,” temperatures
would be much lower than they are today making life
impossible. Because of greenhouse gases, the earth’s
average temperature is about 60 degrees Fahrenheit.
 However, problems may arise when the atmospheric
concentration of greenhouse gases increases.
 The key greenhouse gases emitted by human activities
remain in the atmosphere for periods ranging from
decades to centuries.
 Greenhouse gases trap heat in the Earth's atmosphere
and in turn warm the planet.
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What has this produced?
 The planet has warmed up by 1°F since the
late 19th century and it will only get worse.
 Warming has occurred in both the northern and
southern hemispheres, and over the oceans.
 This has been proven by looking at melting
glaciers, decreased snow cover in the northern
hemisphere, and also even by warmth
underground
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Is the damage already
done or is there still
hope?
* IF we don’t act now, our children
will inherit dirtier water and air, a
hotter world that has more droughts,
wildfires and more severe floods *
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CONSEQUENCES of global warming…
climate pattern changes, droughts and wildfires, intense
rainstorms, melting water, sea levels rising and species die-off
 The global temperature
increased by 1 degree
Fahrenheit over the last
century and potentially will
increase more rapidly in
future centuries.
 The Earth has experienced 19
or its 20 hottest years on
record, with 1998 the hottest
and 2002 and 2003 ranking in
second and third.
 In 2002, the Western US had
its second worst wildfire
season in the last 50 years.
More than 7 million acres
burned and Colorado, Arizona
and Oregon had their worst
seasons ever.
Dry Conditions produced
the worst wildfires in
Florida in 50 years.
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 Warmer temperatures increase the energy of the climatic
system and lead to a greater number of rainfall. National
yearly rainfall increased between 5 and 10 % since the
20th century because of the heavy downpour in some
areas.
 Rising Global Temperatures will speed up the process of
melting glaciers and cause early ice thaw on lakes and
rivers. At the current rate of melting, all of the glaciers
located in the Glacier National Park will be completely
gone by 2070.
 Because of melting ice and glaciers, the current pace of
sea-level rise is more than three times the historical rate
and is accelerating.
The satellite photo above shows the Larson B ice shelf on Jan. 31, 2002. Ice appears as
solid white. Moving to the right, in photos taken Feb. 17 and Feb. 23, the ice begins to
disintegrate. In the photos at far right, taken Mar. 5 and Mar 7, see water (blue) where
solid ice had been in the past, and that a portion of the shelf is drifting away. Photos:
National Aeronautics and Space Administration.
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 Over the past 25 years,
there has been a 33%
shrink of some penguin
populations in parts of
Antarctica due to the
decline in winter seaice habitat.
 In Washington’s
Olympic Mountains,
sub-alpine forest has
invaded higher
elevation alpine
meadows. In Bermuda
as well as other places,
forests are being lost.
Warmer temperatures are causing some
ecosystems, including alpine meadows in
the Rocky Mountains, (pictured) to
disappear slowly but surely.
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Greenland
Glaciers along the southeastern coast of Greenland are thinning
by more than 3 feet a year – many believe because of global
warming, according to a new study by NASA scientists.
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The entire US will warm, though sulfates could
limit the warming in areas. Scientist are not
able at this time to say which parts of the US
will become drier or wetter. But the trend is
expected to be one that goes towards increased
precipitation and evaporation as well as more
intense rainstorms and much drier soils. As of
right now though, the potentially most crucial
impacts depend upon whether rainfall
increases or decreases, which is hard to
project for certain areas. Also, a lot of damage
has been done, but depending upon the role we
take in the future, many of the worst long term
consequences of global warming could still be
on their way.
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Global Warming Impacts

A study done by U.S. Market
Consequences of Global Climate
Change, found that any species
or ecosystem that is less able to
adapt- for example coral reefs,
coastal wetlands, already
endangered species, and alpine
forests- is at the greatest risk.

The southeast and the Southern
Great Plains are at most risk due
to their low-lying coasts and the
impacts of warmer conditions on
agriculture.

Laura Burns
Impacts of Global
Warming on People

The effects of climate on people may
vary…

Economically devolved societies, like
those in North America, Europe and
Japan, could use technology to
reduce impacts.

For example, they might develop new
crop varieties, construct new water
systems, and limit coastal
development. Some northern
countries, such as Canada and
Russia, might even benefit from
longer growing season and lower
heating bills if the climate becomes
warmer.

Laura Burns
Impacts of Global
Warming on People

In contrast, economically less
developed societies, like those in
parts of Africa, Asia, and South
America depend much more directly
on climate, and could be hit much
harder by sudden or larger changes.

Places like coastal Bangladesh and
low-lying islands, could be flooded by
storms or rising sea level.

Droughts in Africa might become
more serious.

Laura Burns
Impacts of Global
Warming on People

Developing countries have far fewer
resources for adapting to such
changes.

They may not be able to afford large
projects such as sea walls or
aqueducts. Peasant farmers may
have difficulty adopting new
agricultural practices.

The resulting social tensions could
lead to more political unrest and
large-scale migrations.

Laura Burns
Impacts of Global Warming
on the Natural Environment
 Plant migration: Climate
may change faster than plants
can move from one region to
another. This may cause
species extinction, lower
biodiversity, and changes in
the way species interact.
 Coral reefs: Slightly warmer
tropical water may kill the
algae which reef animals use
for food.

Laura Burns
Impacts of Global Warming
on the Natural Environment


Changes in insect pests:
Climate change can affect the
number and kinds of pests directly. It
can also affect them by changing the
mix of plant varieties and their
nutrient content. This can influence
plant survival, food chains, and the
spread of disease.

Mangrove swamps: Mangrove
swamps are important breeding
grounds for many animals that live in
water. Increased ocean flooding may
damage these areas by changing the
supply of nutrients and the amount of
salt.

Laura Burns
Actions Taken to Prevent
Global Warming
Governments can adopt a range of options
for reducing greenhouse gas emissions,
including:
-increasing energy efficiency standards
-encouraging the use of renewable energy
sources (such as wind and solar power)
-eliminating subsidies that encourage the
use of coal and oil by making them artificially
cheap
-protecting and restoring forests, which serve
as important storehouses of carbon
W.E.
What can Individuals Do?
 Individuals can reduce the need
for fossil fuels and often save
money by:
 driving less and driving more fuelefficient and less-polluting cars
 using energy-efficient appliances
 insulating homes
 using less electricity in general
W.E.
U.S. Response to Global
Warming
 29 States have completed or are
working on action plans to
reduce Greenhouse Gas
emissions.
 States have access to a “state
action list” to see what other
states are implementing to
reduce emissions.
 Implementation of the Energy
Star program, an initiative to
reduce CO2 emissions by
businesses and industry.
W.E.
Kyoto Treaty
 U.N. Sanctioned
International Agreement
to reduce climate
changing gasses in 1997
 Called for vast reduction
in U.S. emissions
 Bush Administration
refused to sign treaty,
arguing it would
devastate American
industry and business.
W.E.
What else can be done?
 “Fortunately, a number of analyses indicate that current
technologies do have the capability to reduce
emissions in the next few decades by very large
amounts, thus enhancing the ability of our generation
and those that follow to stabilize concentrations at
levels as low as 450ppm. The "toolbox" of current
lower carbon technologies is well-known: substantial
reductions in energy consumption by vehicles,
appliances, buildings and the megalopolises they form
are achievable without any loss in services15;
renewable resources like wind, solar and biomass are
already cost-competitive in certain applications…”
(www.nrdc.org)
W.E.
Sources
 http://www.marshall.org/article.php?id=67#1
 http://www.epa.gov/globalwarming/
 http://www.earthinstitute.columbia.edu/crosscut
ting/climate.html
 http://yosemite.epa.gov/oar/
 http://nrdc.org/globalwarming/fcons.asp
 (www.prweb.com/releases/2004/4/prewebxml1
21971.php)
 www.gcrio.org/gwcc/part2.html