Transcript Climate_Change_Power_Point

Climate Change
Amy Urling
Science Teacher
Northfield High School
Hurricane Irene (August 2011)
Ms. Urling’s Disclaimer
• Be careful where you get your information:
(for example: don’t rely on websites such as
DHMO.org)
• All of the information presented in this Power
Point are facts and come from:
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science textbooks
scientific government organizations
scientific peer-reviewed journals
or Ms. Urling’s own observations.
• Watch the video:
http://video.nationalgeographic.com/video/101videos/global-warming-101
In 2011, there were more than a dozen
weather events costing more than $1 billion
Tornadoes
Glacier National Park - Montana
• In 1850, Glacier National Park had 150 glaciers. Today it
has only 25.
• Scientists predict all the glaciers will be gone by 2020
Mt. Kilimanjaro
Glacier Bay National Park - Alaska
Margerie Glacier
Glacier Bay National Park (July 2009)
Ecotourism
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Denali National Park - Alaska
The tree line in Denali National Park has
increased in elevation. Taiga forests are now
found where tundra used to be prevalent.
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Taiga
Urling 09
Tundra
Changes in Ecology
Because of
warmer
winters in the
West, pine
beetles are
killing large
areas of
forests in
Wyoming,
Montana,
Colorado,
California and
Idaho
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Flat Creek Ranch, Wyoming – August 2008
Global Mean Sea Level
Polar Bears and Disappearing Sea Ice
Polar bears were the first species listed on the
Endangered Species List (2008) due to the
effects of global warming
Why do we look at long term trends and not just 3 – 4 years of data?
Polar Bears and Disappearing Sea Ice
Polar bears were the first species listed on the
Endangered Species List (2008) due to the
effects of climate change
Arctic Albedo Feedback
The Arctic
climate is
warming rapidly
and will have
worldwide
implications. As
ice/snow melts,
darker land is
exposed which
absorbs even
more heat
(what type of
feedback system
is that?)
Weather vs. Climate
• Weather: day-to-day variations in temperature,
air pressure, wind, humidity, and precipitation –
all mediated by the atmosphere
• Climate: result of long-term weather patterns in a
region
• Climate Change: does not involve daily
changes in weather – it involves changes in
long-term weather patterns!
• Climate Change vs. Global Warming???
Misconceptions About Climate Change
Some people might say that global warming
isn’t true because:
• It snowed on April 27, 2010.
• Vermont had a really cold summer last
year.
• There was only one major hurricane this
year.
• This past winter was colder compared to
the year before.
Other Factors Affecting Global
Temperatures
• Cloud cover: cooling
• Particulates: cooling
• Volcanic activity: cooling
– When Mount Pinatubo in
the Philippines in 1991,
sulfur dioxide and other
gases emitted into the
atmosphere circled the
globe, reduced sunlight
reaching the Earth’s
surface, and decreased
levels of protective ozone
for 15 months
Natural Causes of Climate Change
• Why does climate change naturally?
– The Earth is like a wobbling top with an elliptical orbit around the sun.
• Three kinds of changes occur.
– (1) Earth is unable to keep its poles at a constant angle in relation to
the sun. The wobble makes a complete cycle in 26,000 years.
– (2) The tilt of wobble also varies over a period of 41,000 years
– (3) The elliptical orbit around the sun also changes. Sometimes it is a
more extreme ellipse; other times it is closer to a circle and this occurs
over 100,000 years.
CO2 Data from Mauna Loa, Hawaii
401.52
Why does
the graph
have a
zig-zag
pattern?
How Do We Know What Temperatures and
Gas Levels Were Like in the Past?
• Tiny bubbles of ancient atmosphere in ice
cores extracted from ancient glaciers
• Analyzing radioisotopes in rocks and
fossils
• Plankton ocean sediment
• Pollen
• Tree rings
• Historical records
Carbon Dioxide and Temperature
Levels of CO2 correlate directly with temperature
Sources of CO2 Emissions
China recently
passed the U.S. in
total CO2 emissions,
however, each
American releases
much more CO2
than the average
Chinese
Intergovernmental Panel of Climate
Change (IPCC)
• Established in 1988 by the United Nations and World Meteorological
Organization to document past climate changes and project future
changes based on science. 195 countries are members.
• Issued reports indicating that:
– It's "extremely likely (95% probability)," that human influence,
primarily the burning of fossil fuels, has been the dominant
cause of global warming over the past several decades.
– Warming is “unequivocal,”. The Earth is the hottest it has been
in 400 years.
– Arctic temperatures are rising faster than the rest of the Earth.
– Glaciers and sea ice are melting at increasing rates.
– Not-so-permanent permafrost is melting, releasing CO2 and CH4
– Sea level is rising and oceans are becoming more acidic.
– Warmer oceans will fuel stronger storms.
– Plants and animals are more vulnerable than humans.
– We must phase out fossil fuels by 2100.
IPCC Assessments
• Global climate change IS occurring
• Human activities ARE influencing global climate change
• The Earth’s temperature will increase by 2.4 – 5.4°C (4.5 – 9.7°F)
by 2100 (some areas may become warmer, some areas may
become colder).
• Global impacts will be unprecedented and severe
– Heat waves more frequent and last longer
– Widespread water concerns – increase in extremes (floods and
droughts)
– Rising sea levels
– Increase in storm intensities
– Significant losses in crop yields
– Mass migration of people
– 2–20% of species are likely to be at increased risk of extinction
– Human health effects (diseases)
Potential Effects of Climate Change
• Rising Sea Levels
– A major warming could increase sea levels
because of :
• 1. Expansion of liquid water as water warms
• 2. Melting of ice sheets on land whose waters
then flow into the ocean.
– About half the people on Earth live in coastal
areas.
– As population rises, the number of people
vulnerable to coastal flooding increases.
• Rise in sea level could:
– Threaten island nations (like the Maldives)
– Increase coastal erosion on open beaches
and cause property loss.
– Lead to loss of coastal wetlands
– Threaten ground water supply in coastal
communitie
The world’s smallest nation, Tuvalu,
is only 4.5 meters above sea level
More Potential Effects of Climate Change
• Agricultural Productivity
– Globally, agriculture production is likely to
increase in some regions and decline in
others.
– Some areas may become ore arid.
– A climate shift could have serious negative
effects on food production.
• Human Health Effects
– Health status of millions of people could
potentially be affected through
• Increases in malnutrition
• Increased deaths, diseases, and injury due to
extreme weather events
• Increased diarrhea diseases
• Increased frequency of insect-born diseases
How could climate change
affect Vermont?
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The Facts About Dealing With Climate
Change
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The problem is occurring on a global level
The effects will last a long time
The problem is a long-term political issue
The harmful and beneficial impacts are not
spread evenly
• Many actions that might reduce the threat of
climate change, such as phasing out fossil
fuels, are controversial because they can
disrupt economies and lifestyles
• It’s definitely an uphill battle
Comment on one of the following quotes:
“It’s about time for denial to come to an end. We’re no longer
talking about theory, about computer models of what might
happen. We’re talking about what is happening, all around the
world, with almost unimaginable speed”
Bill McKibben (world-famous environmental writer from
Middlebury, VT)
“If scientists are right about global warming, then acting to slow
climate change is acting responsibly. If they are wrong, then we
will have reduced air pollution, protected human health, reduced
dependence on foreign oil, made the U.S. economy less
vulnerable to oil shocks, and become a worldwide leader in new
energy technologies. What are we waiting for?”
Fred Krupp president of Environmental Defense