Exploring Climate Change

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Exploring Climate Change

• Open the PowerPoint presentation Exploring
  Climate Change.
• View the slide show (slide numbers are indicated
  in the boxes).
• Part 1 Changing Global Climate
• Global temperatures have warmed and cooled many
  times throughout the Earths history. It is
  concerning, however, that Earths temperatures
  are warming faster now than any time before. The
  dramatic increase in greenhouse gasses like
  carbon dioxide are largely to blame.
• Despite the fact that the overall temperature of
  the earth is rising, some scientists prefer the
  term climate change to global warming. This is
  because the climate story is a complex one. Some
  places are heating rapidly, while others have not
  shown significant warming. Many places are
  experiencing dramatic changes in precipitation as
  well. Extreme weather events are also becoming
  more common.
• This chart illustrates temperature anomalies
  (variations from normal values) for 2006. The
  larger the circle, the greater the anomaly.
• Part 1 QuestionsWhat part of the world
  (continent and country) experienced below average
  temperatures in 2006? (Use Google Earth if you
  need help identifying countries) Asia / Russia
• Where were the two hottest zones in 2006?
  Provide the continent and a country for both
  responses. Answers will vary
• 1. North America / Canada
• 2. Central Asia / Iran
• This chart illustrates precipitation anomalies
  (variations from normal values) for 2006. The
  larger the circle, the greater the anomaly.

PPT SLIDE NUMBER
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Exploring Climate Change
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Name two regions of the world that experienced
above average precipitation in 2006? Provide
specific answers such as The Yucatan Peninsula
of Mexico (Use Google Earth if you need help
identifying countries). Answers will vary 1.
Caribbean / Dominican Republic 2. Southern
India Is there more variation on the temperature
or the precipitation map? Precipitation Earth
s climate is extremely complex. While there were
many examples of global warming in 2006, there
were other types of climate anomalies. Study the
chart and list one of the anomalies that you
would not find if every location in the world was
warming at a consistent and uniform rate.Answers
will vary. Coldest temperatures in Moscow in 30
years List one example of an extreme weather
event from 2006. Answers will vary. Hurricane
Sergio strongest November hurricane since
1991. Climate change is not a uniform
process. In other words it affects different
locations at different rates and can vary
significantly from year to year. 2006 was an
extremely hot year in the United States. In fact
it was the hottest year in recorded history for
the US. It was the sixth hottest year in
recorded history for the world. What state had
its warmest year on record in 2006? (Use Google
Earth if you need help identifying states) New
Jersey Even the coolest state, California, had
a year that was warmer than 87 of the last 112.
How many years have been hotter than 2006 in
Oklahoma? One Like the global maps,
precipitation shows much more variation than
temperature. Some parts of the US were very dry
while others were very wet. What region of the
US was very wet in 2006? The Northeast
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Exploring Climate Change
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What states had years that were among their five
driest? Florida, Georgia, Wyoming, North Dakota
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Part 2 Glacier National Parks Disappearing
Glaciers Repeat photography has become a valuable
tool for communicating effects of global warming,
including the decline of the parks namesake
glaciers. With evidence of worldwide glacial
recession and modeled predictions that all of the
parks glaciers will melt by the year 2030, USGS
scientists have begun the task of documenting
glacial decline through repeat photography. The
striking images created by pairing historic
images with contemporary photos has given global
warming a face and made climate change a
relevant issue to viewers. Examine the following
sets of photographs used in the Glacier National
Park repeat photography project. Then answer the
questions that follow.
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Part 2 Questions After examining the previous
slides what is the general trend for glaciers in
Glacier National Park? Decreasing in
size. After examining the previous slides what
would be your estimate of the percentage decline
of glaciers in Glacier National Park during the
last century? (If you answered 10 to this
question, you would be saying that the glaciers
today are approximately 90 of their size in the
year 1900) Approximately 70 When do scientists
think that all of the glaciers in Glacier
National Park will be gone? 2030 What is the
technique, method, or tool used for this set of
photographs? Repeat Photography Think of at
least one other way this technique could be used?
In other words, what is another type of change
that could be documented using this method?
Answers will vary. You could document increase
or decrease in tree density in a forest.
Exploring Climate Change
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• Now start Google Earth.
• Under Tools, and Options make sure the
  elevation exaggeration is set to 1.
• Type Glacier National Park in the Fly To box.
  
• Look around the park and see if you can find
  some of the glaciers.
• What do you find in many of the glacial cirques
  instead of glaciers? (If you dont know what a
  cirque is, you will need to go to
  www.wikipedia.org and search for glacial
  cirque) Try to provide the correct landform
  term for this answer instead of a general answer.
  Lake or Tarn

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Part 3 Diminishing Sea Ice Sea ice is simply
frozen ocean water. It forms, grows, and melts
in the ocean. In contrast, icebergs, glaciers,
ice sheets, and ice shelves all originate on
land. Sea ice occurs in both the Arctic and
Antarctic. Sea ice grows during the winter
months and melts during the summer months, but
some sea ice remains all year in certain regions.
About 15 percent of the world's oceans are
covered by sea ice during part of the year. Even
though sea ice occurs primarily in the polar
regions, it influences our global climate. Sea
ice has a bright surface, so much of the sunlight
that strikes it is reflected back into space. As
a result, areas covered by sea ice don't absorb
much solar energy, so temperatures in the polar
regions remain relatively cool. If gradually
warming temperatures melt sea ice over time,
fewer bright surfaces are available to reflect
sunlight back into space, more solar energy is
absorbed at the surface, and temperatures rise
further. Satellites have shown the fluctuation
in sea ice from year to year since 1972. Data
suggest that since then, Arctic ice has been
decreasing at an average rate of about 3 percent
per decade, while Antarctic ice has increased by
about 0.8 percent per decade.
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Examine these images of sea ice extent from
December of 2006. Part 3 QuestionsIs the
December 2006 sea ice extent more or less than
its December average (median) in the Arctic?
Less Is the December 2006 sea ice extent more
or less than its December average (median) in
Antarctica? Less In what month would you
expect the Arctic sea ice to be at its greatest
extent? March the end of winter
Exploring Climate Change
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In what month would you expect the Antarctic sea
ice to be at its greatest extent? September
the end of the southern hemisphere winter How
does sea ice help keep the Earth cool? It
reflects sunlight In recent decades, has Arctic
or Antarctic ice been diminishing more rapidly?
Arctic, Antarctic has been slightly increasing
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Part 4 Rising Sea Level Multiple complex
factors may influence an increase in sea level.
The sea has risen more than 120 meters since the
peak of the last ice age about 18,000 years ago.
The bulk of that occurred before 6,000 years ago.
From 3,000 years ago to the start of the 19th
century sea level was almost constant, rising at
0.1 to 0.2 mm/yr since 1900 the level has risen
at 1 to 3 mm/yr since 1992 satellite altimetry
indicates a rate of about 3 mm/yr. This change
may be the first sign of the effect of global
warming on sea level. Global warming is
predicted to cause significant rises in sea level
over the course of the twenty-first century. Part
4 QuestionsLook at the charts above, how would
you describe the relationship between recent sea
level rise and global temperatures? As
temperatures increase, sea level rises.
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Sea level rise will be a serious problem in many
parts of the world in coming years. Study these
maps displaying what areas of North America will
be inundated by 1 and 3 meter sea level
rises. Based on these maps, what two states would
be most severely affected by moderate sea level
rise? Florida and Louisiana What island
country would be nearly totally submerged by a 3
meter rise in sea level? (You may need to use
Google Earth to determine the name of the
country) Bahamas
Exploring Climate Change
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This chart illustrates that a 100 meter change in
sea level has happened in geologically recent
times. Find the point on the chart where
change was occurring most rapidly. When was this
period of rapidly rising water? 13,000 to 15,000
years ago What was happening at that time to
cause the sea to rise rapidly? Last ice age was
ending and the glaciers and continental ice
sheets were melting. Based on parts one and two
of this exercise, what is happening now? Glaciers
and sea ice are melting.
Exploring Climate Change
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