A current world debate

1
Climate Change

• A current world debate

2
Colorado State Standards

• Colorado Prepared Graduate Competencies
• Evaluate evidence that the Earth is a complex
  system of interactions between the geosphere,
  atmosphere,
• hydrosphere and biosphere.
• Concepts and Skills students know include
• 4. Climate is the result of energy transfer among
  interactions of the atmosphere, hydrosphere,
• geosphere, and biosphere.

Inquiry How have climate changes impacted
human society? Why are there different climates
on Earth? How can changes in the ocean create
climate change? How have climates changed over
Earths history? How are humans potentially
impacting Earths climates? How might global
warming impact all of Earths systems?
3
The climate change Debate

• Not debated Climate has always changed
  throughout Earths history.
• Debated

Current climate change is due to man made causes.
Current climate change is a part of Earths
natural cycle.
Versus
In this lesson we will look at both sides of the
debate
4
Review Green House Effect

• Without the greenhouse effect are planet would be
  cold and uninhabitable.

5
Interpreting CO2 Data Part 1

• Graph CO2 data set.
• This dataset from Mauna Loa is
• the most complete and accurate CO2 dataset
  in the world. CO2 is measured in parts per
  million 316 parts per million means that for
  every 1 million particles in the atmosphere, 316
  of those are
• carbon dioxide molecules.
• Year should be on the x-axis and CO2 emissions on
  the y-axis. The scale should be appropriate for
  the data.

• Include all graph requirements
• (title, labeled axis, etc)
• Line Graph (2 lines 2 different colors)
• Answer questions on the back of graph.

6
Analysis Conclusions

• What might account for differences in the CO2
  concentrations measured in May and October of
  each year?
• Based on the data shown on your graph, what do
  you think the carbon dioxide concentration will
  be in the year 2020?
• Why do you think carbon dioxide levels have
  continued to rise during the past 45 years?
• What types of activities might raise carbon
  dioxide levels even faster?
• How do you think this will affect Earths climate?

7
Is current climate change man made?
8
Analysis Conclusions

• What conclusions can you draw from this graph?
• Is the graph appropriate to make these
  conclusions?

9
Arguments For Human Caused Climate Change (Global
Warming)

• FACTS
• The burning of fossil fuels and the clearing of
  forests release carbon dioxide (CO2) into the
  atmosphere.
• Carbon dioxide and other greenhouse gases in the
  atmosphere trap heat through the greenhouse
  effect.
• Earth is warming because these gasses are being
  released faster than they can be absorbed by
  natural processes.
• It is very likely (greater than 90 percent
  probability) that human activities are the main
  reason for the world's temperature increase in
  the past 50 years.
• The rate of change in temperature is greater than
  and change in geological history.

10
Arguments For Human Caused Climate Change (Global
Warming)

• Scientists know with very high confidence, or
  even greater certainty, that (greater than 90
  percent probability)
• It is very likely that human activities are the
  main reason for the world's temperature increase
  in the past 50 years.
• Human-induced warming influences physical and
  biological systems throughout the world
• Sea levels are rising
• Glaciers and permafrost are shrinking
• Oceans are becoming more acidic
• Ranges of plants and animals are shifting

11
Arguments Against Human Caused Climate Change
(Global Warming)

• Natural part of Earths cycle of climate changes.
• The temperature increase is very small especially
  when it is spread over a century.
• The earth was warmer before. That did not have
  harmful consequences on humans.
• The increase in temperature will help plants grow
  in currently cold and uninhabitable areas.
• The increase in the level of carbon dioxide will
  stimulate plant growth.
• Steps to limit global warming will decrease
  economic growth and hurt the poor.
• People in fossil fuel industries will lose their
  jobs.
• Rise in carbon dioxide levels has always come
  after a temperature change and not before.
• The upsurge in solar activity in the sun has
  caused global warming.
• Water vapor plays a major part in global warming.
  It is argued that man made emissions like carbon
  dioxide has only minor effects.
• The global warming is a natural phenomenon. Man
  has no role to play in it. Only our environment
  is responsible.

12
U.S. survey based on the opinions of 3,146
scientists.

• Two questions were key
• Have mean global temperatures risen compared to
  pre-1800s levels.
• Has human activity been a significant factor in
  changing mean global temperatures?
• 90 percent of the scientists agreed with the
  first question and 82 percent the second
• The strongest consensus on the causes of global
  warming came from climatologists who are active
  in climate research, with 97 percent agreeing
  humans play a role.
• Petroleum geologists and meteorologists were
  among the biggest doubters, with only 47 percent
  and 64 percent, respectively, believing in human
  involvement.
• Study done by University of Illinois