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lesson 9 |
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| Teachers' notes |
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| This
is not intended to be a lesson about global warming.
It is assumed that students are already aware of
what the Greenhouse Effect and the causes of global
warming. |
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| Starter |
The PowerPoint
presentation on ‘A journey to Venus’ When you have
finished with the first slide, click the mouse for
the next slide and then leave, it will continue
on its own until the first information page (after
the space probe has crashed). Then click for the
next page until ‘The Greenhouse Effect – a quick
recap’. This slide is timed. When the last bullet
point appears, click for the next slide which once
again is timed, needing no teacher computer input.
| OPTIONAL
ICT ACTIVITY – DATALOGGING) -
Fill 3 round bottomed
flasks, one with methane (from the gas taps),
one with air and one with carbon dioxide.
Place a temperature probe into each round
bottomed flask and a light bulb next to each
flask. Then during the lesson leave the experiment
running, students may then use this information
to support their argument. |
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| Main
activity |
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is suggested that the material (the graphs/tables
and diagrams) are not provided to the students in
one go as this may be overwhelming. Rather, present
the materials bit by bit to allow the groups time
to decide to dismiss this as evidence for their
argument.
Guidance notes are provided for the teacher with
suggested evidence the students may use. These
may not be the only interpretations from the graphs,
but it’s a start!
If students finish before the 25 minutes, then
they could consider what evidence does not support
their argument and whether there is any other
evidence that they can gather to contradict this
(eg. graph 17 implies that the temperature change
is opposite to what scientists would expect, so
proving global warming, but graph 7 indicates
the opposite since 2000) and graph 10 shows that
if we look at millions of years then the GMST
is decreasing. |
| Plenary |
| Each group presents
their three statements (and certainly no more than
6). This means that the students should be encouraged
to decide which are their most convincing pieces
of evidence and use only these. This is only intended
to be a 15 minute activity but you may decide to
set this up for a debate in the following lesson
for which you might ask students to consider also
what evidence there is that does not support their
argument, and how this may be discredited, or why
they have ignored it. |
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Group
1: - ENVIRONMENTAL GROUP (GREENPEACE)
You believe that the Kyoto agreement is essential
for the future of this planet and the threat
that Earth could be the next Venus is a reality.
You believe that the government need to find
ways to reduce Co2 emissions as this is the
major cause of climate change. You must use
the data available to argue (make a conclusion)
that you are correct and that there is no
other explanation for the climate changes:
that the government must be held accountable
for this very ‘real’ problem. |
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| Possible evidence: |
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Table
1 – the concentration
of greenhouse gases in the atmosphere has
risen dramatically |
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Table
2 – the man-made
additions of CO2
was approximately a 1/6th of the naturally
occurring CO2
levels. With very high atmospheric lifetime. |
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Table
3 – The greenhouse
effect is caused by CO2
as this is the gas that is clearly present
in the greatest concentration on Venus and
the greenhouse effect definitely occurs on
Venus. |
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Graph
1 – the projected
increase in sea level is 0.9m by 2100 – demonstrating
that global warming does have an effect on
the climate. Graph 19 confirms an increase
in sea levels (but not as dramatic?) |
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Graph
2-6 – shows a general
increase in global temperature during last
century, this is confirmed graph 9 and graph
7, as although there are fluctuations and
seems to show a decrease beginning just before
2000 there is has yet to decrease to a 0 degree
C change in temperature. |
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Graph
11 – shows a direct
correlation between CO2
levels and global temperature, the fluctuations
are the same (the two lines mirror each other) |
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Graph 12-14
– shows a dramatic increase in the concentrations
of the greenhouse gases. |
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Graph 15
– confirms the increase of CO2
in the atmosphere from 1958. |
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Graph 16
– the world is getting warmer. |
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Graph
17 – that, if their
was no human impact upon the Earth, scientists
would be predicting that global temperatures
would be decreasing but the opposite is occurring. |
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Diagram 1 – The
amount of sea ice has reduced since 1979. |
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Suggested
Conclusions (Students must choose the graphs
to support this argument):
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The graphs clearly
demonstrate an increase in CO2
levels and a corresponding alteration in global
temperatures. |
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Global warming
does exist; there is a projected increase
in sea levels based on observations, including
the decrease in sea ice. |
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The world is getting
warmer but it is predicted that the Earth
should be decreasing. |
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| These
arguments may also be used for Group 4 |
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Group
2: MEMBER OF PUBLIC
You are concerned by rising petrol prices
and increased household energy bills. You
don’t truly understand the reasons behind
the Kyoto agreement. You must use the data
to present a balanced argument as to whether
Earth is really going to become the next Venus
and whether these increases are justified. |
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| This Group can choose
to use any argument provided in any of these answer
sheets. |
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Group
3 – MEMBER OF PARLIAMENT
You are a member of the current Western government
and believe that you are being unfairly penalised
for your growing industrial economy. You have
no problem with looking at alternative energy
sources (reducing fossil fuel emissions) but
believe that you are not a major contributor
to climate change and in fact would argue
that global warming does not exist and that
the current and projected climate changes
are a natural cycle of the Earth. You believe
that the threat that Earth is the next Venus
is unjustified. You must use the data available
to argue (make a conclusion) that the Kyoto
agreement is unfair to the industrialised
Western world, especially when the Eastern
world economy relies on its production of
rice in paddy fields and is not necessarily
being penalised equally for this. |
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Possible
evidence:
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Table
1 – the % change
in methane is a lot greater than the increase
in manmade carbon dioxide, so you are been
unfairly penalised as paddy fields produce
the methane, not you. |
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Table
3 – the concentration
of CO2
in Venus’ atmosphere is 213333 times greater
than Earth, so Earth will never reach this
level, it can’t be a Venus. |
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Graph
7 – shows that the
global temperature is beginning to decrease. |
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Graph
10 – That on a
larger time range the global temperature is
following a pattern and actually decreasing
and that maybe we could expect a dramatic
decrease in GMST and therefore regardless
of human activity earth has a natural cycle
in temperatures. |
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Graph
11 – That the temperature
change in the Earth may not be related to
CO2
concentration but that it also mimics the
change in methane concentrations. |
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Possible
conclusions (must be supported by graphs/table no’s)
see brief;
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That
methane is the major contributor to global
warming not CO2 |
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That fluctuations
in Earth’s temperature are a naturally occurring
phenomena and that the Kyoto agreement will
not have any effect. |
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That the
concentration of CO2
is nothing like Venus, so there is no evidence
that the concentration on Earth can produce
global warming. |
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| These
arguments may also be used for Group 5 |
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| References |
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| Tables |
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| Graphs |
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| Diagrams |
| Diagram 1
ACIA, Impacts
of a Warming Arctic, Arctic
Climate Impact Assessment, 2004 |
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| http://www.ucsusa.org/global_warming/science/arctic-climate-impact-assessment.html |
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