GGGG - Energy and Climate, Global Warming Film
Alternatives to fossil-fuel derived energy are nuclear power and renewable energy.
a) (4 pts) Name and briefly explain two drawbacks associated with relying on nuclear power as an energy source in the decades to come.
b) (4 pts) Name and briefly explain two drawbacks associated with relying on renewable energy sources in the decades to come.
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Many scientists believe that the Earth will suffer varying degrees of global warming in the next 100 years or so because of increasing levels of carbon dioxide in our atmosphere.
a) (5 pts) Explain the evidence that confirms the buildup of carbon dioxide in our atmosphere is caused by human rather than natural activity.
b) (3 pts) In the very distant past, the Earth had much more carbon dioxide in our atmosphere than it does now, yet the temperature on the Earth was about the same as it is today. Explain why.
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Since global warming is a major concern in the decades to come, many scientists are advocating the introduction of nuclear power as a Carbon-free alternative.
a) (6 pts) Name and briefly explain two drawbacks associated with nuclear power as an energy source for the future.
b) (3 pts) One possible way to extend the lifetime of nuclear power as an energy source would be to use breeder reactors. What is a potential problem with this approach?
c) (5 pts) If global warming does occur, sea levels will rise due to melting ice caps in Antarctica. Name and briefly explain one other reason sea levels would rise.
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As Carbon Dioxide abundances in our atmosphere have increased over the past two centuries, the relative abundances of Carbon-14 and Carbon-12 have changed significantly.
a) (7 pts) Explain how this evidence leads scientists to believe that the source of the increased carbon in the atmosphere is due to fossil fuel burning rather than natural sources like volcanism.
b) (7 pts) In our atmosphere, molecules with Carbon-12 tend to move around a bit faster than molecules with Carbon-14. Explain why (note that merely stating a relationship between mass and velocity is *not* sufficient...it must be explained).
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Scientists have been trying to decades to model the past history of the Earth's climate so that they can predict future changes with greater confidence. One important ingredient in these models is a record of past climatic changes on the Earth.
a) (4 pts) Given an example of an experiment that indicates the average temperature on the Earth during times before written records were kept. Explain.
b) (4 pts) Climatic models attempt to predict changes in the weather in the near future. Explain the most significant reason that these models have such a wide range of future predictions.
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Aside from increased ice melting on the Earth's surface, the greenhouse effect may result in dramatic sea level rises due to another reason. Describe this (most important of all other possible reasons) briefly.
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Scientists have been studying the past history of Earth's climate for decades in an attempt to unravel the mystery of global warming.
a) (6 pts) Describe an experiment that can indicate the temperature at a particular region on the Earth hundreds or thousands of years ago, some measurement not based on a written record. Describe what result would indicate high temperature as opposed to lower temperature.
b) (8 pts) Climatic models that attempt to predict changes in the weather have real problems estimating the effects of positive and negative feedback in the global warming cycle. Describe one example of each kind of feedback.
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Recently, many world governments attempted to ratify and enforce a carbon emissions treaty negotiated in Kyoto, Japan. In the United States, the Senate voted 95-0 in opposition to this treaty.
a) (6 pts) Briefly explain why climate scientists were "underwhelmed" by the Kyoto treaty, thinking it wasn't a very good plan. Also explain why politicians in the US and other developed nations were opposed to the treaty.
b) (8 pts) One way to replace Carbon-based energy would be with solar power. Explain how photovoltaic cells convert sunlight into usable energy, then explain how the solar II project can produce energy even when the sun isn't shining.
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Although "cold fusion" appears to be a dead end path, many scientists think conventional high temperature fusion holds some promise to solving Earth's energy demands.
a) (8 pts) Explain how the "cold fusion" (fusion at room temperature) process supposedly was able to overcome the natural electric repulsion between Hydrogen nuclei to enable fusion to take place, then give one reason why most scientists don't believe that this process works.
b) (6 pts) Briefly explain two different types of high temperature fusion experiments that may someday be able to provide the world's power on large scales.
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What are two types of renewable energy sources? Name and explain two drawbacks commonly associated with renewable energy source.
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This question deals with two issues involving global warming, which we discussed extensively this semester.
a) (4 pts) Explain the evidence that tells us the increasing level of Carbon Dioxide in the atmosphere is largely due to human (not natural) activity.
b) (4 pts) Explain the mechanism (besides melting ice in the Antarctic) that may cause sea levels to dramatically rise as a result of warming over the next 100 years or so.
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Nuclear energy was also discussed as an alternative to fossil fuel burning.
a) (6 pts) Name and briefly explain two problems associated with nuclear energy and why it is not as easily viable as fossil fuel energy.
b) (8 pts) Rather than fission energy, some scientists have looked into very high temperature controlled fusion energy. Two different kinds of fusion reactions are inertially and magnetically confined. Describe how each works.
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Since global warming is a major concern in the decades to come, many scientists are advocating the introduction of nuclear power as a Carbon-free alternative.
a) (6 pts) Name and briefly explain two drawbacks associated with nuclear power as an energy source for the future.
b) (3 pts) One possible way to extend the lifetime of nuclear power as an energy source would be to use breeder reactors. What is a potential problem with this approach?
c) (5 pts) If global warming does occur, sea levels will rise due to melting ice caps in Antarctica. Name and briefly explain one other reason sea levels would rise.
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A potential solution to our energy needs may come with the development of nuclear fusion technology, but this requires using plasma and very high temperatures, something we haven't been able to do very efficiently.
a) (3 pts) Explain what plasma is.
b) (5 pts) Explain why fusion reactions require such high temperatures.