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| Friday September 26, 2003 NOVA’s “What’s Up With the Weather?” Original broadcast April 18, 2000 From NOVA’s website: “NOVA investigates the complex scientific, ethical, and political issues surrounding possible human-induced global warming caused by the burning of fossil fuels. The program: * explains the natural greenhouse effect of Earth's atmosphere and its role in creating a habitable environment. * describes the link between burning fossil fuels and an increase in atmospheric carbon dioxide, the most important greenhouse gas. * examines the variety of methods by which scientists are attempting to reconstruct Earth's climate history and predict its future. * compares existing and potential human-induced change with known natural causes of climate change. * presents a wide range of outcomes from increasing atmospheric carbon dioxide. * quantifies the relationship between current and projected energy use and carbon emissions. * describes the growing global problem of fossil fuel use as developing nations become industrialized. * relates the difficulties surrounding recent international efforts to mitigate carbon dioxide emissions. * outlines the economic and political challenges associated with non-fossil energy sources and other possible solutions, such as carbon sequestration and improvements in energy.“ While watching the video, keep in mind the following questions: How much evidence do you need to convince yourself: that modern global temperatures are warming? that humans can have an effect on the planetary scale? that current climate is deviating from natural variability? that current global warming is due to humans? that climate change will endanger humans and biodiversity? that skeptics are raising valid points or just obfuscating the issue? And the associated value and policy questions: Does the U.S. have an obligation to reduce emissions? Should we act to avert possible disaster, or seek to react to changes when they occur? Is our trajectory of development unsustainable? What can individuals do about greenhouse gas emissions? LAB ASSIGNMENT: Answer the following questions based on watching the video. 1. What’s the difference between weather and climate? 2. Over the last century, global surface temperature has risen ______ degree Fahrenheit. 3. Why do some climate historians study records having to do with cherry blossoms? 4. Name 4 natural archives of climate change that tell us about places where humans weren’t keeping records over the last millennium. 5. A common argument by skeptics is that warming is natural and cyclic, like the Medieval Warm Period in the middle ages, where Greenland was inhabited by Vikings. What is the problem with this argument? 6. What did Charles David Keeling begin measuring in 1957? 7. What is the average surface temperature of the Earth? _______ degrees Farenheit 8. How long does carbon dioxide produced from burning fossil fuels remain in the atmosphere before being absorbed by the ocean? 9. Records from ice cores prove that although CO2 has been cyclic over periods of thousands of years, the current levels of CO2 are much higher than any time in the last ______________ years. 10. What arguments do the fossil fuel representatives use to assert that CO2 is not a pollutant? 11. What kind of study is being conducted to predict the effects of higher ambient CO2 on plant growth? 12. What is a complication with the argument that all our excess CO2 will be taken up by increased plant growth? 13. In climate models, what does Tom Wigley describe are 3 important factors that need to be added to the computer models? 14. What is the range of predicted temperature increase predicted by the models for a doubling of CO2? 15. Are oceans and feedbacks related to thermohaline circulation a large uncertainty? 16. Why is the argument over a doubling of CO2 somewhat irrelevant, in view of our predicted emissions? 17. Americans use ______ of the world’s energy 18. What percent of U.S. electricity is produced by burning coal?__________ percent 19. How many pounds of carbon is emitted per year by lighting an average house? 20. As a result of the Kyoto treaty, (A) Most developing nations agreed to cut back 20 percent in carbon dioxide emissions by 2020. (B) No nations agreed to cut carbon dioxide emissions. (C) Developing countries made no binding commitments to cut back carbon dioxide emissions. (D) Atmospheric carbon dioxide levels in the year 2100 will be about half of what they are today. 21. The total energy consumption of all humankind today is about _______ trillion watts. 22. How long is it projected that it will take before total world energy consumption reaches 40 trillion watts? 23. How many U.S. Senators voted against the Kyoto treaty? 24. Do you have any comments about the video and its portrayal of the climate debate? |