Paleoclimate a History of Change Answer Key

Click and Learn Paleoclimate: A History of Change Student Worksheet ABOUT THIS WORKSHEET Students will examine and analyze factors controlling Earth’s climate and describe human impact on climate change. Students will describe methods to mitigate impacts of climate change. PROCEDURE Use the Paleoclimate: A History of Change Click & Learn to answer the following questions. Please bold or type your answers in red. 1. List three greenhouse gases: Carbon dioxide, Methane, Water Vapor 2. Which is the most important of these gases in terms of amplification of climate effects? Water vapor because it turns over quickly and it lasts in the atmosphere for hours, days, and weeks. 3. Describe how these gases act like a “thermal blanket.” They absorb radiation and re-radiate it both back to space and downward, which is how it acts like a thermal blanket. “The story of Earth’s climate has been a story of massive changes. Earth has been much warmer and much colder than it is today, including times when there were no ice caps and times when the entire planet was nearly frozen over.” 4. Based on this statement, should changes in Earth’s climate cause anxiety? If you answer yes, please support your opinion with factual information. If you answer no, please explain why we should not worry. Yes, because the changes are occurring as the chemical composition of the atmosphere has changed over time varying the strength of the greenhouse effect, which causes variance in the amount of variation. This means that the planet is forever changing, and we should always keep a close watch on Earth. 5. What are the main factors that affect Earth’s climate? When CO2 rises, then temperatures rise. 6. We know from the relative amounts of 16O and 18O that global temperatures and global climate have changed over time. Why is it important for scientists to be able to explain how they know that climate has changed over time and that they are able to repeat experiments that support this information? So, they can understand the extent of change in global temperatures and climates and be able to lessen it. 7. Atmospheric changes in Earth’s history have caused large temperature changes through time. Explain how knowledge of these past connections between atmosphere and climate can inform us about modern-day climate change. These connections tell us that because the climate changed due to an increase of Co2 in the atmosphere are due to agricultural and industrial change caused by humans, therefore we should take measure to reduce the amount of carbon we use. 8. Explain how the ability to describe the pattern of ice ages over the past million years helps us to assess what is a “normal” variation in Earth’s atmosphere. The graph shows that ice caps have melted over the past millions of years and what is too hot and cold for the Earth’s atmosphere. 9. Changes in atmosphere are not the only changes that impact climate. How can changes in Earth’s orbit impact temperature? Small changes in Earth’s orbit around the sun affect the amount and distribution of solar energy striking the planet. 10. Describe how small changes in Earth’s orbit around the sun explain the pattern of glacial and interglacial periods over the past million years. When the orbit is more elliptical, glaciation is affected by the time of year (season) that Earth is closest to the sun. 11. Based on the information you have just learned, please explain how Milankovitch cycles can be used to predict future changes in Earth’s climate. The closer the Earth is to the sun, the warmer the climate. 12. Using the chart titled CO2 and Temperature Fluctuations During the Past 800,000 Years: a. describe the fluctuations in CO2 and temperature over the past 800,000 years, and explain why you see oscillations. There is a rise in CO2 since humans are using a lot of it for agriculture and industry. b. explain the cause for the significant changes seen at 0 years before present on the CO2 and Temperature Fluctuations During the Past 800,000 Years chart. The increasing rise in Co2 emissions because of human activities. 13. What is the big concern about the rate of CO2 change in Earth’s climate? It is getting warmer at geologically unusual rates, rate of change is rapid in the environment. 14. Using the information provided for the past 800,000 years: a. estimate the length of time that it took for CO 2 to go from 200 to 300 ppm. 17000 years b. estimate the length of time that it took for CO 2 to go from 300 to 400 ppm. 100 years c. Compare the rate of change from 300 ppm to 400 ppm to the rate of change from 200 to 300 ppm. 16000 years 15. What has happened in the past 150 years that has caused this rise in the rate at which CO 2 is added to the atmosphere? Industrial revolution. 16. List five potentially severe impacts of rapid climate change: 1._________droughts_ 3._________floods______________ 5._____sea level rise _______________ 2._________heat 4._____________storms __________ waves____________ 17. Explain the importance of educating others about climate change consequences. Describe how you would present the information in a way that would cover the most important points, as well as emphasizing that changes in human behavior can make a difference in the ultimate impacts of climate change. Educating others about climate change would bring about changes in how humans currently live, there would be initiatives to reduce the amount of Co2 in the atmosphere, lower the burning of fossil fuels and much more. In order to cause a difference, I would present the information about climate change through the media in order to reach as many people as possible.