Concept explainers
Use the following questions to check your understanding of some of the many types of visual information used in astronomy. For additional practice, try the Chapter 10 Visual Quiz at Mastering Astronomy.
The graph above, a portion of Figure 10.39, shows the atmospheric concentration of carbon dioxide for the past 800,000 years. Use the information in the graph to answer the following questions.
5. Which of the following best describes the relationship between the graph of global average temperatures and the graph of CO2 levels? (Focus on the period since about 1960.)
a. The warmest year correlate exactly with the years of greatest CO2 abundance, indicating that CO2 is the single most important factor controlling global temperature changes.
b. The warmest years correlate roughly with the years of greatest CO2 abundance, indicating that CO2 is important but other factors also contribute to global temperature changes.
c. The warmest years are not correlated with year of high CO2 abundance, indicating that factors of the than CO2 have the most important effect on global temperature changes.
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The Cosmic Perspective (8th Edition)
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