12. Are the decades with the highest and lowest average temperatures the same on both graphs? If not, how much do
they differ (i.e., how much time is there between them)?
13. On average have global temperatures risen or fallen since 1900, and how much have they
changed? Does the global data suggest that this trend will continue? Explain your answer.
14. How does the overall pattern in global temperature changes compare with changes in atmospheric CO2 levels?