Now that we have presented techniques that allow us to conduct more precise analyses, we’ll return to case 3.1. Recall that there are two issues in this discussion. First, is there global warming and, second, if so, is carbon dioxide the cause? The only tools available at the end of chapter 3 were graphical techniques including line charts and scatter diagrams.
You are now invited to apply the more precise techniques used in this chapter to answer the same questions. Here are the data sets you can work with:
C04-01a: Column 1: Months numbered 1 to 1597
Column 2: Temperature anomalies produced by the National climatic Data center
C04-01b: Column 1: Year Column 2: Month Column 3: monthly carbon dioxide levels measured by the Mauna Loa observatory
Column 4: Temperature anomalies produced by the National climatic Data center
a. Use the least squares method to estimate average monthly changes in temperature anomalies.
b. Calculate the least squares line and the coefficient of correlation between CO2 levels and temperature anomalies and describe your findings.