According to an August 2011 report from the government research laboratory known as NOAA-ESRL, the amount of carbon dioxide in Earth's atmosphere increased by almost 25% (from 315 ppm to 392 ppm) between 1958 and 2011. The graph below illustrates this increase as well as the yearly cycle, which is driven by the seasons.

Question

Image courtesy of NOAA
A scientist wants to study how this change in carbon dioxide in Earth's atmosphere is correlated with temperature change on Earth. It would be best for the scientist to compare the data in the graph above to which of the following?
A.
a graph showing the annual average global temperatures for 1958 through 2011
B.
a graph showing the annual low temperatures in one city for 1958 through 2011
C.
a table showing the average high and low temperatures in various cities in 1958
D.
a table showing the average high and low temperatures in various cities in 2011

Answer 1

To study how the change in carbon dioxide levels in Earth's atmosphere correlates with temperature change on Earth, it would be best for the scientist to compare the data in the graph to:

A. a graph showing the annual average global temperatures for 1958 through 2011.

This option provides a comprehensive overview of temperature changes on a global scale over the same time period as the carbon dioxide data, allowing for a more direct comparison of trends and correlations between atmospheric CO2 levels and global temperatures. Options B, C, and D focus on individual cities or only specific years, which would not provide a suitable context for understanding broad global patterns.