How are ice-core data and Mauna Loa atmospheric data made comparable?

 

An ice core extracted from the West Antarctica Ice Sheet
An ice core extracted from the West Antarctica Ice Sheet

Some readers of the Keeling Curve website have asked us about the graphs that show carbon dioxide concentrations since 1700 and over the past 800,000 years, which use a combination of data derived from analysis of the gas contained in ice cores and that obtained from air sampled at Mauna Loa Observatory in Hawaii. Continue reading How are ice-core data and Mauna Loa atmospheric data made comparable?