Comparing two datasets. The first dataset comes from World Data Center for Paleoclimatology, Boulder, and NOAA Paleoclimatology Program and describes the carbon dioxide levels back thousands of years “Before Present” (BP) or before January 1, 1950. The second dataset explores carbon dioxide starting at year zero up until the recent year 2014. This dataset was compiled by the Institute for Atmospheric and Climate Science (IAC) at Eidgenössische Technische Hochschule in Zürich, Switzerland.