This is the famous “Keeling Curve,” a graph of the concentration of carbon dioxide (CO2) in the atmosphere on the Mauna Loa Volcano on Hawaii Island. The data come from one of the longest-running observational studies in climate science. The observations were initiated by Charles David Keeling in 1958 and are continuing until this day. The Keeling curve provides the most convincing evidence to date of anthropogenic effects on the Earth’s climate.
Image: Wikipedia