Figure 3:Changing concentrations of carbon dioxide in the atmosphere over the past 1000 years. The measurements are taken from four Antarctic ice cores and are combined with those from Mauna Loa, Hawaii. Note the rapid increase since about 1850. (Source: IPCC)

Changing concentrations of carbon dioxide in the atmosphere over the past 1000 years. The measurements are taken from four Antarctic ice cores and are combined with those from Mauna Loa, Hawaii. Note the rapid increase since about 1850. (Source: IPCC)

Similar data from a single site in Antarctica (Law Dome):