The Last 40 Years
The accompanying figure depicts atmospheric CO2 concentrations from 1958 to the present as measured at Mauna Loa, Hawaii. These data, obtained by Keeling and Whorf (1998), represent the longest continuous record of directly measured CO2 concentrations. As the graph of these data indicates, there has been a substantial and sustained rise in the air's CO2 content over the past four decades.
The accompanying figure depicts atmospheric CO2 concentrations from 1958 to the present as measured at Mauna Loa, Hawaii. These data, obtained by Keeling and Whorf (1998), represent the longest continuous record of directly measured CO2 concentrations. As the graph of these data indicates, there has been a substantial and sustained rise in the air's CO2 content over the past four decades.
To access a file of the data from which the graph was constructed, click here.
Reference
Keeling, C.D. and Whorf, T.P. 1998. Atmospheric CO2 concentrations -- Mauna Loa Observatory, Hawaii, 1958-1997 (revised August 2000). NDP-001. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, Oak Ridge, Tennessee.