Figure 10: Variations in
atmospheric CO2 concentration on different time-scales. (a) Direct
measurements of atmospheric CO2. (b) CO2 concentration in
Antarctic ice cores for the past millenium. Recent atmospheric measurements (Mauna
Loa) are shown for comparison. (c) CO2 concentration in the Taylor
Dome Antarctic ice core. (d) CO2 concentration in the Vostok Antarctic
ice core. (Different colours represent results from different studies.) (e to
f) Geochemically inferred CO2 concentrations. (Coloured bars and lines
represent different published studies) (g) Annual atmospheric increases in CO2.
Monthly atmospheric increases have been filtered to remove the seasonal cycle.
Vertical arrows denote El Niño events. A horizontal line defines the extended
El Niño of 1991 to 1994. [Based on Figures 3.2