Geoscience Reference
In-Depth Information
Figure 25.3. Changing concentrations of carbon dioxide and methane from air
bubbles trapped in Antarctic ice during the past 150,000 years. (From Williams,
2001a
, fig.1.8.)
Table 25.1.
Summary of key greenhouse gases affected by human
activities. (From IPCC,
2007a
, and Houghton,
2009
; ppmv is parts
per million by volume; ppbv is parts per billion by volume.)
Carbon dioxide
(ppmv)
Methane
(ppbv)
Nitrous oxide
(ppbv)
Pre-industrial concentration
280
715
270
Concentration in 2005
379
1774
319
Atmospheric lifetime (years)
50-200
12
114
