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Atmospheric Concentrations of Greenhouse Gases in Geological Time and in Recent Years

Figure 1 - Carbon Dioxide | Figure 2 - Methane | Figure 3 - Nitrous Oxide

Figure 1: Atmospheric Concentrations of Carbon Dioxide in Geologic Time and in Recent Years

Figure 1: Atmospheric Concentrations of Carbon Dioxide in Geologic Time and in Recent Years: This diagram is in three sections. The first, using data from ice cores in Antarctica, shows CO2 concentrations from 647,426 B.C. to 337 B.C., with a clear cyclical pattern of peaks and valleys. The second, using data from other Antarctic ice cores, shows CO2 concentrations from 8947 B.C. to 1975 A.D. The diagram shows a slight upward trend in concentrations until the 20th century, when they shoot up rapidly. The third section, using data from CO2 monitoring stations around the world, shows CO2 concentrations from 1959 to 2006. The trend shows a steady increase in concentrations from about 320 ppm in 1959 to approximately 380 ppm in 2006.

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Figure 2: Atmospheric Concentrations of Methane in Geologic Time and in Recent Years

Figure 2: Atmospheric Concentrations of Methane in Geologic Time and in Recent Years: This diagram is in three sections. The first, using data from ice cores in Antarctica and Greenland, shows methane concentrations from 648,679 B.C. to 346 B.C. Concentrations during the period vary widely, from as high as 800 ppb to as low as less than 100 ppb. The second, using data from other ice cores, shows methane concentrations from 8945 B.C. to 1980 A.D. The diagram shows a relatively flat trend in concentrations until the 20th century, when they shoot up rapidly. The third section, using data from several atmospheric monitoring stations around the world, shows methane concentrations from 1985 to 2001. The trend shows an increase in concentrations during most of the period, with an apparent leveling off in the later years.

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Figure 3: Atmospheric Concentrations of Nitrous Oxide in Geologic Time and in Recent Years

Figure 3: Atmospheric Concentrations of Nitrous Oxide in Geologic Time and in Recent Years: This diagram is in three sections. The first, using data from ice cores in East Antarctica and Greenland, shows nitrous oxide concentrations from 104,301 B.C. to 1871 A.D. Concentrations during the period varied widely, ranging from 180 ppb to more than 280 ppb, with an upward trend toward the end of the period. The second, using data from a variety of sources, shows nitrous oxide concentrations from 9000 B.C. to 1976 A.D. The diagram shows a relatively flat trend in concentrations until the 20th century, when they shoot up rapidly. The third section, using data from several atmospheric monitoring stations around the world, shows nitrous oxide concentrations from 1977 to 2005. The trend shows a steady increase in concentrations, rising from around 300 ppb in 1997 to 320 ppb in 2005.

Full references are available at the bottom of this page.

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References

CO2
CH4
N2O

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