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Evidence of changing concentrations of atmospheric CO2, N2O and CH4 from air bubbles in Antarctic ice

Abstract

Atmospheric carbon dioxide (CO2) levels before the industrial revolution were 260–280 p.p.m.v. (parts per 106 by volume) as determined from studies of air trapped in ice1,2. We report here similar results, using Antarctic ice, for the CO2 levels during the seventeenth and eighteenth centuries, which suggest an average concentration of 281 (standard deviation σ = 7) p.p.m.v. The data constrain the net release of biospheric carbon to the atmosphere over the past 200 yr, to 5 × 1010 tonnes of carbon, mostly during 1850–1900. Measurements of two other ‘greenhouse’ gases, methane (CH4) and nitrous oxide (N2O), show increases of about 90 and 8% respectively since 1600. This CH4 increase is similar to the recently reported3–6 doubling over the same period, and the N2O increase, the first direct evidence of historical changes in N2O, is consistent with releases due to expanding anthropogenic combustion processes7.

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References

  1. 1

    Neftel, A., Moor, E., Oeschger, H. & Stauffer, B. Nature 315, 45–47 (1985).

  2. 2

    Raynaud, D. & Barnola, J. M. Nature 315, 309–311 (1985).

  3. 3

    Khalil, M. A. K. & Rasmussen, R. A. Chemosphere 11, 877–883 (1982).

  4. 4

    Craig, H. & Chou, C. C. Geophys. Res. Lett. 9, 1221–1224 (1982).

  5. 5

    Rasmussen, R. A. & Khalil, M. A. K. J. geophys. Res. 89, 11599–11605 (1984).

  6. 6

    Stauffer, B., Fischer, G., Neftel, A. & Oescher, H. Science 229, 1386–1388 (1985).

  7. 7

    Weiss, R. F. J. geophys. Res. 86, 7185–7195 (1981).

  8. 8

    Morgan, V. I. Climat. Change 7, 415–419 (1985).

  9. 9

    Schwander, J. & Stauffer, B. Nature 311, 45–47 (1984).

  10. 10

    Khalil, M. A. K. & Rasmussen, R. A. Tellus 35B, 161–169 (1983).

  11. 11

    Khalil, M. A. K. & Rasmussen, R. A. Atmos. Envir. 19, 397–407 (1985).

  12. 12

    Pearman, G. I. Search 15, 42–45 (1984).

  13. 13

    Enting, I. G. & Pearman, G. I. Proc. 6th ORNL Life Sci. Symp. The Global Carbon Cycle, Knoxville, Tennessee,(in the press).

  14. 14

    Fraser, P. J. et al. in Baseline 1983–84 (eds Francey, R. J. & Forgan, B.) (Australian Department of Science and Technology, in the press).

  15. 15

    Rasmuseen, R. A. & Lovelock, J. E. J. geophys. Res. 88, 8369–8378 (1983).

  16. 16

    Fraser, P. J., Khalil, M. A. K., Rasmussen, R. A. & Steele, L. P. J. atmos. Chem. 1, 125–135 (1984).

  17. 17

    Fraser, P. J., Hyson, P., Rasmussen, R. A., Crawford, A. J. & Khalil, M. A. K. J. atmos. Chem. (in the press).

  18. 18

    Rasmussen, R. A. & Khalil, M. A. K. J geophys. Res. 86, 9826–9832 (1981).

  19. 19

    Keeling, C. D. in Numeric data package NDPOQl (Carbon Dioxide Information Centre, Oak Ridge, Tennessee, 1984).

  20. 20

    Pearman, G. I. & Beardsmore, D. J. Tellus 36B, 1–24 (1984).

  21. 21

    Rotty, R. M. J. geophys. Res. 88, 1301–1308 (1983).

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