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Natural and anthropogenic variations in methane sources during the past two millennia

Abstract

Methane is an important greenhouse gas that is emitted from multiple natural and anthropogenic sources. Atmospheric methane concentrations have varied on a number of timescales in the past, but what has caused these variations is not always well understood1,2,3,4,5,6,7,8. The different sources and sinks of methane have specific isotopic signatures, and the isotopic composition of methane can therefore help to identify the environmental drivers of variations in atmospheric methane concentrations9. Here we present high-resolution carbon isotope data (δ13C content) for methane from two ice cores from Greenland for the past two millennia. We find that the δ13C content underwent pronounced centennial-scale variations between 100 bc and ad 1600. With the help of two-box model calculations, we show that the centennial-scale variations in isotope ratios can be attributed to changes in pyrogenic and biogenic sources. We find correlations between these source changes and both natural climate variability—such as the Medieval Climate Anomaly and the Little Ice Age—and changes in human population and land use, such as the decline of the Roman empire and the Han dynasty, and the population expansion during the medieval period.

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Figure 1: Records of δ 13 C and mixing ratio of CH 4 over the past two millennia.
Figure 2: Reconstructed scenarios for pyrogenic and biogenic CH 4 emissions and other palaeoproxies between 100 bc and ad 1600.
Figure 3: Comparison between estimate of area under land use and CH 4 mixing ratio.

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References

  1. Ferretti, D. et al. Unexpected changes to the global methane budget over the past 2000 years. Science 309, 1714–1717 (2005)

    Article  ADS  CAS  Google Scholar 

  2. Mischler, J. A. et al. Carbon and hydrogen isotopic composition of methane over the last 1000 years. Glob. Biogeochem. Cycles. 23, GB4024, http://dx.doi.org/10.1029/2009GB003460 (2009)

    Article  ADS  Google Scholar 

  3. Houweling, S. et al. Early anthropogenic CH4 emissions and the variation of CH4 and 13CH4 over the last millennium. Glob. Biogeochem.. Cycles 22(1), http://dx.doi.org/10.1029/2007GB002961 (2008)

  4. MacFarling Meure, C. et al. Law Dome CO2, CH4 and N2O ice core records extended to 2000 years BP. Geophys. Res. Lett. 33, L14810 http://dx.doi.org/10.1029/2006GL026152 (2006)

    Article  ADS  Google Scholar 

  5. Blunier, T. et al. Variations in atmospheric methane concentration during the Holocene epoch. Nature 374, 46–49 (1995)

    Article  ADS  CAS  Google Scholar 

  6. Chappellaz, J. et al. Changes in atmospheric CH4 gradient between Greenland and Antarctica during Holocene. J. Geophys. Res. 102 (D13). 15987–15997 (1997)

    Article  ADS  CAS  Google Scholar 

  7. Mitchell, L. E. et al. Multidecadal variability of atmospheric methane, 1000–1800 CE. J. Geophys. Res. 116, G02007, http://dx.doi.org/10.1029/2010JG001441 (2011)

    Article  ADS  Google Scholar 

  8. Singarayer, J. S. et al. Late Holocene methane rise caused by orbitally controlled increase in tropical sources. Nature 470, 82–85 (2011)

    Article  ADS  CAS  Google Scholar 

  9. Quay, P. et al. The isotopic composition of atmospheric methane. Glob. Biogeochem. Cycles 13, 445–461 (1999)

    Article  ADS  CAS  Google Scholar 

  10. Etiope, G., Lassey, K. R., Klusman, R. W. & Boschi, E. Reappraisal of the fossil methane budget and related emission from geologic sources. Geophys. Res. Lett. 35, L09307, http://dx.doi.org/10.1029/2008GL033623 (2008)

    Article  ADS  Google Scholar 

  11. Marlon, J. R. et al. Climate and human influences on global biomass burning over the past two millennia. Nature Geosci. 1, 697–702 (2008)

    Article  ADS  CAS  Google Scholar 

  12. Pechony, O. & Shindell, D. T. Driving forces of global wildfires over the past millennium and the forthcoming century. Proc. Natl Acad. Sci. USA 107, 19167–19170 (2010)

    Article  ADS  CAS  Google Scholar 

  13. Kaplan, J. O. et al. Holocene carbon emissions as a result of anthropogenic land cover change. Holocene 21, 775–791 (2011)

    Article  ADS  Google Scholar 

  14. Schmidt, G. A. et al. Climate forcing reconstructions for use in PMIP simulations of the last millennium (v1.1). Geosci. Model Dev. 5, 185–191 (2012)

    Article  ADS  Google Scholar 

  15. Helama, S., Merilainen, J. & Tuomenvirta, H. Multicentennial megadrought in northern Europe coincided with a global El Nino-Southern Oscillation drought pattern during the Medieval Climate Anomaly. Geology 37, 175 (2009)

    Article  ADS  Google Scholar 

  16. Moberg, A. et al. Highly variable Northern Hemisphere temperatures reconstructed from low- and high-resolution proxy data. Nature 433, 613–617 (2005)

    Article  ADS  CAS  Google Scholar 

  17. Ljungqvist, F. C. A new reconstruction of temperature variability in the extra-tropical northern hemisphere during the last two millennia. Geogr. Annal. A 92, 339–351 (2010)

    Article  Google Scholar 

  18. Hong, S. M., Candelone, J. P., Patterson, C. C. & Boutron, C. F. History of ancient copper smelting pollution during Roman and medieval times recorded in Greenland ice. Science 272, 246–249 (1996)

    Article  ADS  CAS  Google Scholar 

  19. Brännvall, M. L. et al. The Medieval metal industry was the cradle of modern large scale atmospheric lead pollution in northern Europe. Environ. Sci. Technol. 33, 4391–4395 (1999)

    Article  ADS  Google Scholar 

  20. Akagi, S. K. et al. Emission factors for open and domestic biomass burning for use in atmospheric models. Atmos. Chem. Phys. 11, 4039–4072 (2011)

    Article  ADS  CAS  Google Scholar 

  21. Craddock, P. T. Handbook of Engineering and Technology in the Classical World Ch. 4 98–120 (Oxford Univ. Press, 2008)

    Google Scholar 

  22. Ringeval, B. et al. Climate-CH4 feedback from wetlands and its interaction with the climate-CO2 feedback. Biogeosciences 8, 2137–2157 (2011)

    Article  ADS  CAS  Google Scholar 

  23. Sowers, T. Atmospheric methane isotope records covering the Holocene period. Quat. Sci. Rev. 29, 213–221 (2010)

    Article  ADS  Google Scholar 

  24. Ruddiman, W. F. & Thomson, J. S. The case for human causes of increased atmospheric CH4 . Quat. Sci. Rev. 20, 1769–1777 (2001)

    Article  ADS  Google Scholar 

  25. Burns, S. J. Speleothem records of changes in tropical hydrology over the Holocene and possible implications for atmospheric methane. Holocene 21, 735–741 (2011)

    Article  ADS  Google Scholar 

  26. Fuller, D. Q. et al. The contribution of rice agriculture and livestock pastoralism to prehistoric methane levels: an archaeological assessment. Holocene 21, 743–759 (2011)

    Article  ADS  Google Scholar 

  27. Sapart, C. J. et al. Simultaneous stable isotope analysis of methane and nitrous oxide on ice core samples. Atmos. Meas. Tech. 4, 2607–2618 (2011)

    Article  CAS  Google Scholar 

  28. Sapart, C. J. et al. Reconstruction of the carbon isotopic composition of methane over the last 50 yr based on firn air measurements at 11 polar sites. Atmos. Chem. Phys. Discuss. 12, 9587–9619 (2012)

    Article  ADS  Google Scholar 

  29. Buizert, C. et al. Gas transport in firn: multiple-tracer characterisation and model intercomparison for NEEM, Northern Greenland. Atmos. Chem. Phys. Discuss. 11, 15975–16021 (2011)

    Article  ADS  Google Scholar 

  30. Schwander, J. et al. The age of the air in the firn and the ice at Summit, Greenland. J. Geophys. Res. 98 (D2). 2831–2838 (1993)

    Article  ADS  CAS  Google Scholar 

Download references

Acknowledgements

We thank M. Bigler for sharing NEEM CFA dust and ion data; the NEEM community for providing us with ice core samples; and O. Pechony, J. Marlon and Z. Wang for sharing data on fire activity and the charcoal index. This project was supported by the Dutch Science Foundation (NOW; projects 851.30.020 and 865.07.001). NEEM is directed and organized by the Center of Ice and Climate at the Niels Bohr Institute and the US NSF, Office of Polar Programs; it is supported by funding agencies and institutions in Belgium (FNRS-CFB and FWO), Canada (NRCan/GSC), China (CAS), Denmark (FIST), France (IPEV, CNRS/INSU, CEA and ANR), Germany (AWI), Iceland (RannIs), Japan (NIPR), Korea (KOPRI), The Netherlands (NWO/ALW), Sweden (VR), Switzerland (SNF), the UK (NERC) and the USA (US NSF, Office of Polar Programs, ARC 0806407). J.O.K. and K.M.K. were supported by the Swiss National Science Foundation (grant PP0022_119049) and FIRB project CASTANEA (RBID08LNFJ).

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C.J.S, T.R, R.S.W.v.d.W., J.O.K. and G.M wrote the manuscript. T.R. and R.S.W.v.d.W. planned and designed the study. C.J.S, T.R., R.S.W.v.d.W., J.O.K., G.M., S.H., M.C.K., K.M.K., P.S., T.S., M.P. and T.B. worked on the scientific interpretation. C.J.S., M.P and C.v.d.V carried out the measurements. G.M., C.J.S., S.H., P.M. and E.W. carried out the modelling work. J.O.K. and K.M.K. provided reconstructions of human land use. D.D.-J. and T.B. led and coordinated the NEEM ice core drilling project and gas consortium.

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Correspondence to C. J. Sapart.

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The authors declare no competing financial interests.

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This file contains Supplementary Text and Data 1-4, Supplementary References, Supplementary Tables 1 and 2 and Supplementary Figures 1-7. (PDF 1773 kb)

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Sapart, C., Monteil, G., Prokopiou, M. et al. Natural and anthropogenic variations in methane sources during the past two millennia. Nature 490, 85–88 (2012). https://doi.org/10.1038/nature11461

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