OSA's Digital Library

Applied Optics

Applied Optics


  • Vol. 33, Iss. 33 — Nov. 20, 1994
  • pp: 7704–7716

High-precision direct measurements of 13CH4/12CH4 and 12CH3D/12CH4 ratios in atmospheric methane sources by means of a long-path tunable diode laser absorption spectrometer

Peter Bergamaschi, Michael Schupp, and Geoffrey W. Harris  »View Author Affiliations

Applied Optics, Vol. 33, Issue 33, pp. 7704-7716 (1994)

View Full Text Article

Enhanced HTML    Acrobat PDF (1583 KB)

Browse Journals / Lookup Meetings

Browse by Journal and Year


Lookup Conference Papers

Close Browse Journals / Lookup Meetings

Article Tools



Measurements of 13CH4/12CH4 and 12CH3D/12CH4 ratios in atmospheric methane (CH4) sources provide important information about the global CH4 budget as well as about CH4 production and consumption processes occurring within the various sources. As an alternative to the conventional mass spectrometer (MS) technique, which requires conversion of CH4 to CO2 and H2, we have developed a tunable diode laser absorption spectrometer (TDLAS), which permits rapid direct measurements of the 13CH4/12CH4 and 12CH3D/12CH4 ratios. An intercomparison between TDLAS and MS techniques for samples from natural wetlands, landfills, and natural gas sources resulted in a mean deviation of Δδ13C = 0.44‰ and ΔδD = 5.1‰. In the present system the minimum mixing ratios required are 50 parts in 106 by volume (ppmv) CH4 (sample size 2 μmol CH4) for direct δ13C measurements and 2000 ppmv (sample size 80 μmol CH4) for direct δD measurements. These mixing-ratio limits are adequate for most CH4 source characterization studies without requiring sample preconcentration.

© 1994 Optical Society of America

Original Manuscript: July 16, 1993
Revised Manuscript: January 19, 1994
Published: November 20, 1994

Peter Bergamaschi, Michael Schupp, and Geoffrey W. Harris, "High-precision direct measurements of 13CH4/12CH4 and 12CH3D/12CH4 ratios in atmospheric methane sources by means of a long-path tunable diode laser absorption spectrometer," Appl. Opt. 33, 7704-7716 (1994)

Sort:  Author  |  Year  |  Journal  |  Reset  


  1. R. A. Rasmussen, M. A. K. Khalil, “Atmospheric methane in the recent and ancient atmospheres: concentrations, trends, and interhemispheric gradient,” J. Geophys. Res. 89, 11599–11605 (1984). [CrossRef]
  2. D. R. Blake, F. S. Rowland, “Continuing worldwide increase in tropospheric methane, 1978 to 1987,” Science 239, 1129–1131 (1988). [CrossRef] [PubMed]
  3. D. M. Etheridge, G. I. Pearman, P. J. Fraser, “Changes in tropospheric methane between 1841 and 1978 from a high accumulation-rate Antarctic ice core,” Tellus 44, 282–294 (1992). [CrossRef]
  4. J. Lelieveld, P. J. Crutzen, C. Brühl, “Climate effects of atmospheric methane,” Chemosphere 26, 739–768 (1993). [CrossRef]
  5. R. J. Cicerone, R. S. Oremland, “Biogeochemical aspects of atmospheric methane,” Global Biogeochem. Cycles 2, 299–327 (1988). [CrossRef]
  6. C. M. Stevens, A. Engelkemeir, “Stable carbon isotopic composition of methane from natural and anthropogenic sources,” J. Geophys. Res. 93, 725–733 (1988). [CrossRef]
  7. M. Wahlen, N. Tanaka, R. Henry, B. Deck, J. Zeglen, J. S. Vogel, J. Southon, A. Shemesh, R. Fairbanks, W. Broecker, “Carbon-14 in methane sources and in atmospheric methane: the contribution from fossil carbon,” Science 245, 286–290 (1989). [CrossRef] [PubMed]
  8. M. R. Manning, D. C. Lowe, W. Melhuish, R. Spaarks, G. Wallace, C. A. M. Brenninkmeijer, R. C. McGill, “The use of radiocarbon measurements in atmospheric studies,” Radio-carbon 32, 37–58 (1990).
  9. P. D. Quay, S. L. King, J. Stutsman, D. O. Wilbur, L. P. Steele, I. Fung, R. H. Gammon, T. A. Brown, G. W. Farwell, P. M. Grootes, F. H. Schmidt, “Carbon isotopic composition of atmospheric CH4: fossil and biomass burning source strengths,” Global Biogeochem. Cycles 5, 25–47 (1991). [CrossRef]
  10. S. C. Tyler, “The global methane budget,” in Microbial Production and Consumption of Greenhouse Gases: Methane, Nitrogen Oxides, and Halomethanes, J. E. Rogers, W. B. Whitman, eds. (American Society for Microbiology, Washington, D.C., 1991), pp. 7–38.
  11. Usually the stable isotope ratios are expressed in the δ notationδ=(RsampleRstandard-1)1000(‰),where Rsample, Rstandard are the 13C/12C (or D/H, i.e., 2H/1H) ratios of the sample and a standard, respectively. Generally the PeeDee Belemnite (PDB) standard is used for 13C/12C ratios,12 whereas D/H ratios are referenced to the standard mean ocean water (SMOW) standard.13
  12. H. Craig, “Isotopic standards for carbon and oxygen and correction factors for mass-spectrometric analysis of carbon dioxide,” Geochim. Cosmochim. Acta 12, 133–149 (1957). [CrossRef]
  13. R. Hagemann, G. Nief, E. Roth, “Absolute isotopic scale for deuterium analysis of natural waters, absolute D/H ratio for SMOW,” Tellus 22, 712–715 (1970). [CrossRef]
  14. M. J. Whiticar, E. Faber, M. Schoell, “Biogenic methane formation in marine and freshwater environments: CO2 reduction vs. acetate fermentation—isotope evidence,” Geochim. Cosmochim. Acta 50, 693–709 (1986). [CrossRef]
  15. M. Wahlen, “The global methane cycle,” Ann. Rev. Earth Planet. Sci. 21, 407–426 (1993). [CrossRef]
  16. R. A. Burke, T. R. Barber, W. M. Sackett, “Seasonal variations of stable hydrogen and carbon isotope ratios of methane in subtropical freshwater sediments,” Global Biogeochem. Cycles 6, 125–138 (1992). [CrossRef]
  17. D. D. Coleman, J. B. Risatti, M. Schoell, “Fractionation of carbon and hydrogen isotopes by methane-oxidizing bacteria,” Geochim. Cosmochim. Acta 45, 1033–1037 (1981). [CrossRef]
  18. R. A. Burke, T. R. Barber, W. M. Sackett, “Methane flux and stable hydrogen and carbon isotope composition of sedimentary methane from the Florida Everglades,” Global Biogeochem. Cycles 2, 329–340 (1988). [CrossRef]
  19. M. J. Whiticar, “A geochemical perspective of natural gas and atmospheric methane,” Org. Geochem. 16, 531–547 (1990). [CrossRef]
  20. I. Levin, P. Bergamaschi, H. Dörr, D. Trapp, “Stable isotopic signature of methane from major sources in Germany,” Chemosphere 26, 161–177 (1993). [CrossRef]
  21. P. Bergamaschi, “Messungen der 13CH4/12CH4- und 12CH3D/12CH4-Verhältnisse an Proben atmosphärischer Methanquellen mittels Diodenlaserabsorptionsspektrospkopie,” Ph.D. dissertation (Universität Heidelberg, Heidelberg, Germany, 1993).
  22. W. D. Hermichen, H. Schütze, “Zur Bedeutung der molekularen Diffusion für die Stoff- und Isotopentrennung bei der Bildung und Zerstörung von Erdgaslagerstätten,” Isotopenpraxis 23, 285–289 (1987). [CrossRef]
  23. E. J. Mroz, “Deuteromethanes: potential fingerprints of the sources of atmospheric methane,” Chemosphere 26, 45–53 (1993). [CrossRef]
  24. R. Bösinger, “Isotopenmessungen an atmosphärischem und quellnahem Methan,” Ph.D. dissertation (Universität Heidelberg, Heidelberg, Germany, 1990).
  25. D. C. Lowe, C. A. M. Brenninkmeijer, “Determination of the isotopic composition of atmospheric methane and its application in the Antarctic,” J. Geophys. Res. 96, 15455–15467 (1991). [CrossRef]
  26. I. Dumke, E. Faber, J. Poggenburg, “Determination of stable carbon and hydrogen isotopes of light hydrocarbons,” Anal. Chem. 61, 2149–2154 (1989). [CrossRef]
  27. C. R. Webster, R. D. May, “In situ stratospheric measurements of CH4, 13CH4, N2O, and OC18O using the BLISS tunable diode laser spectrometer,” Geophys. Res. Lett. 19, 45–48 (1992). [CrossRef]
  28. W. W. Wong, “Comparison of infrared and mass-spectrometric measurements of carbon-13/carbon-12 ratios,” Int. J. Appl. Radiat. Isot. 36, 997–999 (1985). [CrossRef] [PubMed]
  29. J. F. Becker, T. B. Sauke, M. Loewenstein, “Stable isotope analysis using diode laser spectroscopy,” Appl. Opt. 31, 1921–1927 (1992). [CrossRef] [PubMed]
  30. M. Wahlen, T. Yoshinari, “Oxygen isotope ratios in N2O from different environments,” Nature (London) 313, 780–782 (1985). [CrossRef]
  31. P. S. Lee, R. F. Majkowski, “High resolution infrared diode laser spectroscopy for isotope analysis—measurement of isotopic carbon monoxide,” Appl. Phys. Lett. 48, 619–621 (1986). [CrossRef]
  32. S. M. Anderson, J. Morton, K. Mauersberger, “Laboratory measurements of ozone isotopomers by tunable diode laser absorption spectroscopy,” Chem. Phys. Lett. 156, 175–180 (1989). [CrossRef]
  33. M. Schupp, P. Bergamaschi, G. W. Harris, P. J. Crutzen, “Development of a tunable diode laser absorption spectrometer for measurements of the 13C/12C ratio in methane,” Chemosphere 26, 13–22 (1993). [CrossRef]
  34. M. Schupp, “Entwicklung und Demonstration einer laserspektroskopischen Methode zur Messung des Kohlenstoffisoto-penverhältnisses in Methan,” Ph.D. dissertation (Universität Mainz, Mainz, Germany, 1992).
  35. M. Schupp, P. Bergamaschi, G. W. Harris, “Measurements of the 13C/12C ratio in methane using a tunable diode laser absorption spectrometer,” in Monitoring of Gaseous Pollutants by Tunable Diode Lasers, R. Grisar, H. Böttner, M. Tacke, G. Restelli, eds. (Kiuwer, Dordrecht, The Netherlands, 1992), pp. 343–352.
  36. A. Fried, B. Henry, J. R. Drummond, “Tunable diode laser ratio measurements of atmospheric constituents by employing dual fitting analysis and jump scanning,” Appl. Opt. 32, 821–827 (1993). [CrossRef] [PubMed]
  37. C. R. Webster, R. T. Menzies, E. D. Hinkley, “Infrared laser absorption: theory and applications,” in Laser Remote Chemical Analysis, R. M. Measures, ed. (Wiley, New York, 1988), pp. 163–272.
  38. The subscript indicates the measurement method: mass spectrometry (MS) or TDLAS; the superscript indicates the scale to which the δ values are referred (PDB, SMOW, reference). The measured gas (sample, reference, calibration) is identified within the parentheses.
  39. L. S. Rothman, R. R. Gamache, R. H. Tipping, C. P. Rinsland, M. A. H. Smith, D. Chris Benner, V. Malathy Devi, J.-M. Flaud, C. Camy-Peyret, A. Perrin, A. Goldman, S. T. Massie, L. R. Brown, R. A. Toth, “The hitran molecular database: editions of 1991 and 1992,” J. Quant. Spectrosc. Radiat. Transfer 48, 469–507 (1992). [CrossRef]
  40. R. A. Toth, L. R. Brown, R. H. Hunt, L. S. Rothman, “Line parameters of methane from 2385 to 3200 cm−1,” Appl. Opt. 20, 932–935 (1981). [CrossRef] [PubMed]
  41. We define the mean deviation Δδ 13C (ΔδD) asΔδ={1n∑i=1n[δMS(i)-δTDLAS(i)]2}1/2.This provides a better measure of the comparison than the slopes and intercepts of the regression lines, which in all cases were insignificantly different from unity and zero.
  42. L. S. Rothman, R. R. Gamache, A. Goldman, L. R. Brown, R. A. Toth, H. M. Pickett, R. L. Poynter, J.-M. Flaud, C. Camy-Peyret, A. Barbe, N. Husson, C. P. Rinsland, M. A. H. Smith, “The hitran database: 1986 edition,” Appl. Opt. 26, 4058–4097 (1987). [CrossRef] [PubMed]

Cited By

Alert me when this paper is cited

OSA is able to provide readers links to articles that cite this paper by participating in CrossRef's Cited-By Linking service. CrossRef includes content from more than 3000 publishers and societies. In addition to listing OSA journal articles that cite this paper, citing articles from other participating publishers will also be listed.

« Previous Article  |  Next Article »

OSA is a member of CrossRef.

CrossCheck Deposited