World Library  

Add to Book Shelf
Flag as Inappropriate
Email this Book

Real-time Analysis of Δ13C- and Δd-ch4 in Ambient Air with Laser Spectroscopy: Method Development and First Intercomparison Results : Volume 8, Issue 8 (31/08/2015)

By Eyer, S.

Click here to view

Book Id: WPLBN0004000576
Format Type: PDF Article :
File Size: Pages 46
Reproduction Date: 2015

Title: Real-time Analysis of Δ13C- and Δd-ch4 in Ambient Air with Laser Spectroscopy: Method Development and First Intercomparison Results : Volume 8, Issue 8 (31/08/2015)  
Author: Eyer, S.
Volume: Vol. 8, Issue 8
Language: English
Subject: Science, Atmospheric, Measurement
Collections: Periodicals: Journal and Magazine Collection, Copernicus GmbH
Publication Date:
Publisher: Copernicus Gmbh, Göttingen, Germany
Member Page: Copernicus Publications


APA MLA Chicago

Der Veen, C. V., Rothe, M., Emmenegger, L., Brennwald, M. S., Popa, M. E., Mohn, J.,...Tuzson, B. (2015). Real-time Analysis of Δ13C- and Δd-ch4 in Ambient Air with Laser Spectroscopy: Method Development and First Intercomparison Results : Volume 8, Issue 8 (31/08/2015). Retrieved from

Description: Empa, Laboratory for Air Pollution & Environmental Technology, Dübendorf, Switzerland. In situ and simultaneous measurement of the three most abundant isotopologues of methane using mid-infrared laser absorption spectroscopy is demonstrated. A field-deployable, autonomous platform is realized by coupling a compact quantum cascade laser absorption spectrometer (QCLAS) to a preconcentration unit, called TRace gas EXtractor (TREX). This unit enhances CH4 mole fractions by a factor of up to 500 above ambient levels and quantitatively separates interfering trace gases such as N2O and CO2. The analytical precision of the QCLAS isotope measurement on the preconcentrated (750 ppm, parts-per-million, μmole/mole) methane is 0.1 and 0.5 ‰ for δ13C- and δD-CH4 at 10 min averaging time.

Based on replicate measurements of compressed air during a two-week intercomparison campaign, the repeatability of the TREX-QCLAS was determined to be 0.19 and 1.9 ‰ for δ13C and δD-CH4, respectively. In this intercomparison campaign the new in situ technique is compared to isotope-ratio mass-spectrometry (IRMS) based on glass flask and bag sampling and real time CH4 isotope analysis by two commercially available laser spectrometers. Both laser-based analyzers were limited to methane mole fraction and δ13C-CH4 analysis, and only one of them, a cavity ring down spectrometer, was capable to deliver meaningful data for the isotopic composition. After correcting for scale offsets, the average difference between TREX–QCLAS data and bag/flask sampling–IRMS values are within the extended WMO compatibility goals of 0.2 and 5 ‰ for δ13C- and δD-CH4, respectively. Thus, the intercomparison also reveals the need for reference air samples with accurately determined isotopic composition of CH4 to further improve the interlaboratory compatibility.

Real-time analysis of δ13C- and δD-CH4 in ambient air with laser spectroscopy: method development and first intercomparison results

Beck, V., Chen, H., Gerbig, C., Bergamaschi, P., Bruhwiler, L., Houweling, S., Röckmann, T., Kolle, O., Steinbach, J., Koch, T., Sapart, C. J., Van Der Veen, C., Frankenberg, C., Andreae, M. O., Artaxo, P., Longo, K. M., and Wofsy, S. C.: Methane airborne measurements and comparison to global models during BARCA, J. Geophys. Res.-Atmos., 117, D15310, doi:10.1029/2011JD017345, 2012.; Bergamaschi, P., Schupp, M., and Harris, G. W.: 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 spectro, Appl. Optics, 33, 7704–7716, doi:10.1364/AO.33.007704, 1994.; Bergamaschi, P., Brenninkmeijer, C. A. M., Hahn, M., Röckmann, T., Scharffe, D. H., Crutzen, P. J., Elansky, N. F., Belikov, I. B., Trivett, N. B. A., and Worthy, D. E. J.: Isotope analysis based source identification for atmospheric CH4 and CO sampled across Russia using the Trans-Siberian railroad, J. Geophys. Res., 103, 8227, doi:10.1029/97JD03738, 1998a.; Bergamaschi, P., Lubina, C., Königstedt, R., Fischer, H., Veltkamp, A. C., and Zwaagstra, O.: Stable isotopic signatures (Δ 13C, δD) of methane from European landfill sites, J. Geophys. Res., 103, 8251–8265, doi:10.1029/98JD00105, 1998b.; Bock, M., Schmitt, J., Beck, J., Schneider, R., and Fischer, H.: Improving accuracy and precision of ice core δD(CH4) analyses using methane pre-pyrolysis and hydrogen post-pyrolysis trapping and subsequent chromatographic separation, Atmos. Meas. Tech., 7, 1999–2012, doi:10.5194/amt-7-1999-2014, 2014.; Brand, W. A.: PreCon: a fully automated interface for the pre-GC concentration of trace gases on air for isotopic analysis, Isot. Environ. Healt. S., 31, 277–284, doi:10.1080/10256019508036271, 1995.; Brand, W. A. and Coplen, T. B.: Stable isotope deltas: tiny, yet robust signatures in nature, Isot. Environ. Healt. S., 48, 393–409, doi:10.1080/10256016.2012.666977, 2012.; Brass, M. and Röckmann, T.: Continuous-flow isotope ratio mass spectrometry method for carbon and hydrogen isotope measurements on atmospheric methane, Atmos. Meas. Tech., 3, 1707–1721, doi:10.5194/amt-3-1707-2010, 2010.; Coplen, T. B.: Guidelines and recommended terms for expression of stable-isotope-ratio and gas-ratio measurement results., Rapid Commun. Mass Sp.., 25, 2538–2560, doi:10.1002/rcm.5129, 2011.; Curl, R. F., Capasso, F., Gmachl, C., Kosterev, A. A., McManus, J. B., Lewicki, R., Pusharsky, M., Wysocki, G., and Tittel, F. K.: Quantum cascade lasers in chemical physics, Chem. Phys. Lett., 487, 1–18, doi:10.1016/j.cplett.2009.12.073, 2010.; Deans, D. R.: A new technique for heart cutting in gas chromatography [1], Chromatographia, 1, 18–22, doi:10.1007/BF02259005, 1968.; Dlugokencky, E. J., Myers, R. C., Lang, P. M., Masarie, K. A., Crotwell, A. M., Thoning, K. W., Hall, B. D., Elkins, J. W., and Steele, L. P.: Conversion of NOAA atmospheric dry air CH4 mole fractions to a gravimetrically prepared standard scale, J. Geophys. Res.-At


Click To View

Additional Books

  • An Integrated Flask Sample Collection Sy... (by )
  • Seasonal Distribution of Aerosol Propert... (by )
  • Dimensionality Reduction in Bayesian Est... (by )
  • The Performance of Aeolus in Heterogeneo... (by )
  • Non-parametric and Least Squares Langley... (by )
  • Quantitative Measurement of Pm10 by Mean... (by )
  • Quantitative Infrared Absorption Cross S... (by )
  • Towards a 3-d Tomographic Retrieval for ... (by )
  • Measurement of Hono, Hnco, and Other Ino... (by )
  • The Collection 6 Modis Aerosol Products ... (by )
  • Ionospheric Correction of Gps Radio Occu... (by )
  • Atmospheric Aerosol Characterization wit... (by )
Scroll Left
Scroll Right


Copyright © World Library Foundation. All rights reserved. eBooks from World eBook Library are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.