Hostname: page-component-78c5997874-8bhkd Total loading time: 0 Render date: 2024-11-16T17:02:11.307Z Has data issue: false hasContentIssue false

Initial Results of an Intercomparison of AMS-Based Atmospheric 14CO2 Measurements

Published online by Cambridge University Press:  09 February 2016

John Miller*
Affiliation:
NOAA Earth System Research Laboratory, Boulder, Colorado, USA CIRES, University of Colorado, Boulder, Colorado, USA
Scott Lehman
Affiliation:
INSTAAR, University of Colorado, Boulder, Colorado, USA
Chad Wolak
Affiliation:
INSTAAR, University of Colorado, Boulder, Colorado, USA
Jocelyn Turnbull
Affiliation:
INSTAAR, University of Colorado, Boulder, Colorado, USA Present address: GNS Science, Lower Hurt, New Zealand
Gregory Dunn
Affiliation:
INSTAAR, University of Colorado, Boulder, Colorado, USA Present address: Harvard University, Cambridge, Massachusetts, USA
Heather Graven
Affiliation:
Scripps Institution of Oceanography, San Diego, California, USA
Ralph Keeling
Affiliation:
Scripps Institution of Oceanography, San Diego, California, USA
Harro A J Meijer
Affiliation:
Centre for Isotope Research, University of Groningen, Groningen, the Netherlands
Anita Th Aerts-Bijma
Affiliation:
Centre for Isotope Research, University of Groningen, Groningen, the Netherlands
Sanne W L Palstra
Affiliation:
Centre for Isotope Research, University of Groningen, Groningen, the Netherlands
Andrew M Smith
Affiliation:
Australian Nuclear Science and Technology Organisation, Lucas Heights, Australia
Colin Allison
Affiliation:
CSIRO, Marine and Atmospheric Research, Aspendale, Australia
John Southon
Affiliation:
University of California, Irvine, California, USA
Xiaomei Xu
Affiliation:
University of California, Irvine, California, USA
Takakiyo Nakazawa
Affiliation:
Tohoku University, Sendai, Japan
Shuji Aoki
Affiliation:
Tohoku University, Sendai, Japan
Toshio Nakamura
Affiliation:
Nagoya University, Nagoya, Japan
Thomas Guilderson
Affiliation:
Lawrence Livermore National Laboratory, Livermore, California, USA
Brian LaFranchi
Affiliation:
Lawrence Livermore National Laboratory, Livermore, California, USA
Hitoshi Mukai
Affiliation:
National Institute for Environmental Studies, Tsukuba, Japan
Yukio Terao
Affiliation:
National Institute for Environmental Studies, Tsukuba, Japan
Masao Uchida
Affiliation:
National Institute for Environmental Studies, Tsukuba, Japan
Miyuki Kondo
Affiliation:
National Institute for Environmental Studies, Tsukuba, Japan
*
Corresponding author. Email: [email protected].

Abstract

This article presents results from the first 3 rounds of an international intercomparison of measurements of Δ14CO2 in liter-scale samples of whole air by groups using accelerator mass spectrometry (AMS). The ultimate goal of the intercomparison is to allow the merging of Δ14CO2 data from different groups, with the confidence that differences in the data are geophysical gradients and not artifacts of calibration. Eight groups have participated in at least 1 round of the intercomparison, which has so far included 3 rounds of air distribution between 2007 and 2010. The comparison is intended to be ongoing, so that: a) the community obtains a regular assessment of differences between laboratories; and b) individual laboratories can begin to assess the long-term repeatability of their measurements of the same source air. Air used in the intercomparison was compressed into 2 high-pressure cylinders in 2005 and 2006 at Niwot Ridge, Colorado (USA), with one of the tanks “spiked” with fossil CO2, so that the 2 tanks span the range of Δ14CO2 typically encountered when measuring air from both remote background locations and polluted urban ones. Three groups show interlaboratory comparability within l% for ambient level Δ14CO2. For high CO2/low Δ14CO2 air, 4 laboratories showed comparability within 2%. This approaches the goals set out by the World Meteorological Organization (WMO) CO2 Measurements Experts Group in 2005. One important observation is that single-sample precisions typically reported by the AMS community cannot always explain the observed differences within and between laboratories. This emphasizes the need to use long-term repeatability as a metric for measurement precision, especially in the context of long-term atmospheric monitoring.

Type
Atmospheric Carbon Cycle
Copyright
Copyright © 2013 by the Arizona Board of Regents on behalf of the University of Arizona 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Allison, CE, Francey, RJ, White, JWC, Vaughn, BH, Wahlen, M, Bollenbacher, A, Nakazawa, T. 2003. What have we learnt about stable isotope measurements from the IAEA CLASSIC? In: Report of the 11th WMO/IAEA Meeting of Experts on Carbon Dioxide Concentration and Related Tracer Measurement Techniques. Tokyo, Japan, 25–28 September 2001. Geneva: WMO/GAW. p 1730.Google Scholar
Committee on Methods for Estimating Greenhouse Gas Emissions. 2010. Verifying Greenhouse Gas Emissions: Methods to Support International Climate Agreements. Washington, DC: The National Academies Press. 109 p.Google Scholar
Fink, D, Hotchkis, M, Hua, Q, Jacobsen, G, Smith, AM, Zoppi, U, Child, D, Mifsud, C, van der Gaast, H, Williams, A, Williams, M. 2004. The ANTARES AMS facility at ANSTO. Nuclear Instruments and Methods in Physics Research B 223–224:109–15.Google Scholar
Graven, HD, Guilderson, TP, Keeling, RF. 2007. Methods for high-precision 14C AMS measurement of atmospheric CO2 at LLNL. Radiocarbon 49(2):349–56.CrossRefGoogle Scholar
Graven, HD, Stephens, BB, Guilderson, TP, Campos, TL, Schimel, DS, Campbell, JE, Keeling, RF. 2009. Vertical profiles of biospheric and fossil fuel-derived CO2 and fossil fuel CO2 : CO ratios from airborne measurements of Δ14C, CO2 and CO above Colorado, USA. Tellus B 61(3):536–46.Google Scholar
Graven, HD, Guilderson, TP, Keeling, RF. 2012. Observations of radiocarbon in CO2 at seven global sampling sites in the Scripps flask network: analysis of spatial gradients and seasonal cycles. Journal of Geophysical Research 117:D02303, doi:10.1029/2011JD016535.Google Scholar
Graven, HD, Xu, X, Guilderson, TP, Keeling, RF, Trumbore, SE, Tyler, S. 2013. Comparison of independent Δ14CO2 records at Point Barrow, Alaska. Radiocarbon, these proceedings, doi:10.2458/azu_js_rc.55.16220.Google Scholar
Hua, Q, Zoppi, U, Williams, AA, Smith, AM. 2004. Small-mass AMS radiocarbon analysis at ANTARES. Nuclear Instruments and Methods in Physics Research B 223–224:284–92.Google Scholar
Joint Committee for Guides in Metrology (JCGM). 2008. International Vocabulary of Metrology – Basic and General Concepts and Associated Terms. 3rd edition. Metrology, JCfGi, editor. Geneva: Bureau International des Poids et Mesures.Google Scholar
Kobayashi, K, Niu, E, Itoh, S, Yamagata, H, Lomtatidze, Z, Jorjoliani, I, Nakamura, K, Fujine, H. 2007. The compact 14C AMS facility of Paleo Labo Co., Ltd., Japan. Nuclear Instruments and Methods in Physics Research B 259(1):31–5.Google Scholar
Krakauer, NY, Randerson, JT, Primeau, FW, Gruber, N, Menemenlis, D. 2006. Carbon isotope evidence for the latitudinal distribution and wind speed dependence of the air-sea gas transfer velocity. Tellus B 58(5):390417.Google Scholar
Lehman, SJ, Miller, JB, Wolak, C, Southon, J, Tans, PP, Montzka, SA, Sweeney, C, Andrews, A, LaFranchi, B, Guilderson, TP, Turnbull, JC. 2013. Allocation of terrestrial carbon sources using 14CO2: methods, measurement and modeling. Radiocarbon, these proceedings, doi:10.2458/azu_js_rc.55.16392.Google Scholar
Levin, I, Kromer, B, Schmidt, M, Sartorius, H. 2003. A novel approach for independent budgeting of fossil fuel CO2 over Europe by 14CO2 observations. Geophysical Research Letters 30:2194, doi:10.1029/2003GL018477.Google Scholar
Levin, I, Naegler, T, Kromer, B, Diehl, M, Francey, RJ, Gomez-Pelaez, AJ, Steele, LP, Wagenbach, D, Weller, R, Worthy, DE. 2010. Observations and modelling of the global distribution and long-term trend of atmospheric 14CO2 . Tellus B 62(1):2646.Google Scholar
Masarie, KA, Langenfelds, RL, Allison, CE, Conway, TJ, Dlugokencky, EJ, Francey, RJ, Novelli, PC, Steele, LP, Tans, PP, Vaughn, B, White, JWC. 2001. NOAA/CSIRO Flask Air Intercomparison Experiment: a strategy for directly assessing consistency among atmospheric measurements made by independent laboratories. Journal of Geophysical Research 106(D17):20,44564.Google Scholar
Meijer, HAJ, Pertuisot, MH, van der Plicht, J. 2006. High-accuracy 14C measurements for atmospheric CO2 samples by AMS. Radiocarbon 48(3):355–72.Google Scholar
Miller, JB, editor. 2007. 13th WMO/IAEA Meeting of Experts on Carbon Dioxide Concentration and Related Measurement Techniques. Geneva: World Meteorological Organization. 217 p.Google Scholar
Miller, JB, Lehman, SJ, Montzka, SA, Sweeney, C, Miller, BR, Karion, A, Wolak, C, Dlugokencky, EJ, Southon, J, Turnbull, JC, Tans, PP. 2012. Linking emissions of fossil fuel CO2 and other anthropogenic trace gases using atmospheric (CO2)-14C. Journal of Geophysical Research-Atmospheres 117: D08302, doi:10.1029/2011JD017048.Google Scholar
Mook, WG, van der Plicht, J. 1999. Reporting 14C activities and concentrations. Radiocarbon 41(3):227–39.Google Scholar
Naegler, T, Ciais, P, Rodgers, K, Levin, I. 2006. Excess radiocarbon constraints on air-sea gas exchange and the uptake of CO2 by the oceans. Geophysical Research Letters 33: L11802, doi:10.1029/2005GL025408.Google Scholar
Nakamura, T, Niu, E, Oda, H, Ikeda, A, Minami, M, Ohta, T, Oda, T. 2004. High precision 14C measurements with the HVEE Tandetron AMS system at Nagoya University. Nuclear Instruments and Methods in Physics Research B 223–224:124–9.Google Scholar
Nakazawa, T, Morimoto, S, Aoki, S, Tanaka, M. 1993. Time and space variations of the carbon isotopic ratio of tropospheric carbon-dioxide over Japan. Tellus B 45(3):258–74.Google Scholar
Stuiver, M. 1983. International agreements and the use of the new oxalic acid standard. Radiocarbon 25(2):793–5.Google Scholar
Stuiver, M, Polach, H. 1977. Discussion: reporting of 14C data. Radiocarbon 19(3):355–63.Google Scholar
Turnbull, JC, Miller, JB, Lehman, SJ, Tans, PP, Sparks, RJ, Southon, J. 2006. Comparison of 14CO2, CO, and SF6 as tracers for recently added fossil fuel CO2 in the atmosphere and implications for biological CO2 exchange. Geophysical Research Letters 33: L01817, doi:10.1029/2005GL024213.Google Scholar
Turnbull, JC, Lehman, SJ, Miller, JB, Sparks, RJ, Southon, JR, Tans, PP. 2007. A new high precision 14CO2 time series for North American continental air. Journal of Geophysical Research 112: D11310, doi:10.1029/2006JD008184.CrossRefGoogle Scholar
Xu, XM, Trumbore, SE, Zheng, SH, Southon, JR, McDuffee, KE, Luttgen, M, Liu, JC. 2007. Modifying a sealed tube zinc reduction method for preparation of AMS graphite targets: reducing background and attaining high precision. Nuclear Instruments and Methods in Physics Research B 259(1):320–9.Google Scholar
Zhou, LX, Kitzis, D, Tans, P. 2009. Report of the Fourth WMO RoundRobin Reference Gas Intercomparison, 2002–2007. In: Report of the 14th WMO/IAEA Meeting of Experts on Carbon Dioxide Concentration and Related Tracer Measurement Techniques. Geneva: WMO/GAW. p 40–3.Google Scholar