Hostname: page-component-5c6d5d7d68-ckgrl Total loading time: 0 Render date: 2024-08-07T00:30:22.407Z Has data issue: false hasContentIssue false

A Simple Procedure for Evaluating Global Cosmogenic 14C Production in the Atmosphere Using Neutron Monitor Data

Published online by Cambridge University Press:  18 July 2016

D C Lowe*
Affiliation:
National Institute of Water and Atmospheric Research, P.O. Box 14–901, Wellington, New Zealand
W Allan
Affiliation:
National Institute of Water and Atmospheric Research, P.O. Box 14–901, Wellington, New Zealand
*
Corresponding author. Email: d.lowe@niwa.cri.nz.
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Radiocarbon (14C) produced by cosmogenic processes in the atmosphere reacts rapidly with atomic oxygen to form 14CO. The primary sink for this species is oxidation by the OH radical, the single most important oxidation mechanism for pollutants in the atmosphere. Hence, knowledge of the spatial and temporal distribution of 14CO allows important inferences to be made about atmospheric transport processes and the distribution of OH. Because the chemical lifetime of 14CO against OH attack is relatively short, 1–3 months, its distribution in the atmosphere should show modulations due to changes in 14C production caused by variations in the solar cycle. In this work we present a simple methodology to provide a time series of global 14C production to help interpret time series of atmospheric 14CO measurements covering the whole of solar cycle 23. We use data from neutron monitors, a readily available proxy for global 14C production, and show that an existing 6-year time series of 14CO data from Baring Head, New Zealand, tracks changes in global 14C production at the onset of solar cycle 23.

Type
Articles
Copyright
Copyright © 2002 by the Arizona Board of Regents on behalf of the University of Arizona 

References

Brauers, T, Hausmann, M, Bister, A, Kraus, A, Dorn, HP. 2001. OH radicals in the boundary layer of the Atlantic Ocean 1. Measurements by long-path laser absorption spectroscopy. Journal of Geophysical Research 106:7399–414.CrossRefGoogle Scholar
Brenninkmeijer, CAM, Manning, MR, Lowe, DC, Wallace, GW, Sparks, RJ, Volz-Thomas, A. 1992. Interhemispheric asymmetry in OH abundance inferred from measurements of atmospheric 14CO. Nature 356:50–2.Google Scholar
Broecker, WS. 1994. Stratospheric contribution to the global bomb radiocarbon inventory: Model versus observation. Global Biogeochemical Cycles 8:377–84.CrossRefGoogle Scholar
Broecker, WS, Sutherland, S, Smethie, W, Peng, TS, Ostlund, G. 1995. Oceanic radiocarbon: separation of the natural and bomb components. Global Biogeochemical Cycles 9:263–88.Google Scholar
Castagnoli, G, Lal, D. 1980. Solar modulation effects in terrestrial production of carbon-14. Radiocarbon 22(2):133–58.Google Scholar
Cleveland, RB, Cleveland, WS, McRae, JE, Terpenning, I. 1988. STL: a seasonal-trend decomposition procedure based on loess. Journal of Official Statistics (Statistics Sweden) 6:373.Google Scholar
Holton, JR, Haynes, PH, McIntyre, ME, Douglass, AR, Rood, RB, Pfister, L. 1995. Stratosphere-troposphere exchange. Reviews of Geophysics 33:403–39.Google Scholar
Jacob, DJ. 1999. Introduction to atmospheric chemistry. Princeton: Princeton University Press.Google Scholar
Jöckel, P, Brenninkmeijer, CAM, Lawrence, M. 2000. Atmospheric response time of cosmogenic 14CO to changes in solar activity. Journal of Geophysical Research 105:6737–44.CrossRefGoogle Scholar
Jöckel, P, Lawrence, MG, Brenninkmeijer, CAM. 1999. Simulations of cosmogenic 14CO using the three-dimensional model MATCH: effects of 14C production distribution and the solar cycle. Journal of Geophysical Research 104:11,733–43.CrossRefGoogle Scholar
Jokipii, JR. 1991. Variations of the cosmic-ray flux with time. In: Sonett, MS, Giampapa, MS, Matthews, MS, editors. The sun in time. Tucson: University of Arizona. p 205220.Google Scholar
Lingenfelter, RE. 1963. Production of carbon 14 by cosmic ray neutrons. Reviews of Geophysics 1: 3555.Google Scholar
Lowe, DC, Brenninkmeijer, CAM, Manning, MR, Sparks, RJ, Wallace, GW. 1988. Radiocarbon determination of atmospheric methane at Baring Head, New Zealand. Nature 372:522–5.Google Scholar
Lal, D. 1992. Expected secular variation in the global terrestrial production rate of radiocarbon. In: Bard, E, Broecker, WS, editors. The Last Deglaciation: absolute and radiocarbon chronologies. NATO ASI series, Volume 12. Berlin: Springer-Verlag. p 113–26.Google Scholar
MacKay, C, Pandow, M, Wolfgang, R. 1963. On the chemistry of natural radiocarbon. Journal of Geophysical Research 68:3929–31.CrossRefGoogle Scholar
Mak, JE, Brenninkmeijer, CAM, Tamaresis, J. 1994. Atmospheric 14CO observations and their use in estimating carbon monoxide removal rates. Journal of Geophysical Research 99:22,915–22.Google Scholar
Mak, JE, Southon, JR. 1998. Assessment of tropical OH seasonality using atmospheric 14CO measurements from Barbados. Geophysical Research Letters 25: 2801–4.Google Scholar
Manning, MR, Lowe, DC, Melhuish, WH, Sparks, RJ, Wallace, GW, Brenninkmeijer, CAM, McGill, RC. 1990. The use of radiocarbon measurements in atmospheric studies. Radiocarbon 32(1):3758.Google Scholar
Masarik, J, Beer, J. 1999. Simulation of particle fluxes and cosmogenic nuclide production in the Earth's atmosphere. Journal of Geophysical Research 104:12,099111.CrossRefGoogle Scholar
Masarik, J, Reedy, RC. 1995. Terrestrial cosmogenic-nuclide production systematics calculated from numerical simulations. Earth and Planetary Science Letters 136:381–95.Google Scholar
Moss, R, Manning, M, Lowe, D, Ferretti, D, Knobben, R. 1998. Changes in atmospheric carbon monoxide in the Pacific region. In Clarkson, TS, editor. Workshop on the science of atmospheric trace gases, 1998. NIWA Technical Report 15. Wellington, New Zealand. p 74–7.Google Scholar
O'Brien, K. 1979. Secular variations in the prediction of cosmogenic isotopes in the earth's atmosphere. Journal of Geophysical Research 84:423–31.Google Scholar
Prinn, RG, Weiss, RF, Miller, BR, Huang, J, Alyea, FN, Cunnold, DM, Fraser, PJ, Hartley, DE, Simmonds, PG. 1995. Atmospheric trends and lifetime of CH3CCl3 and global OH concentrations. Science 269:187–92.Google Scholar
Quay, P, Stutsman, J, Wilbur, D, Snover, A, Dlugokencky, E, Brown, T. 1999. The isotopic composition of atmospheric methane. Global Biogeochemical Cycles 13: 445–61.Google Scholar
Spivakovsky, CM, Logan, JA, Nontzka, SA, Balkanski, YJ, Foreman-Fowler, M, Jones, DBA, Horowitz, LW, Fusco, AC, Brenninkmeijer, CAM, Prather, MJ, Wofsy, SC, McElroy, MB. 2000. Three-dimensional climatological distribution of tropospheric OH: update and evaluation. Journal of Geophysical Research 105:8931–80.CrossRefGoogle Scholar
Thompson, AM. 1992. The oxidizing capacity of the earth's atmosphere: probable past and future changes. Science 256: 1157–65.Google Scholar
Vogt, S, Herzog, GF, Reedy, RC. 1990. Cosmogenic nuclides in extraterrestrial materials. Reviews of Geophysics 28:253–75.CrossRefGoogle Scholar
Wahlen, M, Tanaka, N, Henry, R, Deck, B, Zeglen, J, Vogel, JS, Southon, J, Shemesh, A, Fairbanks, A, Broecker, W. 1989. Carbon-14 in methane sources and in atmospheric methane: The contribution from fossil carbon. Science 245:286–90.CrossRefGoogle ScholarPubMed