A Fourier transform infrared trace gas and isotope analyser for atmospheric applications

Abstract. Concern in recent decades about human impacts on Earth's climate has led to the need for improved and expanded measurement capabilities of greenhouse gases in the atmosphere. In this paper we describe in detail an in situ trace gas analyser based on Fourier Transform Infrared (FTIR) spectroscopy that is capable of simultaneous and continuous measurements of carbon dioxide (CO2), methane (CH4), carbon monoxide (CO), nitrous oxide (N2O) and 13C in CO2 in air with high precision. High accuracy is established by reference to measurements of standard reference gases. Stable water isotopes can also be measured in undried airstreams. The analyser is automated and allows unattended operation with minimal operator intervention. Precision and accuracy meet and exceed the compatibility targets set by the World Meteorological Organisation – Global Atmosphere Watch for baseline measurements in the unpolluted troposphere for all species except 13C in CO2. The analyser is mobile and well suited to fixed sites, tower measurements, mobile platforms and campaign-based measurements. The isotopic specificity of the optically-based technique and analysis allows its application in isotopic tracer experiments, for example in tracing variations of 13C in CO2 and 15N in N2O. We review a number of applications illustrating use of the analyser in clean air monitoring, micrometeorological flux and tower measurements, mobile measurements on a train, and soil flux chamber measurements.

[1]  D. Griffith.  FT‐IR Measurements of Atmospheric Trace Gases and their Fluxes , 2006 .

[2]  Mark C. Abrams,et al.  Why chose a fourier transform spectrometer , 2001 .

[3]  D. Griffith,et al.  Train‐borne measurements of tropical methane enhancements from ephemeral wetlands in Australia , 2010 .

[4]  A. Vermeulen,et al.  Greenhouse gas observations from Cabauw Tall Tower (1992–2010) , 2011 .

[5]  Mark C. Abrams,et al.  Fourier Transform Spectrometry , 2001 .

[6]  Third Edition,et al.  Quantities, Units and Symbols in Physical Chemistry , 2009 .

[7]  T. B. Coplen.  EXPLANATORY GLOSSARY OF TERMS USED IN EXPRESSION OF RELATIVE ISOTOPE RATIOS AND GAS RATIOS , 2008 .

[8]  Dominik Brunner,et al.  Continuous isotopic composition measurements of tropospheric CO 2 at Jungfraujoch (3580 m a.s.l.), Switzerland: real-time observation of regional pollution events , 2010 .

[9]  William H. Press,et al.  Numerical recipes , 1990 .

[10]  Steve Zegelin,et al.  Atmospheric tomography: a Bayesian inversion technique for determining the rate and location of fugitive emissions. , 2012, Environmental science & technology.

[11]  P. Fraser,et al.  THE UOW FTIR TRACE GAS ANALYSER: COMPARISON WITH LOFLO, AGAGE AND TANK MEASUREMENTS AT CAPE GRIM AND GASLAB , 2010 .

[12]  Pushpam Kumar.  Agriculture (Chapter8) in IPCC, 2007: Climate change 2007: Mitigation of Climate Change. Contribution of Working Group III to the Fourth assessment Report of the Intergovernmental Panel on Climate Change , 2007 .

[13]  P. Werle,et al.  The limits of signal averaging in atmospheric trace-gas monitoring by tunable diode-laser absorption spectroscopy (TDLAS) , 1993 .

[14]  D. Griffith,et al.  Air-land exchanges of CO2, CH4 and N2O measured by FTIR spectrometry and micrometeorological techniques , 2002 .

[15]  H. Meijer,et al.  A single gas chromatograph for accurate atmospheric mixing ratio measurements of CO2, CH4, N2O, SF6 and CO , 2009 .

[16]  R. Weiss,et al.  A history of chemically and radiatively important gases in air deduced from ALE/GAGE/AGAGE , 2000 .

[17]  Timothy J. Johnson,et al.  An infrared spectral database for detection of gases emitted by biomass burning , 2010 .

[18]  T. Johnson,et al.  Gas-Phase Databases for Quantitative Infrared Spectroscopy , 2004, Applied spectroscopy.

[19]  P. Griffiths.  Fourier Transform Infrared Spectrometry , 2007 .

[20]  D. Griffith,et al.  Measured deuterium in water vapour concentration does not improve the constraint on the partitioning of evapotranspiration in a tall forest canopy, as estimated using a soil vegetation atmosphere transfer model , 2011 .

[21]  Martin J. Wooster,et al.  Absolute accuracy and sensitivity analysis of OP-FTIR retrievals of CO 2 , CH 4 and CO over concentrations representative of "clean air" and "polluted plumes" , 2011 .

[22]  A. Ravishankara,et al.  Nitrous Oxide (N2O): The Dominant Ozone-Depleting Substance Emitted in the 21st Century , 2009, Science.

[23]  Robert J. Anderson,et al.  Errors in absorbance measurements in infrared Fourier transform spectrometry because of limited instrument resolution , 1975 .

[24]  Peter R. Griffiths,et al.  Fourier Transform Infrared Spectrometry, Second Edition , 2007 .

[25]  D. W. Allan,et al.  Statistics of atomic frequency standards , 1966 .

[26]  Eric R. Crosson,et al.  High-accuracy continuous airborne measurements of greenhouse gases (CO2 and CH4) using the cavity ring-down spectroscopy (CRDS) technique , 2010 .

[27]  F. Phillips,et al.  Impact of dicyandiamide application on nitrous oxide emissions from urine patches in northern Victoria, Australia , 2008 .

[28]  Gang Li,et al.  The HITRAN 2008 molecular spectroscopic database , 2005 .

[29]  E. Dlugokencky,et al.  The role of carbon dioxide in climate forcing from 1979 to 2004: introduction of the Annual Greenhouse Gas Index , 2006 .

[30]  R. Leuning,et al.  Carbon and water fluxes over a temperate Eucalyptus forest and a tropical wet/dry savanna in Australia: measurements and comparison with MODIS remote sensing estimates , 2005 .

[31]  M. Wahlen,et al.  Interannual extremes in the rate of rise of atmospheric carbon dioxide since 1980 , 1995, Nature.

[32]  D. Griffith.  Synthetic Calibration and Quantitative Analysis of Gas-Phase FT-IR Spectra , 1996 .

[33]  J. Monteith,et al.  Principles of Environmental Physics , 2014 .

[34]  D. Haaland.  Methods to Include Beer's Law Nonlinearities in Quantitative Spectral Analysis , 1987 .

[35]  Samuel Hammer,et al.  Assessment of a multi-species in situ FTIR for precise atmospheric greenhouse gas observations , 2012 .

[36]  M. Heimann,et al.  Measurements of greenhouse gases and related tracers at Bialystok tall tower station in Poland , 2009 .

[37]  Ian White,et al.  Emissions of methane and nitrous oxide from Australian sugarcane soils. , 2010 .

[38]  Ian M. Jamie,et al.  Fourier Transform Infrared Spectrometry in Atmospheric and Trace Gas Analysis , 2006 .

[39]  P. Krummel,et al.  Differences between trends in atmospheric CO2 and the reported trends in anthropogenic CO2 emissions , 2010 .

[40]  D. Griffith,et al.  Precision trace gas analysis by FT-IR spectroscopy. 2. The 13C/12C isotope ratio of CO2. , 2000, Analytical chemistry.

[41]  D. Griffith,et al.  Precision trace gas analysis by FT-IR spectroscopy. 1. Simultaneous analysis of CO2, CH4, N2O, and CO in air. , 2000, Analytical chemistry.

[42]  R. Neubert.  A single gas chromatograph for accurate atmospheric mixing ratio measurements of CO 2 , 2009 .

[43]  D. Griffith,et al.  The Australian methane budget: Interpreting surface and train‐borne measurements using a chemistry transport model , 2011 .