N2O isotopocule measurements using laser spectroscopy: analyzer characterization and intercomparison

Simple item page
dc.contributor.authorHarris, SJen_AU
dc.contributor.authorLiisberg, Jen_AU
dc.contributor.authorXia, LLen_AU
dc.contributor.authorWei, Jen_AU
dc.contributor.authorZeyer, Ken_AU
dc.contributor.authorYu, LFen_AU
dc.contributor.authorBarthel, Men_AU
dc.contributor.authorWolf, Ben_AU
dc.contributor.authorKelly, BFJen_AU
dc.contributor.authorCendón, DIen_AU
dc.contributor.authorBlunier, Ten_AU
dc.contributor.authorSix, Jen_AU
dc.contributor.authorMohn, Jen_AU
dc.date.accessioned2021-11-23T02:05:41Zen_AU
dc.date.available2021-11-23T02:05:41Zen_AU
dc.date.issued2020-05-28en_AU
dc.date.statistics2021-10-13en_AU
dc.description.abstractFor the past two decades, the measurement of nitrous oxide (N2O) isotopocules – isotopically substituted molecules 14N15N16O, 15N14N16O and 14N14N18O of the main isotopic species 14N14N16O – has been a promising technique for understanding N2O production and consumption pathways. The coupling of non-cryogenic and tuneable light sources with different detection schemes, such as direct absorption quantum cascade laser absorption spectroscopy (QCLAS), cavity ring-down spectroscopy (CRDS) and off-axis integrated cavity output spectroscopy (OA-ICOS), has enabled the production of commercially available and field-deployable N2O isotopic analyzers. In contrast to traditional isotope-ratio mass spectrometry (IRMS), these instruments are inherently selective for position-specific 15N substitution and provide real-time data, with minimal or no sample pretreatment, which is highly attractive for process studies. Here, we compared the performance of N2O isotope laser spectrometers with the three most common detection schemes: OA-ICOS (N2OIA-30e-EP, ABB – Los Gatos Research Inc.), CRDS (G5131-i, Picarro Inc.) and QCLAS (dual QCLAS and preconcentration, trace gas extractor (TREX)-mini QCLAS, Aerodyne Research Inc.). For each instrument, the precision, drift and repeatability of N2O mole fraction [N2O] and isotope data were tested. The analyzers were then characterized for their dependence on [N2O], gas matrix composition (O2, Ar) and spectral interferences caused by H2O, CO2, CH4 and CO to develop analyzer-specific correction functions. Subsequently, a simulated two-end-member mixing experiment was used to compare the accuracy and repeatability of corrected and calibrated isotope measurements that could be acquired using the different laser spectrometers. Our results show that N2O isotope laser spectrometer performance is governed by an interplay between instrumental precision, drift, matrix effects and spectral interferences. To retrieve compatible and accurate results, it is necessary to include appropriate reference materials following the identical treatment (IT) principle during every measurement. Remaining differences between sample and reference gas compositions have to be corrected by applying analyzer-specific correction algorithms. These matrix and trace gas correction equations vary considerably according to N2O mole fraction, complicating the procedure further. Thus, researchers should strive to minimize differences in composition between sample and reference gases. In closing, we provide a calibration workflow to guide researchers in the operation of N2O isotope laser spectrometers in order to acquire accurate N2O isotope analyses. We anticipate that this workflow will assist in applications where matrix and trace gas compositions vary considerably (e.g., laboratory incubations, N2O liberated from wastewater or groundwater), as well as extend to future analyzer models and instruments focusing on isotopic species of other molecules. © Author(s) 2020. This work is distributed under the Creative Commons Attribution 4.0 Licence.en_AU
dc.identifier.citationHarris, S. J., Liisberg, J., Xia, L., Wei, J., Zeyer, K., Yu, L., Barthel, M., Wolf, B., Kelly, B. F. J., Cendón, D. I., Blunier, T., Six, J., & Mohn, J. (2020). N2O isotopocule measurements using laser spectroscopy: analyzer characterization and intercomparison. Atmospheric Measurement Techniques, 13(5), 2797-2831. doi:10.5194/amt-13-2797-2020en_AU
dc.identifier.issn1867-8548en_AU
dc.identifier.issue5en_AU
dc.identifier.journaltitleAtmospheric Measurement Techniquesen_AU
dc.identifier.pagination2797-2831en_AU
dc.identifier.urihttps://doi.org/10.5194/amt-13-2797-2020en_AU
dc.identifier.urihttps://apo.ansto.gov.au/dspace/handle/10238/12292en_AU
dc.identifier.volume13en_AU
dc.language.isoenen_AU
dc.publisherEuropean Geosciences Unionen_AU
dc.subjectNitrous oxideen_AU
dc.subjectLaser spectroscopyen_AU
dc.subjectMoleculesen_AU
dc.subjectLight sourcesen_AU
dc.subjectAbsorptionen_AU
dc.subjectIsotope ratioen_AU
dc.subjectSamplingen_AU
dc.titleN2O isotopocule measurements using laser spectroscopy: analyzer characterization and intercomparisonen_AU
dc.typeJournal Articleen_AU
Files
Original bundle
Now showing 1 - 2 of 2
Thumbnail Image
Name:
amt-13-2797-2020.pdf
Size:
5.81 MB
Format:
Adobe Portable Document Format
Description:
Download
Thumbnail Image
Name:
amt-13-2797-2020-supplement.pdf
Size:
8.8 MB
Format:
Adobe Portable Document Format
Description:
Download
License bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
license.txt
Size:
1.63 KB
Format:
Item-specific license agreed upon to submission
Description:
Download
Collections
Journal Articles