N2O mole fraction and isotopic composition at Dübendorf, Switzerland, from 2014-2016

DOI

The isotopic composition of atmospheric nitrous oxide (N2O) was measured semicontinuously, at ~35 min frequency in intermittent periods of 1-6 days over one and a half years, using preconcentration coupled to a quantum cascade laser spectrometer at the suburban site of Dübendorf, Switzerland. The achieved measurement repeatability was 0.08 per mil, 0.11 per mil, and 0.10 per mil for d18O, site preference, and d15Nbulk respectively, which is better than or equal to standard flask sampling-based isotope ratio mass spectrometry performance. The observed mean diurnal cycle reflected the buildup of N2O from isotopically light sources on an isotopically heavy tropospheric background. The measurements were used to determine the source isotopic composition, which varied significantly compared to chemical and meteorological parameters monitored at the site. FLEXPART-COSMO transport modeling in combination with modified Emissions Database for Global Atmospheric Research inventory emissions was used to model N2O mole fractions at the site. Additionally, isotopic signatures were estimated for different source categories using literature data and used to simulate N2O isotopic composition over the measurement period. The model was able to capture variability in N2O mole fraction well, but simulations of isotopic composition showed little agreement with observations. In particular, measured source isotopic composition exhibited one magnitude larger variability than simulated, clearly indicating that the range of isotopic source signatures estimated from literature significantly underestimates true variability of source signatures. Source d18O signature was found to be the most sensitive tracer for urban/industry versus agricultural N2O. d15Nbulk and site preference may provide more insight into microbial and chemical emission processes than partitioning of anthropogenic source categories.

Supplement to: Harris, Eliza; Henne, Stephan; Hüglin, Christoph; Zellweger, Christoph; Tuzson, Béla; Ibraim, Erkan; Emmenegger, Lukas; Mohn, Joachim (2017): Tracking nitrous oxide emission processes at a suburban site with semicontinuous, in situ measurements of isotopic composition. Journal of Geophysical Research: Atmospheres, 122(3), 1850-1870

Identifier
DOI https://doi.org/10.1594/PANGAEA.864305
Related Identifier https://doi.org/10.1002/2016JD025906
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.864305
Provenance
Creator Harris, Eliza ORCID logo; Mohn, Joachim ORCID logo
Publisher PANGAEA
Contributor Swiss Federal Laboratories for Materials Science and Technology
Publication Year 2016
Rights Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported; https://creativecommons.org/licenses/by-nc-sa/3.0/
OpenAccess true
Representation
Resource Type Supplementary Dataset; Dataset
Format text/tab-separated-values
Size 22536 data points
Discipline Earth System Research
Spatial Coverage (8.612 LON, 47.403 LAT); Switzerland
Temporal Coverage Begin 2014-07-01T17:33:16Z
Temporal Coverage End 2016-02-22T06:42:05Z