Published In

Atmospheric Measurement Techniques

Document Type

Article

Publication Date

3-2-2018

Abstract

We report results from a worldwide interlaboratory comparison of samples among laboratories that measure (or measured) stable carbon and hydrogen isotope ratios of atmospheric CH413C-CH4 and δD-CH4). The offsets among the laboratories are larger than the measurement reproducibility of individual laboratories. To disentangle plausible measurement offsets, we evaluated and critically assessed a large number of intercomparison results, some of which have been documented previously in the literature. The results indicate significant offsets of δ13C-CH4 and δD- CH4 measurements among data sets reported from different laboratories; the differences among laboratories at modern atmospheric CH4 level spread over ranges of 0.5 ‰ for δ13C-CH4 and 13 ‰ for δD-CH4. The intercomparison results summarized in this study may be of help in future at tempts to harmonize δ13C-CH4 and δD-CH4 data sets from different laboratories in order to jointly incorporate them into modelling studies. However, establishing a merged data set, which includes δ13C-CH4 and δD-CH4 data from multiple laboratories with desirable compatibility, is still challenging due to differences among laboratories in instrument settings, correction methods, traceability to reference materials and long-term data management. Further efforts are needed to identify causes of the interlaboratory measurement offsets and to decrease those to move towards the best use of available δ13C-CH4 and δD-CH4 data sets.

Description

© Author(s) 2018. This work is distributed under the Creative Commons Attribution 4.0 License.

Published by Copernicus Publications on behalf of the European Geosciences Union.

DOI

10.5194/amt-11-1207-2018

Persistent Identifier

http://archives.pdx.edu/ds/psu/23937

Share

COinS