Effects of variation in background mixing ratios of N2, O2, and Ar on the measurement of δ18O–H2O and δ2H–H2O values by cavity ring-down spectroscopy

Johnson, Jennifer E.; Rella, Chris W.

doi:https://doi.org/10.5194/amt-10-3073-2017

Articles | Volume 10, issue 8

https://doi.org/10.5194/amt-10-3073-2017

© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.

https://doi.org/10.5194/amt-10-3073-2017

© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.

Articles | Volume 10, issue 8

Research article

|

24 Aug 2017

Research article |

| 24 Aug 2017

Effects of variation in background mixing ratios of N₂, O₂, and Ar on the measurement of δ¹⁸O–H₂O and δ²H–H₂O values by cavity ring-down spectroscopy

Jennifer E. Johnson and Chris W. Rella

Data sets

Effects of variation in background mixing ratios of N2, O2, and Ar on the measurement of δ18O-H2O and δ2H-H2O values by cavity ring-down spectroscopy J. E. Johnson and C. W. Rella https://doi.org/10.17605/OSF.IO/C7NSG

Short summary

Cavity ring-down spectrometers (CRDS) can make accurate measurements of trace gases when the inert gas background is constant but are prone to errors when the background is variable. Here, we report that in one CRDS analyzer (L2120-i, Picarro), these errors result from broadening, narrowing, and shifting of the target absorption lines as well as neighboring lines. New spectral acquisition and analysis strategies are needed to make CRDS measurements robust to variable backgrounds.