Chemical Methods: Chemiluminscence, Chemical Amplification, Electrochemistry, and Derivation

We report on the development, characterization, and field deployment of a fast-time-response sensor for measuring ozone (O 3 ) and nitrogen dioxide (NO 2 ) concentrations utilizing chemical ionization time-of-flight mass spectrometry (CI-ToFMS) with oxygen anion (O − 2 ) reagent ion chemistry. We demonstrate that the oxygen anion chemical ionization mass spectrometer (Ox-CIMS) is highly sensitive to both O 3 (180 counts s −1 pptv −1 ) and NO 2 (97 counts s −1 pptv −1 ), corresponding to detection limits (3σ , 1 s averages) of 13 and 9.9 pptv, respectively. In both cases, the detection threshold is limited by the magnitude and variability in the background determination. The short-term precision (1 s averages) is better than 0.3 % at 10 ppbv O 3 and 4 % at 10 pptv NO 2 . We demonstrate that the sensitivity of the O 3 measurement to fluctuations in ambient water vapor and carbon dioxide is negligible for typical conditions encountered in the troposphere. The application of the Ox-CIMS to the measurement of O 3 vertical fluxes over the coastal ocean, via eddy covariance (EC), was tested during the summer of 2018 at Scripps Pier, La Jolla, CA. The observed mean ozone deposition velocity (v d (O 3 )) was 0.013 cm s −1 with a campaign ensemble limit of detection (LOD) of 0.0027 cm s −1 at the 95 % confidence level, from each 27 min sampling period LOD. The campaign mean and 1 standard deviation range of O 3 mixing ratios was 41.2 ± 10.1 ppbv. Several fast ozone titration events from local NO emissions were sampled where unit conversion of O 3 to NO 2 was observed, highlighting instrument utility as a total odd-oxygen (O x = O 3 + NO 2 ) sensor. The demonstrated precision, sensitivity, and time resolution of this instrument highlight its potential for direct measurements of O 3 ocean-atmosphere and biosphere-atmosphere exchange from both stationary and mobile sampling platforms.

show abstract

“…This was assessed quantitatively by calculation of the Allan variance as shown in Fig. S6 (Werle et al, 1993).…”

Section: Short-and Long-term Precisionmentioning

confidence: 99%

Simultaneous detection of ozone and nitrogen dioxide by oxygen anion chemical ionization mass spectrometry: a fast-time-response sensor suitable for eddy covariance measurements

2020

View full text Add to dashboard Cite

show abstract

“…Guesten et al (1992) point out that the sensitivity of the discs depend on humidity and that sensitivity does not decrease linearly with time. Signal drift as caused by the consumption of the reactive compounds on the target disc can occur, which is one of the reasons why each disc has a limited lifetime and careful and frequent calibrations are required (Weinheimer, 2006). Knowledge about the relationship between sensitivity, temperature and humidity and its variability over time with increased accumulated ozone exposure is lacking and fundamental understanding about the reaction mechanism of chemiluminescence is also missing.…”

Section: Introductionmentioning

confidence: 99%

Sources of uncertainty in eddy covariance ozone flux measurements made by dry chemiluminescence fast response analysers

et al. 2010

View full text Add to dashboard Cite

Abstract. We present a systematic intercomparison study of eddy covariance ozone flux measurements made using two fast response dry chemiluminescence analysers. Ozone deposition was measured over a well characterised managed grassland near Edinburgh, Scotland, during August 2007. A data quality control procedure specific to these analysers is introduced. Absolute ozone fluxes were calculated based on the relative signals of the dry chemiluminescence analysers using three different methods and the results are compared for both analysers. It is shown that the error in the fitted analyser calibration parameters required for the flux calculations provides a substantial source of uncertainty in the fluxes. The choice of the calculation method itself can also constitute an uncertainty in the flux as the calculated fluxes by the three methods do not agree within error at all times. This finding highlights the need for a consistent and rigorous approach for comparable datasets, such as e.g. in flux networks. Ozone fluxes calculated by one of the methods were then used to compare the two analysers in more detail. This systematic analyser comparison reveals half-hourly flux values differing by up to a factor of two at times with the difference in mean hourly flux ranging from 0 to 23% with an error in the mean daily flux of ± 12%. The comparison of analysers shows that the agreement in fluxes is excellent for some days but that there is an underlying uncertainty as a result of variable analyser performance and/or non-linear sensitivity.

show abstract

“…60 Dry chemiluminescence sensors have the simplest operation and have seen the most regular use for EC studies (Güsten et al, 1992;Tuovinen et al, 2004). However, dry chemiluminescence sensor discs require conditioning with high ozone (up to 400 ppbv for several hours) before operation, are known to degrade over time, and have high variability in sensitivity between sensor discs (Weinheimer, 2007). These factors have led to limitations in long term stability and to https://doi.org/10.5194/amt-2019-445 Preprint.…”

Section: Introductionmentioning

confidence: 99%

Simultaneous Detection of Ozone and Nitrogen Dioxide by Oxygen Anion Chemical Ionization Mass Spectrometry: A Fast Time Response Sensor Suitable for Eddy Covariance Measurements

Novak¹,

Vermeuel²,

Bertram³

2019

Preprint

View full text Add to dashboard Cite

Abstract. We report on the development, characterization, and field deployment of a fast time response sensor for measuring ozone (O3) and nitrogen dioxide (NO2) concentrations utilizing chemical ionization time-of-flight mass spectrometry (CI-ToFMS) with oxygen anion (O2−) reagent ion chemistry. We demonstrate that the oxygen anion chemical ionization mass spectrometer (Ox-CIMS) is highly sensitive to both O3 (180 ions s−1 pptv−1 pptv−1) and NO2 (97 ions s−1 pptv−1), corresponding to detection limits (3σ, 1 s averages) of 13 and 9.9 pptv, respectively. In both cases, the detection threshold is limited by the magnitude and variability in the background determination. The short-term precision (1 s averages) is better than 0.3% at 10 ppbv O3 and 4% at 10 pptv NO2. We demonstrate that the sensitivity of the O3 measurement to fluctuations in ambient water vapor and carbon dioxide is negligible for typical conditions encountered in the troposphere. The application of the Ox-CIMS to the measurement of O3 vertical fluxes over the coastal ocean, via eddy covariance (EC), was tested during summer 2018 at Scripps Pier, La Jolla CA. The observed mean ozone deposition velocity (vd(O3)) was 0.011 cm s−1 pptv−1 with a campaign ensemble limit of detection (LOD) of 0.0042 cm s−1 pptv−1 at the 95% confidence level, from each 27-minute sampling period LOD. The campaign mean and one standard deviation range of O3 mixing ratios were 38.9 ± 12.3 ppbv. Several fast ozone titration events from local NO emissions were sampled where unit conversion of O3 to NO2 was observed, highlighting instrument utility as a total odd oxygen (Ox = O3 + NO2) sensor. The demonstrated precision, sensitivity, and time resolution of this instrument highlight its potential for direct measurements of O3 ocean–atmosphere and biosphere–atmosphere exchange from both stationary and mobile sampling platforms.

show abstract

Chemical Methods: Chemiluminscence, Chemical Amplification, Electrochemistry, and Derivation

Cited by 13 publications

References 124 publications

Simultaneous detection of ozone and nitrogen dioxide by oxygen anion chemical ionization mass spectrometry: a fast-time-response sensor suitable for eddy covariance measurements

Simultaneous detection of ozone and nitrogen dioxide by oxygen anion chemical ionization mass spectrometry: a fast-time-response sensor suitable for eddy covariance measurements

Sources of uncertainty in eddy covariance ozone flux measurements made by dry chemiluminescence fast response analysers

Simultaneous Detection of Ozone and Nitrogen Dioxide by Oxygen Anion Chemical Ionization Mass Spectrometry: A Fast Time Response Sensor Suitable for Eddy Covariance Measurements

Contact Info

Product

Resources

About