Measurements of CH3O2NO2 in the upper troposphere
Autor: | B. A. Nault, C. Garland, S. E. Pusede, P. J. Wooldridge, K. Ullmann, S. R. Hall, R. C. Cohen |
---|---|
Jazyk: | angličtina |
Rok vydání: | 2015 |
Předmět: | |
Zdroj: | Atmospheric Measurement Techniques, Vol 8, Iss 2, Pp 987-997 (2015) |
Druh dokumentu: | article |
ISSN: | 1867-1381 1867-8548 39809390 |
DOI: | 10.5194/amt-8-987-2015 |
Popis: | Methyl peroxy nitrate (CH3O2NO2) is a non-acyl peroxy nitrate that is important for photochemistry at low temperatures characteristic of the upper troposphere. We report the first measurements of CH3O2NO2, which we achieved through a new aircraft inlet configuration, combined with thermal-dissociation laser-induced fluorescence (TD-LIF) detection of NO2, and describe the accuracy, specificity, and interferences to CH3O2NO2 measurements. CH3O2NO2 is predicted to be a ubiquitous interference to upper-tropospheric NO2 measurements. We describe an experimental strategy for obtaining NO2 observations free of the CH3O2NO2 interference. Using these new methods, we made observations during two recent aircraft campaigns: the Deep Convective Clouds and Chemistry (DC-3) and the Studies of Emissions and Atmospheric Composition, Clouds, and Climate Coupling by Regional Surveys (SEAC4RS) experiments. The CH3O2NO2 measurements we report have a detection limit (S/N = 2) of 15 pptv at 1 min averaging on a background of 200 pptv NO2 and an accuracy of ±40%. Observations are used to constrain the interference of pernitric acid (HO2NO2) to the CH3O2NO2 measurements, as HO2NO2 partially decomposes (~11%) along with CH3O2NO2 in the heated CH3O2NO2 channel used to detect CH3O2NO2. |
Databáze: | Directory of Open Access Journals |
Externí odkaz: |