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Spectroscopic detection of stratospheric hydrogen cyanide
Science (New York, N.Y.)
|October 16, 1981
Summary
Stratospheric hydrogen cyanide (HCN) was detected using infrared spectra from aircraft. The average vertical column amount above 12 km was 7.1 x 10^14 molecules/cm², indicating a mixing ratio of 170 pptv.
Area of Science:
- Atmospheric Chemistry
- Spectroscopy
- Stratospheric Science
Background:
- Hydrogen cyanide (HCN) is a significant trace gas in the stratosphere.
- Understanding HCN distribution is crucial for atmospheric chemistry and ozone layer studies.
- Previous measurements of stratospheric HCN have been limited.
Purpose of the Study:
- To identify and quantify hydrogen cyanide (HCN) in the stratosphere.
- To determine the vertical column amounts and mixing ratios of stratospheric HCN.
- To contribute to a better understanding of HCN's role in atmospheric processes.
Main Methods:
- Infrared spectroscopy was employed to analyze stratospheric absorption.
- Data were collected from a high-altitude aircraft during eight research flights.
- Absorption lines characteristic of hydrogen cyanide were identified in the spectra.
Main Results:
- Absorption features of hydrogen cyanide were successfully identified in stratospheric spectra.
- The average vertical column amount of HCN above 12 km was determined to be 7.1 ± 0.8 x 10^14 molecules/cm².
- An average mixing ratio of 170 parts per trillion by volume (pptv) was calculated for stratospheric HCN.
Conclusions:
- This study successfully quantified stratospheric hydrogen cyanide using aircraft-based infrared spectroscopy.
- The derived HCN column amounts and mixing ratios provide valuable data for atmospheric models.
- The findings enhance our knowledge of trace gas composition in the upper troposphere and stratosphere.
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