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Increased stratospheric hydrogen chloride in the el chichon cloud
Science (New York, N.Y.)
|October 12, 1984
Summary
El Chichón Volcano eruptions significantly increased stratospheric hydrogen chloride (HCl) by 40% in 1982. This study observed no similar rise in hydrogen fluoride (HF) levels following the volcanic event.
Area of Science:
- Atmospheric Chemistry
- Volcanology
- Spectroscopy
Background:
- El Chichón Volcano erupted in March-April 1982, injecting aerosols into the stratosphere.
- Volcanic eruptions can alter atmospheric composition, including halogen concentrations.
Purpose of the Study:
- To measure the total column amount of hydrogen chloride (HCl) and hydrogen fluoride (HF) before and after the El Chichón eruptions.
- To assess the impact of volcanic aerosols on stratospheric HCl and HF levels.
Main Methods:
- Spectroscopic observations were conducted in the 20-40 degrees N latitude range.
- Measurements were taken before and 3-6 months after the El Chichón eruptions.
- Data analysis accounted for a 5% annual global secular increase in HCl.
Main Results:
- A significant increase of approximately 40% in the total column amount of hydrogen chloride (HCl) was observed after the eruptions.
- This increase in HCl was noted in the region affected by volcanic aerosols.
- No comparable increase was detected in the column amounts of hydrogen fluoride (HF).
Conclusions:
- The El Chichón volcanic aerosol cloud significantly enhanced stratospheric hydrogen chloride (HCl) concentrations.
- Volcanic aerosols appear to play a role in the release or transport of HCl in the stratosphere.
- Hydrogen fluoride (HF) concentrations were not similarly affected by the volcanic event.
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