Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Letter
  • Published:

H2SO4-HNO3-H2O ternary system in the stratosphere

Abstract

RECENTLY, Friend et al.1 reported a comprehensive laboratory study of a system of air containing trace quantities of H2O, SO2, NH3 and O3. By varying the proportions of these trace gases and the conditions of radiation of ultraviolet light and temperature, they obtained some detailed information for studying the mechanism of formation of stratospheric sulphate particles. They proposed a chemical model to interpret their laboratory observations and other observed features of stratospheric aerosol. The possible role of nitric acid, however, which is relatively abundant in the stratosphere2, was not included in their investigation of stratosphere aerosol formation. Also, the possible solid phase of 75% H2SO4 by weight in water at −50° C, as discussed by Toon and Pollack3, was not taken into consideration in their proposed chemical model to interpret the formation mechanism of ammonium sulphate or ammonium persulphate particles in the stratosphere. Toon and Pollack examined some of the physical properties of nitric acid, sulphuric acid and ammonium sulphate in stratospheric thermodynamic conditions3. Using physical equilibrium phase diagram analysis techniques4, they compared the equilibrium vapour pressure over nitric acid solutions with observed water and nitric acid partial pressures in the stratosphere, and concluded that nitric acid cannot be present as an aerosol in the lower stratosphere. For sulphuric acid, they predicted that sulphuric acid aerosol particles in the stratosphere are 75% H2SO4 by weight in water, in agreement with observations by Rosen5. From the freezing curve of H2SO4 solutions6, Toon and Pollack pointed out that H2SO4 (75% in weight)–H2O (25%) aerosol particles should exist in the lower stratosphere either as a solid or as a supercooled liquid. If most of the stratospheric sulphuric acid aerosol particles are in the solid phase, then the chemical models for the formation of ammonium sulphate using solution chemistry in sulphuric acid would not be applicable.

This is a preview of subscription content, access via your institution

Access options

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Similar content being viewed by others

References

  1. Friend, J. P., Leifer, R., and Trichon, M., J. atmos. Sci., 30, 465 (1973).

    Article  ADS  CAS  Google Scholar 

  2. Lazrus, A. L., Gandrud, B., and Cadle, R. D., J. appl. Meteorol., 11, 389 (1972).

    Article  ADS  CAS  Google Scholar 

  3. Toon, O. B., and Pollack, J. B., J. geophys. Res., 78, 7051 (1973).

    Article  ADS  CAS  Google Scholar 

  4. Lewis, J. S., Astrophys. J. Lett., 152, L79 (1968); Icarus, 10, 365 (1969).

    Article  ADS  Google Scholar 

  5. Rosen, J. M., J. appl. Meteorol., 10, 1044 (1971).

    Article  ADS  Google Scholar 

  6. Giauque, W. F., Hornung, E. W., Kunzler, J. E., and Rubin, T. R., J. Am. chem. Soc., 82, 62 (1960).

    Article  ADS  CAS  Google Scholar 

  7. International Critical Tables, 4, (McGrawHill, New York, 1928).

  8. Rubin, T. R., and Giauque, W. F., J. Am. chem. Soc., 74, 800 (1952).

    Article  CAS  Google Scholar 

  9. Kunzler, J. E., and Giauque, W. F., J. Am. chem. Soc., 74, 5271 (1952).

    Article  CAS  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

KIANG, C., HAMILL, P. H2SO4-HNO3-H2O ternary system in the stratosphere. Nature 250, 401–402 (1974). https://doi.org/10.1038/250401a0

Download citation

  • Received:

  • Revised:

  • Issue Date:

  • DOI: https://doi.org/10.1038/250401a0

This article is cited by

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing