Journal of Atmospheric Chemistry

, Volume 6, Issue 1, pp 35–46

Chemistry of organic traces in air

VIII: Sources and distribution of bromo- and bromochloromethanes in marine air and surfacewater of the Atlantic Ocean
  • Th. Class
  • K. Ballschmiter
Influence of Marine and Terrestrial Biosphere on the Chemical Composition of the Atmosphere

DOI: 10.1007/BF00048330

Cite this article as:
Class, T. & Ballschmiter, K. J Atmos Chem (1988) 6: 35. doi:10.1007/BF00048330

Abstract

The occurrence of CH2Br2, CH2BrCl, CH2I2, CH2ClI, CHBr3, CHBr2Cl, CHBrCl2 and CH2Br-CH2Br in marine air and seawater from various sampling sites in the region of the Atlantic Ocean have been measured and evaluated. A correlation exists between high concentrations of these compounds in air and in water and the occurrence of algae at the coastlines of various islands (The Azores, Bermuda, Tenerife) and in a region of high bioactivity in the Atlantic Ocean near the West African coast.

‘Real-world’ air-water concentration ratios derived from measurements in the open ocean identify the water mass near the African coast with its high primary production as a source for the above compounds. This region has to be discussed also as a possible secondary source in which CHBr2Cl, CHBrCl2 and CH2ClI can be formed via halogen-exchange. Whether CHBrCl2 and CH2ClI under-go transformation to CHCl3 and CH2Cl2, respectively, is open to further investigations.

Direct photolysis and degradation by OH-radicals lead to a gradient in the marine troposphere with reduced concentrations for the organobromides above the tropospheric boundary layer.

Key words

Halomethanesatmosphereseawateralgaehigh resolution gas chromatography

Copyright information

© D. Reidel Publishing Company 1988

Authors and Affiliations

  • Th. Class
    • 1
  • K. Ballschmiter
    • 1
  1. 1.Department of Analytical ChemistryUniversity of UlmUlmF.R.Germany