Journal of Atmospheric Chemistry

, Volume 7, Issue 2, pp 153–176

Measuring correlations between atmospheric oxygen and carbon dioxide mole fractions: A preliminary study in urban air

  • Ralph F. Keeling

DOI: 10.1007/BF00048044

Cite this article as:
Keeling, R.F. J Atmos Chem (1988) 7: 153. doi:10.1007/BF00048044


On 25 and 26 October 1986 the air in Cambridge, Massachusetts was monitored for O2 and CO2 mole fraction. O2 concentrations were detected from changes in the relative refractivity of dried air between two lines of 198Hg at 2537.269 and 4359.562 Å using dual-wavelength interferometry. Changes in oxygen mole fraction were resolved with two-minute time resolution to a precision of ±2.0 ppm. Changes in O2 were shown to be strongly anticorrelated with changes in CO2 as expected for combustion processes. The demonstrated instrumental capabilities are appropriate for measuring changes in O2 mole fraction in background air which could be of importance to a broad range of biogeochemical studies.

Key words

Atmospheric oxygenatmospheric carbon dioxidecarbon cycleurban airinterferometry

Copyright information

© Kluwer Academic Publishers 1988

Authors and Affiliations

  • Ralph F. Keeling
    • 1
  1. 1.Harvard UniversityCambridgeU.S.A.