The cycle of atmospheric CO

Abstract

New measurements of the CO-mixing ratio in the two hemispheres with the dissolved CO in surface seawater together with previous results are used to set up a detailed budget of CO in the atmosphere. It is shown that CO is produced by technological and by natural sources. The source strengths of both kinds of sources are of the same magnitude. The total CO-production rate is estimated to be 10 × 10¹⁴ g per year. The corresponding residence time is 0.5 years. From the observed latitudinal CO-distribution between the hemispheres the production of CO by the oxidation of methane in the troposphere is judged to be a minor source. CO is removed by microbiological processes at the soil surfaces, by photochemical consumption in the stratosphere, and probably also by reaction with OH radicals in the troposphere.