Anthropogenic CO Emissions: Implications for the Atmospheric CO-OH-CH4 Cycle.

Present anthropogenic emissions of CO are apparently large enough to perturb the natural CO-OH-CH(4) cycle, which plays a crucial role in the self-cleansing processes in the troposphere. A significant increase in global concentrations of CO, CH(4) CH(3)Cl, and other trace gases may result from a decrease in the OH concentration caused by continued CO emissions. Even if the CO emissions were maintained at the present rate, increases in CO and CH(4) by the year 2025 might be as large as 50 and 25 percent, respectively. The time constants associated with the perturbations of the CO-OH-CH(4) cycle are of the order of a few decades. Perturbation of this cycle may also indirectly affect stratospheric chemistry.