Atmospheric Lifetimes of Halogenated Hydrocarbons: Improved Estimations From an Analysis of Modeling Results. Issue 16 (17th August 2020) - Orkin, Vladimir L.
Abstract: Detailed results of computer modeling of halocarbon removal rates from the atmosphere are analyzed to find simple correlations useful for improving estimations of the atmospheric lifetimes of industrial chemicals based on the rate constants for their reactions with OH and O( 1 D) and their UV absorption spectra. This analysis is limited to relatively long‐lived chemicals that are well mixed in the troposphere. Key Points: A new semiempirical approach is developed for obtaining total atmospheric lifetimes of halocarbons from their photochemical properties The new approach yields partial lifetimes for methyl chloroform of 6.0 years for OH reaction and 48 years for stratospheric photolysis The methyl chloroform scaling approach is shown to yield total (rather than tropospheric) lifetime estimates for long‐lived halocarbons