Are chlorine atoms significant tropospheric free radicals?

摘要

Free radicals drive chemical reactions in the atmosphere. The most important, and widely recognized, atmospheric free radical is the hydroxyl radical, ~·OH, which initiates the oxidation of many species and leads to their removal from the atmosphere (1). Therefore, ~·OH has been referred to as the "atmospheric detergent." Indeed, it is responsible for removal of hydrocarbons, many climate-forcing gases, sulfur dioxides, nitrogen oxides, and many other minor constituents. A byproduct of this "OH-initiated oxidation of hydrocarbons in the troposphere, the lower part of the atmosphere, is often ozone, a significant air pollutant.