An atom of hydrogen and an atom of oxygen bonded together as a hydroxyl radical (OH) is important in our atmosphere. Nature reports:
The hydroxyl (OH) radical is the key oxidant in the global atmosphere as it controls the concentrations of toxic gases like carbon monoxide and climate relevant gases like methane. In some regions, oxidation by chlorine (Cl) radical is also important, and in the stratosphere both OH and Cl radicals impact ozone.
More recently, the Proceedings of the National Academy of Sciences reports as follows:
Recent studies suggest that reactions that do not usually occur in bulk solution can occur spontaneously in small water droplets, possibly due to the naturally formed electric field at the air–water interface. We explore the atmospheric significance of this process by demonstrating efficient spontaneous production of interfacial hydroxyl radicals (OH) from aqueous droplets under ambient conditions. This interfacial OH production does not involve precursors or catalysts, such as light or heat, and is likely the largest aqueous OH source in atmospheric droplets at nighttime. The ubiquity of aqueous aerosols and cloud droplets and their possibly strong OH-producing capability suggests that we have to rethink atmospheric multiphase oxidation chemistry.A less technical treatment aimed at interested laypersons like me (and I assume you) describes it as the atmosphere cleaning itself up, getting rid of pollution. I conclude climate alarmists need to dial back their hysteria. Hat tip to Stephen Green, posting at Instapundit, for the link.
