Major daytime sink

The major daytime sink for most organic sulfur compounds in the atmosphere is reaction with OH radicals (b 91 and it has been shown that reaction with NO3 is an important nighttime sink for DMS (10.111. As shown... 

Measurements of DMS from remote oceanic air exhibit diurnal cycles, with a pronounced daytime minimum and nighttime maximum. These variations are generally consistent with the idea that photochemically generated OH is the major sink of DMS. Detailed comparison of the data with current models of air/sea exchange suggest that either OH levels are greater than predicted or, more likely, that the piston velocities have been overestimated in the past... 

Figure 14 shows simulated concentration time profiles for the Fe(III) ligands pyruvate and oxalate, which have mostly lower concentrations during the daytime, when the photochemistry as described here is active. Thus, it has to be emphasized that Fe(III) complex photolysis reactions can be a major sink for the carboxylate species besides radical reactions, and it is crucial not to neglect these reactions when the fate of carboxylic acids in the atmospheric aqueous phase is considered. 

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