Global budget of atmospheric carbonyl sulfide: Temporal and spatial variations of the dominant sources and sinks

Abstract

[1] The spatial and temporal variability of the global fluxes of carbonyl sulfide (COS) is discussed together with possible implications for total column atmospheric COS loading. The input of COS into the atmosphere is calculated as the sum of all known direct sources of COS plus the conversion of carbon disulfide (CS 2 ) and dimethyl sulfide (DMS) to COS by atmospheric oxidation processes. Recent models are used to predict COS, CS 2 , and DMS release from the oceans and COS uptake by soils, plants, and oceans. This forward approach to constructing global integrated COS fluxes has a large associated range of uncertainty. The best guess global annual-integrated COS net flux estimate does not differ from zero within the range of estimated uncertainty, consistent with the observed absence of long-term trends in atmospheric COS loading. Interestingly, the hemispheric time-dependent monthly fluxes are very close in phase for the Northern and Southern Hemispheres. The monthly variation of the Northern Hemisphere flux seems to be driven primarily by high COS vegetation uptake in summer, while the monthly variation of the Southern Hemisphere flux appears to be driven mostly by high oceanic fluxes of COS, CS 2 , and DMS in summer.

Positive trends in Southern Hemisphere carbonyl sulfide

“…The primary source of OCS is the ocean, which is both a direct source (through OCS emission) and an indirect source (due to oxidation of carbon disulfide, CS 2 , and dimethyl sulfide) [Kettle et al, 2002]. Other natural sources of OCS include volcanic outgassing and direct fluxes from wetland regions [Kettle et al, 2002;Kuai et al, 2014].…”

“…Other natural sources of OCS include volcanic outgassing and direct fluxes from wetland regions [Kettle et al, 2002;Kuai et al, 2014]. The removal of OCS from the atmosphere is dominated by soil and vegetation uptake, with minor contributions from reactions with the hydroxyl radical [Kettle et al, 2002]. Small anthropogenic sources of OCS are coal combustion, biomass burning, and aluminum production [Watts, 2000].…”

Characteristics and anthropogenic sources of carbonyl sulfide in Beijing

“…e l s e v i e r . c o m / j o u r n a l -o f -e n v i r o n m e n t a l -s c i e n c e s atmospheric COS sinks (Chin and Davis, 1993;Watts, 2000;Kettle et al, 2002;Montzka et al, 2007), and can strongly reduce the COS mixing ratios at ground levels (Campbell et al, 2008).…”

“…Besides the known natural sources such as the oceans (Ferek and Andreae, 1984;Johnson and Harrison, 1986;Mihalopoulos et al, 1992), volcanoes (Khalil and Rasmussen, 1984;Chin and Davis, 1993), anaerobic soil (Adams et al, 1981;Castro and Galloway, 1991;Chin and Davis, 1993;Kanda et al, 1995), marshes Peterson, 1984, 1985) and precipitation (Mu et al, 2004;Mu and Xu, 2009), approximately 25% of current COS in the atmosphere has been attributed to multifarious human activities (Aydin et al, 2002), including biomass burning (Crutzen et al, 1985;Nguyen et al, 1994), coal-fired power plants (Khalil and Rasmussen, 1984), chemical processing (Khalil and Rasmussen, 1984), aluminum production (Harnisch et al, 1995), sulfur recovery (Khalil and Rasmussen, 1984), and motor vehicles (Fried et al, 1992;Pos and Berresheim, 1993). On the other hand, vegetation uptake of COS is responsible for 50%-70% of atmospheric COS sinks (Chin and Davis, 1993;Watts, 2000;Kettle et al, 2002;Montzka et al, 2007), and can strongly reduce the COS mixing ratios at ground levels (Campbell et al, 2008).…”

“…e l s e v i e r . c o m / j o u r n a l -o f -e n v i r o n m e n t a l -s c i e n c e s atmospheric COS sinks (Chin and Davis, 1993;Watts, 2000;Kettle et al, 2002;Montzka et al, 2007), and can strongly reduce the COS mixing ratios at ground levels (Campbell et al, 2008).However, the estimation of global anthropogenic COS sources' strength varies from 0.04 ± 0.02 (Chin and Davis, 1993) to 0.124 ± 0.06 Tg/year (Watts, 2000) due to the small number of investigations of source inventories. Recently, an indirect method has been used for estimation of regional anthropogenic COS emissions based on the linear correlation of COS with CO mixing ratios and the regional CO emission estimates (Blake et al, 2004;Guo et al, 2010).…”