The mass budgets of carbonyl sulfide, dimethyl sulfide, carbon disulfide and hydrogen sulfide

This study investigates the distribution and magnitudes of the global sources and sinks of carbonyl sulfide (OCS), hydrogen sulfide (H2S), carbon disulfide (CS2), and dimethyl sulfide (DMS). For OCS, H2S and CS2, balanced mass budgets are proposed,An inventory of sources has been assembled for dimethyl sulfide (DMS). For OCS, total global sources and sinks are estimated as 1.31 +/- 0.25 and 1.66 +/- 0.79 Tg a(-1), respectively. Global sources and sinks of H2S are estimated as 7.72 +/- 1.25 and 8.50 +/- 2.80 Tg a(-1), respectively. Estimates of sources and sinks of CS2 are 0.66 +/- 0.19 and 1.01 +/- 0.45 Tg a(-1),respectively. For DMS only a sources estimate has been prepared, 24.45 +/- 5.30 Tg a(-1). The budgets for OCS and DMS seem relatively secure, whilst those for H2S and CS2 contain much greater uncertainty. For DMS, more information on emissions from plants is required. For the other three species, data on soils and vegetation emissions are sparse, although the most urgent priorities might be to establish the role of freshwater wetlands and soils in non-tropical areas. (C) 2000 Elsevier Science Ltd. All rights reserved.