Sulfur climate, global

Fig. 4-13 Calculated and observed annual wet deposition of sulfur in mgS/m per year. (Reprinted from "Atmospheric Environment," Volume 30, Feichter, J., Kjellstrom, E., Rodhe, H., Dentener, F., Lelieveld, and Roelofs, G.-J., Simulation of the tropospheric sulfur cycle in a global climate model, pp. 1693-1707, Copyright 1996, with permission from Elsevier Science.)...

Malin G (1996) The role of DMSP and DMS in the global sulfur cycle and climate regulation. In Kiene RP, Visscher P, Keller M, Kirst GO (eds) Biological and environmental chemistry of DMSP and related sulfonium compounds. Plenum, New York, pp 177-189 Malin G (1997) Sulphur, climate and the microbial maze. Nature 387 857-859 Malin G, Kirst GO (1997) Algal production of dimethyl sulfide and its atmospheric role. J Phycol 33 889-896... 

Equations (4.1) through (4.18) are supplemented in each cell of the spatial division of the ocean surface with initial conditions (Table 4.3). The boundary conditions for Equations (4.11) through (4.18) are zero. The calculation procedure to estimate sulfur concentration consists of two stages. First, at each time moment th for all cells Qiy, Equations (4.1)-(4.18) are solved by the quasi-linearization method, and all reservoirs of sulfur are estimated for ti+x = tf + At, where time step At is chosen from the convergence state of the calculation procedure. Then, at moment t(+1 using the climate unit of the global model these estimates are specified with account of the atmospheric transport and ocean currents over time At. 

The microbial biogenesis and catabolism of DMS, as well as other biogenic sulfur compounds, and the environmental factors affecting these processes deserve attention in order to understand the relationships between acid rain, climate and the global cycle of sulfur. 

Induction of chemokinetic ability also occurs in Alcaligenes strain M3A.60 Dimethyl sulfonio-propionate (DMSP) is an attractant for bacteria that have been induced to produce DMSP lyase. Such cells are attracted to DMSP at ecologically relevant concentrations, but uninduced cells do not respond to DMSP. Since DMSP lyase produces dimethylsulfide, which is important to global climate regulation, Zimmer-Faust et al.60 suggest that bacterial chemokinesis may play a critical role in global sulfur cycles and climate. 

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