The oxidation of S(IV) during riming by cloud droplets |
| |
| Authors: | J V Iribarne L A Barrie |
| |
| Institution: | (1) Department of Physics, University of Toronto, Toronto, Ontario, Canada;(2) Atmospheric Environment Service, 4905 Dufferin St., M3H 5T4 Downsview, Ontario, Canada |
| |
| Abstract: | Experiments have been performed to investigate whether the process of freezing during riming in clouds may induce oxidation of dissolved SO2 to SO
4
2–
. The experiments were conducted in a cold room at varying temperatures between –6 and –15 °C. Solutions containing dissolved SO2 and NH4OH in various proportions, in the range of concentrations between 3×10–5 and 10–3 M, were sprayed. Rime was collected on a rotating cylinder and analyzed. Absorption of oxygen from laboratory air was prevented, except in the spray, to avoid spurious oxidation. Blank experiments were made at +3 to +6 °C. The results indicate clearly that, as the dominant cation becomes NH
4
+
rather than H+, substantial oxidation of S(IV) occurs during riming. This is consistent with redox reactions taking place as a result of charge separation at the ice-water interface during freezing. |
| |
| Keywords: | Sulphur dioxide oxidation clouds riming freezing potential |
| 本文献已被 SpringerLink 等数据库收录！ |
|
