Experimental determination of the diffusion coefficient of dimethylsulfide in water
Article first published online: 20 SEP 2012
Copyright 1993 by the American Geophysical Union.
Journal of Geophysical Research: Oceans (1978–2012)
Volume 98, Issue C9, pages 16481–16486, 15 September 1993
How to Cite
1993), Experimental determination of the diffusion coefficient of dimethylsulfide in water, J. Geophys. Res., 98(C9), 16481–16486, doi:10.1029/93JC01858., , , and (
- Issue published online: 20 SEP 2012
- Article first published online: 20 SEP 2012
- Manuscript Accepted: 8 JUL 1993
- Manuscript Received: 14 JAN 1993
Estimates of the sea-to-air flux of dimethylsulfide (DMS) are based on sea surface concentration measurements and gas exchange calculations. Such calculations are dependent on the diffusivity of DMS (DDMS), which has never been experimentally determined. In this study the diffusivity of DMS in pure water was measured over a temperature range of 5°–30°C. The measurements were made using a dynamic diffusion cell in which the diffusing gas flows over one side of an agar gel membrane and the inert gas flows over the other side. The diffusion coefficient can be estimated from either time dependent or steady state analysis of the data, with an estimated uncertainty of less than 8% (1σ) in each measurement. A best fit to all the experimental results yields the equation DDMS (in cm2 sec−1) = 0.020 exp (−18.1/RT), where R = 8.314 × 10−3 kJ mole−1 K−1 and T is temperature in kelvin. The values of DDMS obtained in this study were 7–28% larger than estimates from the empirical formula of Hayduk and Laudie (1974) which has previously been used for DMS in gas exchange calculations. Applying these values to seawater results in an increase of less than 5% in the global oceanic flux of DMS.