Transfer of SO₂ and other reactive gases across the air—sea interface^*

^*Work supported by the U.S. Energy Research and Development Administration

Abstract

Using results obtained from experimental studies of the atmospheric transport of sensible heat, water vapour and momentum over the sea, deposition velocities of soluble and reactive trace gases are evaluated. The deposition velocities that result vary with the height of observation; they are nearly linearly dependent upon wind speed and are a function of the prevailing stability regime. In near-neutral stratification, it appears best to take the deposition velocity to be about 0.13 % of the wind speed when observations are made at 10 m height. When data are collected at 1 m height, this factor becomes about 0.2 %. Although the evaluations are intended to apply particularly to the case of SO₂ transfer, consideration of the molecular diffusivities of other gases that are similarly reactive (e.g., NH₃, HCl, NO₂ and SO₃) suggests that less than 10 % error will result from adopting the present results for SO₂ for these gases as well. When the liquid phase resistance is important, as is the case for CO₂ for example, then the deposition velocities are decreased to a limiting lower value specific for each gas. The present model considers only the simpler case in which the liquid phase resistance is negligible.

Notes

^* Work supported by the U.S. Energy Research and Development Administration