Laboratory results have demonstrated that bubble plumes are a very efficient air‐water gas transfer mechanism. Because breaking waves generate bubble plumes, it could be possible to correlate the air‐sea gas transport velocity kL with whitecap coverage. This correlation would then allow kL to be predicted from measurements of apparent microwave brightness temperature through the increase in sea surface microwave emissivity associated with breaking waves. In order to develop this remote‐sensing‐based method for predicting air‐sea gas fluxes, a whitecap simulation tank was used to measure evasive and invasive kL values for air‐seawater transfer of carbon dioxide, oxygen, helium, sulfur hexafluoride, and dimethyl sulfide at cleaned and surfactant‐influenced water surfaces. An empirical model has been developed that can predict kL from bubble plume coverage, diffusivity, and solubility. The observed dependence of kL on molecular diffusivity and aqueous‐phase solubility agrees with the predictions of modeling studies of bubble‐driven air‐water gas transfer. It has also been shown that soluble surfactants can decrease kL even in the presence of breaking waves.

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A comparison of the recovery sites of vertical drift‐envelopes and of ballasted drift‐bottles released simultaneously at common locations in Nantucket Sound off Cape Cod substantiates a preliminary conclusion, based on small tank experiments and simple calculations, that vertical envelopes move more rapidly through the water due to direct wind influence than do ballasted bottles. The bottles therefore provide a truer indication of surface currents than do the envelopes.