DMS sea-air transfer velocity: Direct measurements by eddy covariance and parameterization based on the NOAA/COARE gas transfer model

Estimates of the DMS sea-air transfer velocity (k(DMS)) derived from direct flux measurements are poorly modeled by parameterizations based solely on wind speed and Schmidt number. DMS and CO2 flux measurements show k(CO2) to be a stronger function of wind speed than k(DMS). The NOAA/COARE gas flux parameterization, incorporating the bubble-mediated gas transfer theory of Woolf ( 1997), appears to do a better job reproducing the observations for both gases, illustrating the importance of trace gas solubility in sea-air exchange. The development of gas transfer parameterizations based on physical principles is still in its infancy, but recent advances in direct flux measurement methods provide an opportunity to evaluate the success of various modeling approaches for this critical geophysical process.