The 2 gas transfer velocity (2 ) at air-sea interface is usually
parameterized with the wind speed, but to a great extent is defined by
waves and wave breaking. To investigate the direct relationship between
2 and waves, laboratory experiments are conducted in a wind-wave flume.
Three kind of waves are forced in the flume: monochromatic waves
generated by a wavemaker, mechanically-generated monochromatic waves
with superimposed wind forcing, and pure wind waves with 10-meter wind
speed ranging from 4.5 m/s to 15.5 m/s. The wave parameters are found to
be well correlated with 2 while wind speed alone can not adequately
describe 2 . To reconcile the data sets, non-dimensional empirical
formulae are established in which 2 is expressed as a function of wave
parameters as the dominant term and an enhancement factor to account for
additional influence of the wind.