Laboratory experiments on CO2 gas exchange with wave breaking
Shuo Li, Alexander V. Babanin, Fangli Qiao, Dejun Dai, Shumin Jiang, Changlong Guan
Abstract
Abstract The CO 2 gas transfer velocity ( ) 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 and waves, laboratory experiments are conducted in a wind-wave flume. Three types of waves are forced in the flume: modulational wave trains generated by a wave maker, wind waves with 10-meter wind speed ranging from 4.5 m/s to 15.5 m/s, and (mechanically-generated) modulational wave trains coupled with superimposed wind force. The wave height and wave orbital velocity are found to be well correlated with while wind speed alone can not adequately describe . To reconcile the measurements, non-dimensional equations are established in which gas transfer velocity is expressed as a main function of wave parameters and an additional secondary factor to account for influence of the wind.