Dynamics analysis for flux of carbon dioxide across seasurface

The CO₂ exchange between atmosphere and seawater has been discussed. The physical process of exchange at seasurface is related closely with the atmospheric forcing. The result of a dynamics analysis of the CO₂ flux actvas the seasurface, and a computed example over the shelf area of the East China See are reported. The analysis and calculation show that the CO₂ vertical flux at seawater is mainly dependent on the CO₂ concentration difference between seawater and atmosphere. Its exchange velocity is affected by the friction velocity, solubility and resistivity. The agreement between this exchange velocity and recent wind tunnel experimental results is good with wind speed over the range 4-10 m/s. This flux can increase very fast with the increase of wind speed, but very small with the increase of temperature. During the three cruise expeditions in October 1993, and April and October 1994, the CO₂ vertical flux at eeasurface was directed downward over the shelf area of the East China Sea. Because the CO₂ partial pressure difference between seawater and atmosphere was a negative value, the flux value was -45.5 μg/(m²·h) in average.