Air-Sea Gas Transfer Velocity in a Shallow Estuary

作者：Mork Eva Thorborg^*; Sorensen Lise Lotte; Jensen Bjarne; Sejr Mikael K

来源：Boundary-Layer Meteorology, 2014, 151(1): 119-138.

DOI：10.1007/s10546-013-9869-z

• Air-sea CO2 exchange
• Cospectral peak method
• Eddy covariance
• Estuaries
• Transfer velocity

The air-sea transfer velocity of was investigated in a shallow estuary in March to July 2012, using eddy-covariance measurements of fluxes and measured air-sea partial-pressure differences. A data evaluation method that eliminates data by nine rejection criteria in order to heighten parametrization certainty is proposed. We tested the data evaluation method by comparing two datasets: one derived using quality criteria related solely to the eddy-covariance method, and the other derived using quality criteria based on both eddy-covariance and cospectral peak methods. The best parametrization of transfer velocity normalized to a Schmidt number of 600 was determined to be: where is the wind speed in m at 10 m; is based on fluxes calculated by the eddy-covariance method and including the cospectral peak method criteria. At low wind speeds, the transfer velocity in the shallow water estuary was lower than in other coastal waters, possibly a symptom of low tidal amplitude leading to low intensity water turbulence. High transfer velocities were recorded above wind speeds of 5 m , believed to be caused by early-breaking waves and the large fetch (6.5 km) of the estuary. These findings indicate that turbulence in both air and water influences the transfer velocity.

• 出版日期2014-4