Tidal influence on the sea-to-air transfer of CH4 in the coastal ocean

Doshik Hahm, Guebuem Kim, Yong-Woo Lee, Sungh-Yun Nam, Kyung-Ryul Kim, Kuh Kim
2006 Tellus: Series B, Chemical and Physical Meteorology  
A B S T R A C T We obtained real-time monitoring data of water temperature, salinity, wind, current, CH 4 and other oceanographic parameters in a coastal bay in the southern sea of Korea from July 8 to August 15, 2003, using an environmental monitoring buoy. In general, the transfer velocity of environmental gases across the air-sea interface is obtained exclusively from empirical relationships with wind speeds. However, our monitoring data demonstrate that the agitation of the aqueous boundary
more » ... layer is controlled significantly by tidal turbulence, similar to the control exercised by wind stress in the coastal ocean. The sea-to-air transfer of CH 4 is enhanced significantly during spring tide due to an increase in the gas transfer velocity and vertical CH 4 transport from bottom water to the surface layer. Thus, our unique timeseries results imply that the sea-to-air transfer of gases, such as CH 4 , DMS, DMHg, N 2 O, CO 2 and 222 Rn, from highly enriched coastal bottom waters, is controlled not only by episodic wind events but also by regular tidal turbulence in the coastal ocean.
doi:10.1111/j.1600-0889.2005.00170.x fatcat:xc6k55mp45edpb7ldp6b5cj3ge