INTERNAL WAVES, UPWELLING, CONVECTION: WHICH FACILITATES GREENHOUSE GAS EVASION?
Friday, 18 December 2015: 17:00
2008 (Moscone West)
The diffusive flux of greenhouse gases can be considered as a two-step process: dissolved gases must be brought to the air-water interface and they must subsequently be transported across it. Internal waves are ubiquitous features in aquatic ecosystems. Via internal wave induced upwelling, dissolved gases can directly reach surface waters and their breaking, combined with eddies from cooling, can deliver them to the interface. Whether turbulence is greater near the air-water interface during periods with convective cooling or surface heating with high frequency near-surface internal waves is an unsettled question. Using data from time series temperature and oxygen arrays and turbulence computed from temperature-gradient microstructure profilers, we provide examples of fluxes from these processes in a tropical reservoir, a floodplain lake, a temperate lake during fall cooling, and an arctic lake at ice off and subsequent stratification.