Double-diffusive convection in Lake Kivu.

摘要: Double-diffusive staircases with a total of 230-350 mixed layers and sharp interfaces were observed in nine microstructure temperature profiles measured during February 2004 Lake Kivu. The presence these at depths. 120 m indicates that diapycnal turbulent mixing is weak vertical diffusive transport dominated by double diffusion. Contrary to previously investigated natural or laboratory double-diffusive systems, the dissolved gases CO(2) CH(4) contribute significantly density stratification, thereby influencing formation structure staircases. ratio (i.e., stabilizing effect substances destabilizing temperature) ranges between 2.0 4.5 large sections deep waters, implying high susceptibility (average thickness 0.48 m) are shown be state active convection. average (0.18 surprisingly constant independent large-scale stratification. heat fluxes correlate well steps across interfaces. Kivu receives inflows from subaquatic springs several depths maintain stratification disturb In comparison earlier observations 1972, appear have been reduced, leading accumulation waters. Conversely, strengthening main chemocline an increased discharge could responsible for recent changes nutrient cycling methane production lake.