Wells, Mathew Graeme2009-05-262011-01-042009-05-262011-01-04b20820185http://hdl.handle.net/1885/48013In this thesis I address several topics concerning the interaction of convection and density stratification in oceans and lakes. I present experimental and theoretical investigations of the interaction between a localized buoyancy source and a heat flux through a horizontal boundary, and of the interactions between salt fingers and intermittent turbulence or shear. ¶ An extensive series of laboratory experiments were used to quantify the stratification and circulation that result from the combined presence of a localized buoyancy source and a heat flux through a horizontal boundary. Previous studies found that convection in the form of a turbulent buoyant plume tends to produce a stable density stratification, whereas the distributed flux from a horizontal boundary tends to force vigorous overturning and to produce well-mixed layers. A new result of this thesis is that a steady density profile, consisting of a mixed layer and a stratified layer, can exist when the plume buoyancy flux is greater than the distributed flux. ...enThe Australian National UniversitySaltfingers, salt fingers, double diffusion, convection, turbulence, gravity currents200110.25911/5d7a2b4e7f265