Results from an experimental laboratory study of large-scale coastal buoyant outflows are presented. Such a flow can be described as a buoyant outflow exiting an estuary or strait into a dense ambient fluid. The system is rotating such that Coriolis effects are important: thus, the buoyant outflow exits the estuary as a front in approximate thermal wind balance. The characteristics and evolution of the buoyant outflow are examined, and dynamical arguments are presented that describe the behavior of the outflow.; Buoyant outflows are examined in a number of configurations: the coastal bathymetry and bay exit geometry are varied in a simplified but realistic manner to assess the effect such variations have on the buoyant outflow. It is found that these boundary conditions have a major impact on the fate of the outflow. A buoyant outflow interacting with the bottom is found to be strongly controlled by the steepness of the coastal bathymetry, or bottom slope. This control manifests itself by determining the width of the buoyant outflow, which affects the downshelf velocity and mixing within the current. Currents isolated from the bottom by a layer of ambient oceanic fluid are found to evolve independent of the bottom slope. However, the geometry of the bay exit has a large affect upon the development of such outflows. The configuration of the bay exit may cause flow separation: such separation may be significant enough that a recirculation region may form. This recirculation region, or bulge, tends to consume a large percentage of the source volume flux, resulting in a flow characterized by a large recirculating eddy, and a relatively weak downshelf coastal current. Lack of recirculation, however, produces a strong coastal current with little offshore growth. Thus, the fate of the freshwater discharge is controlled very dramatically by the source exit conditions.; Finally, the impact of an ambient current on a surface-advected buoyant outflow is examined. Such along shelf ambient currents are common, although typically weak, in nature. However, it was found that even a weak ambient current may have a large impact on the development of a buoyant outflow, greatly altering the magnitude of the upshelf transport, downshelf transport, and storage, of the source fluid in the region.
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