Flow induced on a waterbody by a source*

We analytically study the flow induced on a saltwater surface by a freshwater point source, and on a freshwater surface by a saltwater point source. In the former case, the fluid directly below the source rises upward, and near the surface it moves away from the source. In the latter case, the fluid directly below the source moves downwards, and near the surface it moves towards the source. The analytical results are compared with the experimental results obtained using the particle image velocimetry (PIV) technique.