Natural Convection, Solute Trapping, and Channel Formation during Solidification of Saltwater

We present new experimental results relating to the growth and evolution of sea ice. These show, in particular, that brine initially remains trapped in the interstices of the sea ice, only draining into the underlying ocean once the depth of the sea-ice layer exceeds a critical value. A general theory for convection within mushy layers is applied to develop a hypothesis for when brine drainage occurs, which is tested against the experimental results.