Abstract

Sea ice is a multi-phase material, consisting of a mixture of solid ice crystals and liquid brine. The properties of this mixture vary significantly during initial ice growth, from the growth of suspensions of frazil ice crystals in supercooled leads and polynyas through to a reactive porous material during consolidated congelation growth. The resulting mixture is also inherently multi-scale, with the macroscopic scales of interest such as ice depth or mixed layer depth being many order of magnitude larger than the scale of an individual ice crystal. This talk will provide an introduction to key continuum models of the multi-phase and multi-scale thermodynamics of sea ice growth. I will introduce so-called “mushy layer theory” for characterising the evolution of reactive porous sea ice, and also review theories of crystal suspension dynamics derived from a master equation. Selected case studies will be used to illustrate the application of these theories to predict ice accumulation rates, structural properties of ice, and interaction with convective flow.