Sub‐Ice Platelet Layer Physics: Insights From a Mushy‐Layer Sea Ice Model

The sub-ice platelet layer (SIPL) is a highly porous, isothermal, friable of ice crystals and saltwater, that can develop to several meters in thickness under consolidated sea near Antarctic shelves. While the SIPL has been comprehensively described, details its physics are rather poorly understood. In this contribution we describe halo-thermodynamic mechanisms driving development stability mushy-layer model simulations, forced by thermal atmospheric oceanic conditions McMurdo Sound, Ross Sea, Antarctica. novelty these simulations they predict realistic analogue for SIPL. Two aspects essential: (a) large initial brine fraction imposed on newly forming ice, (b) rejection via advective desalination. appears once conductive heat fluxes become insufficient remove latent required freeze porous new ice. Favorable formation include cold air, supercooled waters, snow thick enough provide sufficient insulation. Thermohaline properties resulting from liquid fractions stabilize SIPL, particular low diffusivity. Intense convection within isothermal generates SIPL-consolidated contrast without transporting heat. Using standard physical constants free parameters, successfully predicts thicknesses at six locations. most were performed with 50 layers, an emerged moderate accuracy three layers proving low-cost representation large-scale climate models.