EAPSI: Parameterizing the Two Phase Nature of Platelet Ice for use in Numerical Models that Simulate Sea Ice, Ice Shelves, and Icy Moons

Buffo Jacob, Atlanta GA

Investigators

Abstract

The evolution of sea ice, ice shelves, and icy moons is crucial to understanding how polar regions affect Earth?s climate and ocean dynamics, and unraveling the evolution and potential habitability of icy moons. One difficulty in modeling these entities is the complex interface between the floating ice and the underlying ocean. Platelet ice is characterized by shards of ice forming below ice shelves that float up to this interface creating a slurry of both solid and liquid phases, necessitating complex physics to accurately describe its evolution. The field of platelet ice research is young, and while it is beginning to be incorporated into models of sea ice, no models of ice shelves or icy moons include the phenomenon. Dr. Natalie Robinson, a researcher for the National Institute of Water and Atmospheric Research in Wellington, is at the forefront of platelet ice research. This collaborative project will utilize Dr. Robinson?s extensive knowledge of platelet ice formation and properties to incorporate the physics of accumulating platelet ice into an existing multiphase model used to simulate ice shelves and icy moons; producing the first model that includes these dynamics. This project will modify an existing finite difference model used to simulate the two-phase nature of floating ice by incorporating the physics of mushy layer theory. The additional parameterization of the platelet ice formation and characteristics will strengthen this models ability to accurately simulate the basal processes of a variety of terrestrial and extraterrestrial environments. The main additions will be the propensity for platelet accretion to occur and the porosity of an accumulated platelet layer based on local ocean parameters. Collaboration with Dr. Robinson will allow for empirical observations of platelet layer characteristics to be quickly incorporated into a numerical model of ice-ocean interfaces that is primed for incorporation into climate, ocean, and icy moon systems models. This award under the East Asia and Pacific Summer Institutes program supports summer research by a U.S. graduate student and is jointly funded by NSF and the Royal Society of New Zealand.