Simulation of the crystal growth of platelet sea ice with di

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TitleSimulation of the crystal growth of platelet sea ice with diffusive heat and mass transferAbstractAntarctic coastal sea ice often grows in water that has been supercooled by interaction with an ice shelf. In these situations, ice crystals can form at depth, rise and deposit under the sea-ice cover to form a porous layer that eventually consolidates near the base of the existing sea ice. The least consolidated portion is called the sub-ice platelet layer. Congelation growth eventually causes the subice platelet layer to become frozen into the sea-ice cover as incorporated platelet ice. In this study, we simulate these processes in three dimensions using Voronoi dynamics to govern crystal growth kinetics. Platelet deposition, in situ growth and incorporation into the sea-ice cover are integrated into the model. Heat and mass transfer are controlled by diffusion. We extract and compare spatial-temporal distributions of porosity, salinity, temperature and crystallographic c-axes with observations from McMurdo Sound, Antarctica. The model captures the crystallographic structure of incorporated platelet ice as well as the topology of the sub-ice platelet layer. The solid fraction, which has previously been poorly constrained, is simulated to be âˆ¼0.22, in good agreement with an earlier estimate of 0.25 Â± 0.06. This property of the sub-ice platelet layer is important for biological processes, and for the freeboard-thickness relationship around Antarctica.AcknowledgementsP.W. has been supported by a University of Otago publishing bursary. We acknowledge Craig Stevens, Michael Williams and Sarah Wakes for helpful suggestions. The numerical results were simulated on the University of Otago Vulcan cluster. We acknowledge Lars Smedsrud, an anonymous reviewer and the editors, whose suggestions and comments helped improve and clarify earlier versions of the manuscript.

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1st AuthorWongpan, P.AuthorWongpan, P.Langhorne, P.Dempsey, D.Hahn-Woernle, L.Sun, Z.Year2015JournalAnnals of GlaciologyVolume56Number69Pages127-136DOI10.3189/2015AoG69A777URLhttps://www.scopus.com/inward/recor.....11d7c15d01ed5662f98ed8e36Keywordscrystal structurecrystallographydiffusionglaciologyheat transferice crystalice shelfmass transfermodelingsea ice, AntarcticaEast AntarcticaMcMurdo Sound, rank3Author KeywordsAntarctic glaciologySea iceSea-ice growth and decaySea-ice modellingSea-ice/ice-shelf interactions

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TypeArticleCitationWongpan, P., Langhorne, P., Dempsey, D., Hahn-Woernle, L. and Sun, Z. (2015) Simulation of the crystal growth of platelet sea ice with diffusive heat and mass transfer. Annals of Glaciology, 56(69): 127-136 doi:10.3189/2015AoG69A777 IdentifierWongpan2015Relevancerank3