Structure of refrozen cracks in first-year sea ice

• Published in: Canadian Journal of Physics
• Main Authors: Petrich, C, Haskell, T G, Langhorne, P J
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 2003
• Subjects: General Physics and Astronomy; McMurdo Sound; Antarc*; Antarctica; Sea ice
• Online Access: http://dx.doi.org/10.1139/p03-032; http://www.nrcresearchpress.com/doi/pdf/10.1139/p03-032

The structure of natural refrozen cracks in landfast first-year sea ice in McMurdo Sound, Antarctica, is examined in Spring. The alignment of inclusions, crystal structure, and two-dimensional salinity profiles are discussed and compared to freezing experiments on slots cut in sea ice sheets. The investigated cracks and slots are of the order of 20–30 cm wide and grown in ice of about 1–2.2 m thickness. Convection in the water column during the phase transition is modelled with the Finite Volume Method. We find that inclusions seem to align with the freezing front, and suggest that the crystal structure and salinity profile are influenced by buoyancy-driven convection inside refreezing cracks. PACS Nos.: 46.50+a, 62.20Mk