Project EARTH-09-RK2: Freezing of sea ice: models of salt flux to the polar oceans Supervisors:

• Main Authors: Dr Richard Katz, Dr Helen Johnson
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Cole; D. M. and L. H. Shapiro; 1998; Sea ice
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.506.2191; http://www.earth.ox.ac.uk/__data/assets/pdf_file/0002/10010/RK2.pdf

The freezing of sea water in polar regions has important implications for ocean circulation and hence for global climate. Cold and salty brine rejected from the ice contributes to the formation of oceanic deepwater. The process by which drainage of brine from growing ice occurs has implications for the timing and intensity of deepwater formation. This project will use numerical simulations and laboratory experiments to better constrain brine drainage from sea ice. Because ocean water has a large salt content, it freezes in ways that are different from pure water. Instead of a sharp phase boundary between ice and water, sea ice is underlain by a “mushy layer ” where ice-crystals (which have little or no salt) and brine coexist. The brine in this layer is colder and saltier than the water below and hence tends to sink. To do so, it must flow through the pores of the mushy layer. The permeability of this layer controls the rate that brine can drain from it. Brine that is retained in the mush will remix with water from the ice as it melts in the Spring---hence it will not