HR: 0800h
AN: C41C-0212    [Abstracts]
TI: Effects of Boundary Layer Shear on the Morphology of Sea-Ice
AU: * Neufeld, J A
EM: jerome.neufeld@yale.edu
AF: Yale University, Dept. Geology and Geophysics PO Box 208109, New Haven, CT 06511 United States
AU: Wettlaufer, J S
EM: john.wettlaufer@yale.edu
AF: Yale University, Depts. of Physics and Geology and Geophysics PO Box 208109, New Haven, CT 06511 United States
AB: Shear flow in the sub ice boundary layer has been shown theoretically to induce a Bernoulli pressure variation which drives a morphological instability of the ice/liquid interface. ˙We investigate this process through an analogue to sea-ice system; the controlled solidification of an ammonium chloride solution in a laboratory flume. ˙We observe the growth of ``sea-ice'' in the presence of a range of geophysically realistic flow speeds and find a threshold speed above which a spatiotemporal variation of the phase fraction of the layer appears. ˙Upon removal of the external flow, the material returns to a uniform state. ˙We describe the systematics of the instability and its importance to the formation of sea ice and associated salt fluxes.
DE: 4207 Arctic and Antarctic oceanography
SC: Cryosphere [C]
MN: 2004 AGU Fall Meeting