Viscosity of the ice surface layer

Abstract

The thermal contraction of ice single crystals between 0 and −50 °C has been measured by the use of silicon strain gauges frozen on the crystal basal surface. The experimental results cannot be explained without assuming the existence of a Newtonian viscous layer at the ice-strain-gauge interface; this layer has a thickness which changes in temperature as predicted by Fletcher, and a viscosity intermediate between that of ice and that of supercooled water. The activation energy of the viscosity, (0.36±0.04) eV, seems to indicate that it is controlled by a vacancy mechanism in which only the vacancy migration is effective.

Surface premelting of water ice

“…The outermost layer shows a remarkably large variation of ~0.35 eV depending on the molecular environment of the molecule that is removed, as shown in figure 5. The average vacancy formation energy in the outermost layer is very comparable to the activation energy for translation reported by Mizuno and Hanafusa using NMR 14 and viscosity measurements that show transport to be mediated by vacancies 102 . Ordinarily crystalline materials are expected to show a single value for the vacancy energy in bulk, which is the case for bulk ice.…”

Uptake of SO2 by Polycrystalline Water Ice

“…Nevertheless, we would not expect such a reservoir to saturate readily, especially because viscosity effects associated with the close proximity of the ice walls would tend to decrease the diffusivities of impurities in these reservoirs relative to those in bulk liquid water. The diffusivity in veins and grain boundaries is unknown, but it is likely to be intermediate between that in ice and that in supercooled water (29,52).…”

Premelting Dynamics

“…Additionally, it has often been speculated that, although premelted liquid behaves as a Newtonian fluid sufficiently close to T m (Mantovani et al 1980, Tsionsky et al 2002, its viscosity can be much larger than that of bulk supercooled water and at lower temperatures may become non-Newtonian (Tsionsky et al 2003). Yet experiments on water confined between interfaces of mica reveal a constant shear viscosity down to the scale of just a few molecules (Raviv & Klein 2002) despite the potential ordering effect of the underlying solid (see Zhu & Granick 2003 and references therein).…”