Item: Temperature gradient metamorphism is not a classical coarsening process
Title: Temperature gradient metamorphism is not a classical coarsening process
Proceedings: International Snow Science Workshop, Davos 2009, Proceedings
Authors: Bernd Pinzer and Martin Schneebeli, WSL Institute for Snow and Avalanche Research SLF, Davos, Switzerland
Abstract: The current understanding of snow metamorphism distinguishes two classes: equi-temperature metamorphism and temperature gradient metamorphism. The former is an example of a coarsening process similar to Ostwald ripening, i.e. larger particles grow at the expense of smaller particles. Observations of temperature gradient metamorphism in the field and in the laboratory suggested a similar picture for this process. However, we showed that water vapor transfer in snow under a temperature gradient is so large that the entire ice skeleton is renewed within a few days. This means that a "particle" of ice which is usually used to classify snow in the field is completely dissolved after a few days. The concept of growing and shrinking particles does not hold under these circumstances. Instead, the structure must be considered a very dynamic population, where new ice mass "is born" and "dies" continuously.
Keywords: temperature gradient, metamorphism, grain growth, vapor flux
Digital Abstract Not Available