Metamorphism during temperature gradient with undersaturated advective airflow in a snow sample

Snow at or close to the surface commonly undergoes temperature gradient metamorphism under advective flow, which alters its microstructure and physical properties. Time-lapse X-ray microtomography is applied to investigate the structural dynamics of temperature gradient snow metamorphism exposed to...

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Bibliographic Details
Published in:The Cryosphere
Main Authors: P. P. Ebner, M. Schneebeli, A. Steinfeld
Format: Article in Journal/Newspaper
Language:English
Published: Copernicus Publications 2016
Subjects:
geo
Online Access:https://doi.org/10.5194/tc-10-791-2016
http://www.the-cryosphere.net/10/791/2016/tc-10-791-2016.pdf
https://doaj.org/article/c40d814de5ce4dc8a166f55283d7b347
Description
Summary:Snow at or close to the surface commonly undergoes temperature gradient metamorphism under advective flow, which alters its microstructure and physical properties. Time-lapse X-ray microtomography is applied to investigate the structural dynamics of temperature gradient snow metamorphism exposed to an advective airflow in controlled laboratory conditions. Cold saturated air at the inlet was blown into the snow samples and warmed up while flowing across the sample with a temperature gradient of around 50 K m−1. Changes of the porous ice structure were observed at mid-height of the snow sample. Sublimation occurred due to the slight undersaturation of the incoming air into the warmer ice matrix. Diffusion of water vapor opposite to the direction of the temperature gradient counteracted the mass transport of advection. Therefore, the total net ice change was negligible leading to a constant porosity profile. However, the strong recrystallization of water molecules in snow may impact its isotopic or chemical content.