Densification and grain coarsening of melting snow

• Main Authors: Shiqiao, Zhou, Nakawo, M, Hashimoto, S, Sakai, A, Narita, H, Ishikawa, N
• Format: Article in Journal/Newspaper
• Language: English
• Published: Polar Research Institute of China - PRIC 2003
• Subjects: Advances in Polar Science; Polar Science
• Online Access: http://library.arcticportal.org/2249/; http://library.arcticportal.org/2249/1/A200301001.pdf

A field work was conducted at Moshiri in Japan. The work included intensive snow pit work, taking snow grain photos, recording snow and air temperatures, as well as measuring snow water content. By treating the snow as a viscous fluid, it is found that the snow compactive viscosity decreases as the density increases, which is opposite to the relation for dry snow. Based on the measurements of snow grain size, it is shown that, similar to the water saturated snow, the frequency distributions of grain size at different times almost have the same shape. This reveals that the water unsaturated melting snow holds the same grain coarsening behavior as the water saturated snow does. It is also shown that the water unsaturated melting snow coarsens much more slowly than the water saturated snow. The C value, which is the viscosity when the snow density is zero, is related to the mean grain size and found the decrease with increasing grain size. The decreasing rate of C value increases with decreasing grain coarsening rate.