Item: Improved apparatus for measuring specific surface area of snow by the methane adsorption method
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Title: Improved apparatus for measuring specific surface area of snow by the methane adsorption method
Proceedings: International Snow Science Workshop Proceedings 2018, Innsbruck, Austria
Authors:
- Akihiro Hachikubo [ Kitami Institute of Technology, Kitami, Japan ]
- Satoru Yamaguchi [ National Research Institute for Earth Science and Disaster Resilience, Nagaoka, Japan ]
- Teruo Aoki [ Okayama University, Okayama, Japan ]
Date: 2018-10-07
Abstract: The specific surface area (SSA) of snow is an important parameter that expresses the complexity of the deposited snow. In addition, SSA is a better indicator than the grain size in terms of revealing the complexity of snow. Recently, the SSA of snow has been measured in fields using an infrared reflectance optical method (i.e., IceCube). However, optical methods require calibration because they are indirect methods for measuring SSA of snow. Based on the Brunauer-Emmett-Teller (BET) method, gas adsorption analysis has been employed to measure the SSA of snow by a French group. We improved the device for the BET method and downsized it for field use. The measurable range of our device is 3-350 m2 kg−1, which covers the range of natural snow from coarse melt forms to fine precipitation particles with rimes. The SSA measured using the BET method showed good correlation with the diameters of the spherical ice balls obtained from microphotographs. Although the system requires liquid nitrogen as a cryogen for snow samples and a commercial power supply to operate a vacuum pump, we sampled and stored the snow sample cells in a dry shipper (vapor shipper; samples can be stored at liquid nitrogen temperature) in the field and measured their SSA in our laboratory.
Object ID: ISSW2018_P07.13.pdf
Language of Article: English
Presenter(s):
Keywords: specific surface area, BET, methane
Page Number(s): 682-684
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