Detection of snow avalanche locations using infrasound array data

• Published in: The Journal of the Acoustical Society of America 2016-10, Vol.140 (4), p.2994-2995
• Main Authors: Arai, Nobuo, Imai, Toshiaki, Otsuki, Masaya, Saito, Yoshihiko, Murayama, Takahiko, Iwakuni, Makiko
• Format: Article
• Language: English
• ISSN: 0001-4966; 1520-8524
• DOI: 10.1121/1.4969275

Infrasound observation measures the energy radiated by a snow avalanche into the atmosphere and can be used to detect snow avalanches over large areas. Our research team has conducted infrasound observation in Tokamachi, Niigata Prefecture, Japan, during the last three winter seasons. First, between January and April 2013, we deployed an infrasound sensor in front of a selected slope, obtained visual observations using a web camera, and identified infrasound signals generated by snow avalanches. During the second season (2013-2014 winter), we deployed two infrasound sensors approximately 1 km apart and obtained the attenuation characteristics of infrasound signals. In the 2014-2015 winter season, we deployed three sensors spaced at 1-2 km in a triangular array and attempted automatic extraction of signals associated with snow avalanches from observed raw data using time-domain processing. For the extracted signals, the locations of snow avalanches were estimated with the cross-correlation method. Twelve events were detected and located. The estimated locations were in an area with many steep slopes. An infrasound array monitoring system with real-time processing is capable of providing significant information on snow avalanche activity.