Detection of avalanche locations using infrasound array data

Abstract

Infrasound observations can be used to measure the energy radiated by an avalanche into the atmosphere and detect avalanches over large areas. Accompanying significant improvements in avalanche dynamics research, the use of infrasound for avalanche monitoring has increased over the last few decades. Our research team conducted infrasound observations in Tokamachi, Niigata Prefecture, Japan, over the past few winter seasons. In the 2014-2015 winter season, we deployed three sensors spaced by 1-2 km in a triangular array and attempted to automatically extract signals associated with avalanches from the observed raw data using time-domain processing. The locations of avalanches were estimated from the extracted signals using the cross-correlation method. Twelve events were detected and located. The estimated locations were in an area with multiple steep slopes. An infrasound array monitoring system with real-time processing would be capable of providing significant amounts of information concerning avalanche activity in snow-covered regions.