Introduction to an Open Community Infrasound Dataset from the Actively Erupting Sakurajima Volcano, Japan

Abstract

Online Material: Movie of time‐synced visual and infrasound data of two explosions at Sakurajima Volcano, Japan. Active volcanoes are significant sources of seismic and acoustic radiation. Extensive work has shown that infrasound is an effective tool to study and monitor active volcanoes. Infrasound is now a regular tool utilized by volcano observatories to aid in volcano monitoring and hazard mitigation. Infrasound‐based studies are able to provide important information on eruption dynamics and to develop quantitative models of volcanic eruptions. In addition, volcanoes provide excellent acoustic sources for atmospheric propagation studies and can be used to infer atmospheric dynamics and structure (see Johnson and Ripepe, 2011; Fee and Matoza, 2013 for recent reviews on volcano infrasound). The number of infrasound sensors and studies is also increasing rapidly, including those deployed as part of the USArray Transportable (seismic) Array. Lastly, seismic and acoustic records provide complementary information on both volcanic and nonvolcanic sources and elastic wave propagation in the Earth and atmosphere (Arrowsmith et al. , 2010). Although the number of volcano infrasound stations and research studies has increased substantially in recent years, many questions remain unresolved. For example, current work is focused on the spatial and temporal variability of the atmosphere and how it affects infrasound propagation at distances of a few to thousands of kilometers (Johnson et al. , 2012; Fee and Matoza, 2013; Lacanna et al. , 2014). Other studies are beginning to assess the effects of complex topography and volcanic crater morphology on infrasound signals recorded at both local and regional distances (e.g., Matoza, Garces, et al. , 2009; Kim and Lees, 2011; Lacanna and Ripepe, 2012). To date, most volcano infrasound studies assume linear sound propagation from the source, yet this assumption may not be valid for all volcanic explosions and has not been tested …