Dataset for Snow Attenuation of Infrasound Signals and Wind Noise

Infrasound monitoring of nuclear explosions, snow avalanches, and earthquakes may be seasonally impacted by snow burial of infrasound stations. A number of factors may impact infrasound in snowpacks including: increased attenuation of the earthquake signals, reductions in wind noise, and changes in the sound speed through the snowpack. To assess these factors we installed a vertical array of sensors in the Sawtooth mountains of Idaho that was naturally buried by snow throughout the 2021-2022 winter. Using 38 earthquake signals that were detected by the array we calculate the frequency-dependent attenuation coefficient of infrasound by snowpacks and the speed of the sound wave. The attenuation coefficients were undetectable between 0-8 Hz, but then rose to 0.1 dB/cm at around 12 Hz, and above 12 Hz maintained a relatively constant 0.1 db/cm attenuation. The speed of sound in the snow was measured at 160 ± 51 m/s, significantly sub-sonic. Finally, there was a significant reduction in the amount of background noise measured for snow-buried compared to free-air sensors with 24 dB of reduction observed for high-wind speeds with only 20 cm of snow burial. This study provides a clearer understanding of how snow burial will bias the ability of infrasound sensors to assess the power and timing of infrasound signals used to monitor for natural and man-made hazards.