Acoustic signals provide alternative method of monitoring glacial runoff

Scientists monitor melting glaciers to gauge the meltwater contribution to ocean and freshwater resources globally, while also observing the risk of glacial flooding. However, glacio-hydrological monitoring is expensive, requiring a substantial effort by observers or sophisticated technology with large volumes of data.

Now, scientists from Japan’s Hokkaido University, led by Evgeny A. Podolskiy, have proposed a safe, affordable, and effective approach for monitoring glacial discharge using sounds generated at the proglacial run-off site. The method, published in Geophysical Research Letters, is reportedly approximately 100 times cheaper than the most novel methods, non-invasive, quick to deploy, and can become a tool for long-term glacier monitoring.

Previous research linked inaudible (infrasound) signals to glacial runoffs, noting a daily variation in the recordings and a peak during the summer. It was hypothesised that these signals might be generated by the radiation of air-pressure waves from the glacial runoff. Consequently, it was suggested that glacier discharge could be measured by analysing the audible sounds that are also emitted by melting glaciers.