Monitoring global ice loss with hydroacoustics

BBC : Different types of icebergs make different sounds as they break away from glaciers, according to a study published in Geophysical Research Letters. Oskar Glowacki of the Polish Academy of Sciences and colleagues placed underwater microphones in the ocean and listened to the rumbles, groans, and snaps emitted as ice calved off the Hans Glacier in Svalbard. Combining the acoustic data with time-lapse photography, the researchers discovered three distinct underwater acoustic signatures from the glacier. The data allowed them to distinguish among the various stages of the calving process and determine when they were occurring. To date, glaciers have been monitored primarily with satellites, which can track only large pieces of ice. Hydroacoustics could allow researchers to track smaller ice blocks and better monitor global ice loss as Earth’s temperature rises.