At the ocean’s edge, slabs of ice break off of glaciers and tumble into the water as icebergs. But these iceberg births are poorly understood. Scientists don’t know how the ice will break or how much the glacier will lose.
It turns out scientists needed to listen more carefully. A study recently accepted to the journal Geophysical Letters finds that sound can tell scientists how ice will break away from a glacier.
Each iceberg birth, also called a calving event, is different. Ice can break off of the top of the glacier, splashing into the ocean. A whole sheet can slide down the glacier’s edge.
Sometimes the action is all below the surface. Ice can break off the glacier underwater, then burst to the surface and float away.
In August of 2013, scientists used underwater microphones to record calving events at the Hans Glacier in Norway. They synchronized their recordings with time lapse photos of the glacier.
Each type of calving event was preceded by different rumbles, groans, snaps and splashes, which you can hear in this video from the American Geophysical Union:
As glaciers lose ice into the ocean, they contribute to rising sea levels. Recordings like these help scientists understand how glaciers lose ice and predict how much ice will break into the ocean.