bergy seltzer
The crackling, sizzling, popping sound made by a melting iceberg as ancient air bubbles trapped under enormous pressure during the glacier's formation are released into the water. The sound is audible from surprising distances and has been compared to soda fizzing or Rice Krispies in milk. It is the sound of air that was sealed into ice centuries or millennia ago finally escaping.
Etymology
A coinage from glaciology fieldwork — berg (iceberg) + seltzer (carbonated water). The iceberg fizzes.
Notes
One of those terms that shouldn't work but does — playful, precise, and describing something almost no one has heard.
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