研究那些冰~ Hints: disintegrate iceberg current 1/5 air bubbles

These icefalls disintegrate into brash ice. But when a large chunk of a glacier or an ice sheet breaks away, it floats off as an iceberg. At first these bergs are slab-like. But winds and waves above water and currents below slowly carve them into the loveliest of the shapes. A large berg can survive for up to ten years before it ultimately breaks up and melts. Only 1/5 of an iceberg is above the surface, the rest is hidden beneath the water. Streams of minute air bubbles released from the melting berg carve grooves in its submerged flanks.

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