Splitting Icebergs

Satellite imaging captured the break-up of a massive iceberg near South Georgia Island (visible at image bottom) in the southern Atlantic Ocean.

A Canadian ice-tracking service spotted a fissure running south to north though the A53A iceberg on March 1, indicating it was unstable and likely to split. Just days afterward on March 4, Envisat's Medium Resolution Imaging Spectrometer (MERIS) sensor captured the break. Both bergs are estimated to measure around 30 km (19 miles) in length. As a reference, South Georgia Island is approximately 180 km (112 miles) long.

The break up of A53A, which calved off the Larsen Ice Shelf in late April 2005, occurred in relatively warm waters, making it highly likely that numerous smaller icebergs and ice islands will calve off the two icebergs.

Several different processes can cause an iceberg to form, or ‘calve’, including deterioration from high temperatures or the sun's radiation, action from winds and waves or a collision with another iceberg.

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Image Credit: ESA