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After 18 years at sea, one of the pieces of Antarctica’s largest iceberg is drifting toward its own doom.
The iceberg, named B-15, broke away from Ross Ice Shelf in March 2000. The massive ice body remained afloat around Antarctica for many years and later fractured into even smaller pieces. One of those pieces, a coffin-shaped berg, has now entered a region where Antarctic icebergs melt rapidly. The berg B-15T has made its way into warmer waters and could be nearing the end of its voyage.
“The coffin shape is an accident of time and space, given the approximately 18.5-year voyage of B-15T,” said NASA glaciologist Chris Shuman. “We can only guess at the forces that have acted on this remnant of B-15 along the long way around Antarctica.”
Icebergs usually drift out of coastal waters with the currents. Then, wind pushes them out to the open sea and breaks them off. Some of those pieces may persist for decades while others head towards north into the southern Atlantic Ocean and eventually disappear.
When an astronaut aboard the International Space Station captured the image of the berg on September 23, 2018, it had already escaped the Southern Ocean. Later, Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite spotted it in the South Atlantic, between South Georgia and the South Sandwich Islands. South Georgia is the graveyard where giant Antarctic icebergs go to die
“The spooky shape of B-15T was acquired long before it moved into this iceberg graveyard. For more than a decade, B-15 had numerous collisions – smashing back into the Ross Ice Shelf where it originated, hitting bedrock along the coast, and bumping into other tabular icebergs. Statement reads. “Such collisions can be strong enough to abruptly fracture the crystalline ice and produce linear edges.”
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