Antarctica continues to dominate the news, with the discovery of lost continents, scientists stabbing each other and that amazing perfectly-rectangular iceberg. Speaking of that berg, its popularity has inspired NASA to forget about the dead Martian rover for a while and try and figure exactly how it formed. It did, and the answer is …
Not so fast! We might as well join NASA and milk this frozen squareberg for all it’s worth. After the tabular iceberg was discovered in October 2018 by NASA scientist Jeremy Harbeck while riding in a plane when he was supposed to be studying changes in the thickness of the glaciers and ice sheets, speculation on its pointed to A-68, the massive iceberg that broke off from the Larsen C Ice Shelf in 2017. This sounded plausible since A-68 was travelling into slightly warmer waters and banging into the coast and other icebergs. Ice on the thinner edges could easily break off along a straight line.
A-68 breaking away (NASA)
However, when it comes to tracking the lineage of icebergs, the proof is in the pictures. NASA went far above Jeremy Harbeck’s Operation IceBridge plane to images from its Landsat 8 and the European Space Agency’s Sentinel-1 satellites taken over the past few years. Scanning the Larsen C ice shelf, they found that the squareberg actually broke of from it rather than A-68 just weeks after the monster berg’s violent exit, which probably left the edges of Larsen C in a weakened state.
A-68 breaking away from another angle (NASA)
The image of the birth of the squareberg (seen here) shows just how tiny the 4 km long iceberg is in relation to A-68, which is often compared to states or small countries. What surprised NASA researchers more than its shape was that it stayed relatively intact for a year as it floated very close to both the ice-bull-in-a-china-shop A-68, which is constantly colliding with the Bawden Ice Rise, an elevated ice shelf on Larsen C, and other smaller icebergs. While still rectangular, it’s down to 1500 meters by 900 meters and tending towards a trapezoid with just two parallel sides.
Still, it’s pretty impressive … as is NASA’s quick work in using its satellites to accurately pinpoint its place of origin. Now, if they could just use the same satellites to find keys and remote controls …
Paul Seaburn (CLICK HERE TO READ AND SEE MORE)
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