The rift in Antarctica’s Larsen C ice shelf grew by around 17 kilometers over just the last week, leaving only a 13 kilometer tether keeping the enormous soon-to-be-iceberg from being set loose, according to researchers with the UK’s Project Midas.
This means that the calving event for this Larsen C ice shelf iceberg is probably within the very near future. The iceberg in question will very likely be one of the largest ever recorded once released, according to the researchers.
The head of Project Midas, Professor Adrian Luckman of Swansea University College of Science, commented on the most recent observations: “In the largest jump since January, the rift in the Larsen C Ice Shelf has grown an additional 17 km (11 miles) between May 25 and May 31, 2017. This has moved the rift tip to within 13 km (8 miles) of breaking all the way through to the ice front, producing one of the largest ever recorded icebergs.
“The rift tip appears also to have turned significantly towards the ice front, indicating that the time of calving is probably very close. The rift has now fully breached the zone of soft ‘suture’ ice originating at the Cole Peninsula and there appears to be very little to prevent the iceberg from breaking away completely.”
As we’ve noted in our earlier coverage on the subject, while the iceberg calving event may not mean too much on its own, it is likely to destabilize the whole Larsen C ice shelf, possibly leading directly to its disintegration — as occurred with the Larsen B ice shelf when a similar large calving event occurred.
This matters because it serves as an example of the rapidly occurring changes now being observed in the Antarctic region in connection with anthropogenic climate change. The region around the Larsen C ice shelf, it should be realized, is now one of the most rapidly warming places on the earth.
Professor Luckman continued: “When it calves, the Larsen C Ice Shelf will lose more than 10% of its area to leave the ice front at its most retreated position ever recorded; this event will fundamentally change the landscape of the Antarctic Peninsula.
“We have previously shown that the new configuration will be less stable than it was prior to the rift, and that Larsen C may eventually follow the example of its neighbour Larsen B, which disintegrated in 2002 following a similar rift-induced calving event.”