Scientists say a huge crack in Antarctica's Larsen C ice shelf grew an additional 11 miles in just six days.
The British research group, Project MIDAS, explained in a blog post that the crack has breached the zone of soft "suture" ice located near the Cole Peninsula.
"There appears to be very little to prevent the iceberg from breaking away completely," Project MIDAS noted.
The shelf is now just eight miles from breaking all the way through the ice front and forming one of the largest icebergs ever recorded.
"When it calves, the Larsen C Ice Shelf will lose more than 10 percent of its area to leave the ice front at its most retreated position ever recorded," Project MIDAS, explained.
A calving event would also fundamentally change the landscape of the Antarctic Peninsula. Project MIDAS will continue monitoring the crack and assessing its impact on the ice shelf.
What's most important is what happens when the ice shelf is no longer in its place.
Ice shelves are permanent, floating sheets of ice that connect to a landmass so they don't directly contribute to sea level rise when an iceberg breaks off.
But when an ice shelf collapses, glaciers that fed into it are able to flow more quickly into the sea, according to the National Snow and Ice Data Center. Unlike ice shelves, glaciers are land-based, so they do contribute to sea level rise.