May 31, 2017

The Larsen C Iceberg Is on the Brink of Breaking Off

Brian Kahn
Climate Central
The current location of the rift on Larsen C, as of May 31 2017. Image: Project MIDAS
The current location of the rift on Larsen C, as of May 31 2017. Image: Project MIDAS

The saga of the Larsen C crack is about reach its stunning conclusion. Scientists have watched a rift grow along one of Antarctica’s ice shelves for years. Now it’s in the final days of cutting off a piece of ice that will be one of the largest icebergs ever recorded.


The crack has spread 17 kilometers (11 miles) over the past six days, marking the biggest leap since January. It’s also turned toward where the ice shelf ends and is within 13 kilometers (eight miles) of making a clean break. There’s not much standing in its way either.


The growth follows reports from early May that the crack across the ice shelf had sprouted a branch, further underscoring how unstable the ice is becoming. Ice shelves float over water and essentially act as doorstops that hold back the vast Antarctic ice sheet.

The breakup is sure to be a spectacle both awe-inducing and horrifying. The iceberg on the verge of splitting off is estimated to be the size of Delaware, covering an area of 1,930 square miles. That’s equal to 10 percent of the ice shelf’s total area.


The changes don’t just stop with the Larsen C crack or the Antarctic Peninsula in general. The vast majority of ice shelves are losing volume due to rising ocean and air temperatures. That’s helped prime parts of West Antarctica for what might be unstoppable melt that could raise sea levels at least 10 feet.

Researchers also recently found meltwater ponds are much more common than previously thought. They even discovered a roaring seasonal waterfall on the Nansen Ice Shelf.