Giant Iceberg the Size of Delaware Is About to Break off Antarctica—Here's What Will Happens When It Does

One of the biggest icebergs ever recorded is about to break away from Antarctica's Larsen C ice shelf. The mass of ice, about the size of Delaware, is poised to break off from the Antarctic Peninsula "any day now," scientists monitoring the ice shelf said last week.

But what will happen when it does break away? Researchers from the European Space Agency (ESA) have been analyzing the soon-to-be iceberg as part of the Cryosat mission—its Earth observatory program. Using data collected, they have been able to work out the iceberg's "vital statistics."

"Using information from CryoSat, we have mapped the elevation of the ice above the ocean and worked out that the eventual iceberg will be about 190 meters (620ft) thick and contain about 1,155 cubic kilometers (277 cubic miles) of ice," Noel Gourmelen, from the University of Edinburgh said in a statement.

"We have also estimated that the depth below sea level could be as much as 210 meters (690ft)."

CryoSat Iceberg
Animation showing what the iceberg will look like when it breaks away. University of Edinburgh–N. Gourmelen

Scientists noticed a crack on the Larsen C ice shelf had grown significantly two years ago. In January, the rift extended over 111 miles and last month researchers announced it had grown by another 11 miles, leaving it connected to the main shelf by a section only eight miles long. The rift continues to grow at an ever increasing rate and will soon break off in what is known as a "calving event."

"The iceberg remains attached to the ice shelf, but its outer end is moving at the highest speed ever recorded on this ice shelf," scientists from the Larsen C monitoring group Project Midas said. "We still can't tell when calving will occur—it could be hours, days or weeks."

While calving events are a part of a natural process that happen all the time, the Larsen C berg will need to be monitored because of its huge size. It may pose a risk to ships traveling along maritime routes, so the ESA plans to track its route and how it changes over the coming months and years.

Larsen C ice shelf
The Larsen C ice shelf. This image shows the 111-mile rift that grew over two years, before a Delaware-sized iceberg broke away. John Sonntag/NASA

Anna Hogg, from the University of Leeds, said: "As for this new Larsen C berg, we are not sure what will happen. It could, in fact, even calve in pieces or break up shortly after. Whole or in pieces, ocean currents could drag it north, even as far as the Falkland Islands. If so it could pose a hazard for ships in Drake Passage."

Jonathan Kingslake, a glaciologist from Columbia University's earth and environmental science, previously told Newsweek that ice shelves act as a bottle cork, holding back the ice on the land. "If an ice shelf were to disappear, ice on the land would start to flow faster."

This is what will likely happen to the Larsen C ice shelf—the Larsen B shelf disintegrated in 2002 after a similar calving event.

While a huge iceberg is a "visually stunning event," it will not lead to any huge changes to the planet: "We're not worried about this causing anything really catastrophic," Kingslake said.