Gigantic Iceberg Breaks Off from Antarctica

loose tooth iceberg
Images courtesy ESA Sentinel-1A)

A gigantic iceberg roughly half the size of Rhode Island has calved from an ice shelf in East Antarctica, scientists with the Australian Antarctic Division said this week. 

The calving event took place last week, with the iceberg eventually separating from the ice shelf on September 26th. 

Scientists have been watching the section nearly two decades, giving it the name “Loose Tooth” because of how it was precariously attached. 

The iceberg, officially named D-28, measures approximately 1,636 square kilometers in size, or about 50km x 30km. 

The so-called Loose Tooth broke off from Amery Ice Shelf, the third largest ice shelf in Antarctica, located between Australia’s Davis and Mawson research stations. The last major calving event there took place in 1963–64.

“We first noticed a rift at the front of the ice shelf in the early 2000s and predicted a large iceberg would break off between 2010–2015,” said Scripps’ Professor Helen Amanda Fricker.

“I am excited to see this calving event after all these years. We knew it would happen eventually, but just to keep us all on our toes, it is not exactly where we expected it to be,” Professor Fricker said.

Researchers have been studying the Amery Ice Shelf since the 1960s, deploying instruments on the ice to measure the impact of ocean melt and ice flow.

“We don’t think this event is linked to climate change, it’s part of the ice shelf’s normal cycle, where we see major calving events every 60–70 years,” Fricker said.

Australian Antarctic Program glaciologist, Dr Ben Galton-Fenzi, said they picked up last week’s calving through satellite imagery.

“The calving will not directly affect sea level, because the ice shelf was already floating, much like an ice cube in a glass of water,” Dr Galton-Fenzi said. “But what will be interesting to see is how the loss of this ice will influence the ocean melting under the remaining ice shelf and the speed at which the ice flows off the continent.”