This image of the Larsen C ice shelf in Antarctica shows a crack in February. Park of the shelf broke off this week to form an iceberg with twice the volume of Lake Erie. (British Antarctic Survey via AP)

A vast iceberg with twice the volume of Lake Erie has broken off from a key floating ice shelf in Antarctica, scientists said Wednesday.

The iceberg broke off from the Larsen C ice shelf, scientists at the Swansea University in Britain said. The iceberg is said to weigh about a trillion tons.

The process, known as calving, happened in the past few days, when a 2,240-square-mile section broke away.

“We have been anticipating this event for months and have been surprised how long it took for the rift to break through the final few kilometers of ice,” said Adrian Luckman of Swansea University. “We will continue to monitor both the impact of this calving event on the Larsen C ice shelf and the fate of this huge iceberg.”

Scientists said the latest iceberg break won’t affect sea levels in the short term.

NASA and European Space Agency satellites have been watching the shelf and producing dramatic pictures of the break that have heightened interest beyond the scientific community. The final break was first revealed in a thermal infrared image from NASA’s MODIS satellite instrument.

Scientists from the Britain-based Antarctic project MIDAS have been monitoring the rift in Larsen C for years. The project describes the iceberg as one of the largest ever recorded.

The researchers say that the iceberg is likely to break into fragments and that while some of the ice may stay nearby for decades, portions of it may drift into warmer waters. They say much more study needs to be done to determine the cause of the break.

“At this point it would be premature to say that this was caused by global warming,” said Anna Hogg of the Center for Polar Observation and Modeling at the University of Leeds.

— Associated Press