An enormous iceberg (R) breaks off in the Antarctic in 2008 (AFP/File, Torsten Blackwood)

WASHINGTON (AFP) – A massive crack is growing wider in the Antarctic ice sheet and could break apart in the coming months, forming an iceberg the size of Brazil, NASA scientists warned Thursday.

The crack in western Antarctica’s Pine Island Glacier stretches for at least 18 miles (30 kilometers) and runs 165 feet (50 meters) deep.

The rift is widening at a rate of 6.5 feet (two meters) per day, said NASA project scientist Michael Studinger.

When the ice breaks apart, it will produce an iceberg more than 340 square miles (880 square kilometers), said Studinger who is part of the US space agency’s IceBridge project.

But the process is not a result of global warming, he said.

“We expect that later this year or early next year year there will be a pretty large iceberg forming as part of a natural cycle,” he added.

“These are cyclical events that occur every few years. The last big carving event occurred in 2001, so in general people have been expecting something to happen like that very soon.

“For us it is very exciting to actually see this while it is happening.”

The rift was first glimpsed in late September by scientists monitoring changes in the ice shelf via airplane flyovers in order to fill in the gaps left between a pair of satellites, ICESAT (Ice, Cloud and land Elevation Satellite), which ended in 2009, and ICESAT 2, which launches in 2016.

“Our study plan is based on our desire to avoid an ‘Oh-my-God moment’ in 2016 when ICESAT 2 launches and starts collecting data,” Studinger said.