New research shows the Jakobshavn Glacier in Greenland to be the world's fastest-flowing glacier, as it has only sped up significantly in the past two decades.

According to BBC News, the Jakobshavn Glacier is widely believed to have produced the iceberg that sank the Titanic. The Greenland Ice Sheet has experienced recording melting in recent years and the glacier is flowing four times faster than it did in the 1990s.

The study, published in the journal Cryosphere, found the glacier had reached an average rate of 17km a year in 2012. A record pace, that would equate to more than 46m per day.

"As the glacier moves we can track changes between images to produce maps of the ice flow velocity," study lead author Ian Joughin, of the University of Washington's Polar Science Center, told BBC News. "We are now seeing summer speeds more than four times what they were in the 1990s on a glacier which at that time was believed to be one of the fastest, if not the fastest, glacier in Greenland."

Even after taking into account faster flowing rates in the summer and slower ones in the winter, the average annual uptick in speed is three times greater than it was some 20 years ago.

"We know that from 2000 to 2010 this glacier alone increased sea level by about 4/100 of an inch (1 mm). With the additional speed it likely will contribute a bit more than this over the next decade," Joughin said in a news release, adding the increase in ice flow is heightening the sea level.

The researchers said in their study they believe Jakobshavn is in an unstable state and will only retreat farther inland as time goes on. From 2012 to 2013, its front retreated more than a kilometer greater inland than it had in previous years.

"The thing that's remarkable about the Jakobshavn Glacier is that even after all the mass that it has already lost, it is able to keep doing it, year after year," co-author Benjamin Smith, a glaciologist at the UW's Polar Science Center, said in the release. "A smaller glacier would settle down after losing that much mass. Jakobshavn's ability to drain ice from the ice sheet is really exceptional among all of the glaciers in Greenland."