Researchers have confirmed that Antarctic started losing ice sheets approximately 5,000 years earlier than previously believed, according to a new study.

Antarctic is now losing around 159 billion tonnes of ice each year.

Ice sheets play an important role in global sea level rise, and, when combined, the Antarctic losses detected are enough to increase global sea levels by around 0.45 millimeters annually.

For the study, researchers at University of Cologne, Oregon State University, the Alfred-Wegener-Institute, University of Hawaii at Manoa, University of Lapland, University of New South Wales, and University of Bonn analyzed two sediment cores from the Scotia Sea between Antarctica and South America.

The cores contained "iceberg-rafted debris," according to the study.

"One of the iceberg events in our data that is of particular interest took place 14,600 years ago and coincided with a huge ice-sheet melt, the famous Meltwater Pulse 1A, which according to previous studies led to a global sea level rise of about 4 meters within 100 years," said Michael Weber of the University of Cologne in Germany, lead author of the study, according to a news release.

Researchers discovered increased amounts of debris during eight different episodes starting around 20,000 years ago, and continuing until 9,000 years ago.

The study confirms that melting of the Antarctic Sheet was not believed to have started until 14,000 years ago.

"This is the first direct evidence that shows that instabilities of the Antarctic ice sheet caused rapid sea level rise during the last glacial termination," said co-author Peter Clark, professor at the Oregon State University.

It also provides the first evidence that the Antarctic sheet contributed to what is known as meltwater pulse 1A, which is a period of very rapid sea level rise that started around 14,500 years ago.

The study was published this week in the journal Nature and is funded by the National Science Foundation.

See Now: OnePlus 6: How Different Will It Be From OnePlus 5?