Greenland’s Ice Sheet Is Melting Four Times Faster Than Expected

After the release of a new study, scientists are now concerned that the ice in Greenland is melting at a rate that is four times faster than expected. The study also found that the ice melt is coming from the land-fast ice sheet and not from Greenland’s glaciers.

As National Geographic points out, “the largest sustained ice loss from early 2003 to mid-2013 came from Greenland’s southwest region, which is mostly devoid of large glaciers.”

Previously, studies had focused on Greenland’s southeast and northwest regions where large chunks of ice are deposited from the ice melt into the Atlantic Ocean. However, the latest research has been drawn to southwest Greenland.

“We knew we had one big problem with increasing rates of ice discharge by some large outlet glaciers,” said Michael Bevis, the study’s lead author.

“But now we recognize a second serious problem: Increasingly, large amounts of ice mass are going to leave as meltwater, as rivers that flow into the sea.

According to Nature, the new study that was published in on January 21, Greenland is now losing ice at the “fastest rate in 350 years.” This was revealed via the comprehensive study that looked at ice cores, satellite data, and climate models.

Bevis, who is a geoscientist at Ohio State University, points out that the ice melt in Greenland hit a “tipping point” around 2002-2003. And, by 2012, it the annual loss of ice to melting was considered “unprecedented.”

As previously reported by the Inquisitr, Greenland’s ice sheet melt was already a concern last year when research brought attention to the ice melt. The previous study was based on ice melt data relating to an incident in 2012 that saw a higher than usual ice sheet runoff. As a result of this, scientists set about discovering what the normal rate of ice melt for Greenland was. Drilling deep into the existing layers of Greenland’s ice sheets, they were able to gather more data about yearly ice melts. As a result of this study, it was concluded by one of the study’s authors that Greenland’s ice melt had gone into “overdrive.”

The new study now backs up the previous study that the ice melt in Greenland could lead to rising sea levels over time. As National Geographic points out, some parts of Greenland’s ice sheet is 10,000 feet thick and “contains enough ice to raise sea levels 23 feet (7 meters).” It has also been calculated that Greenland has lost around 9 billion tons of ice which have attributed to a 25-millimeter rise in sea levels.

As for what is causing this massive ice melt in Greenland? It is believed that global warming of just 1 degree Celcius (1.8 degrees Fahrenheit) is a major contributor. A negative phase of the North Atlantic Oscillation (NAO), as well as the El Niño–Southern Oscillation (ENSO) cycle and coral bleaching, is also to blame.

Jason Box, a glaciologist at the Geological Survey of Denmark and Greenland, also believes that Bevis’ study shows that the ice sheet in southwest Greenland is considered susceptible to El Niño-like atmospheric cycles which leads to a change in the level of ice melt there.

Richard Alley, a glaciologist at Penn State, insists that if people do not pay heed to this acceleration in Greenland’s ice melt by reducing the burning of fossil fuels, then a predicted ice melt of all of Greenland’s ice could occur.

“However, there is a warming threshold that could be crossed in a few decades or less and, if exceeded long enough, the meltdown of Greenland would be irreversible,” Alley said, according to National Geographic.

The results of the new study into Greenland’s ice melt was originally published in the Proceedings of the National Academy of Sciences.

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