Northern Greenland's Huge Glaciers At Risk Due To Warming Oceans, Study Finds

A study has found out that the huge glaciers in Northern Greenland were at risk due to warming oceans.

Experts said that the glaciers of North Greenland were hosting enough ice to raise sea level by 2.1 m, and have long considered to be stable.

They said that this part of Greenland is buttressed by the last remaining ice shelves of the ice sheet.

Ice Shelves

In the study, experts revealed that since 1978, ice shelves in North Greenland have lost more than 35% of their total volume, with three of them collapsing completely.

For the floating ice shelves that have actually remained, scientists observed a widespread increase in ice shelf mass losses that are dominated by enhanced basal melting rates.

It has been recorded that between 2000 and 2020, there was a widespread increase in basal melt rates that closely follows a rise in the ocean temperature.

Due to this, the glaciers have shown a direct dynamical response to ice shelf changes with retreating grounding lines and increased ice discharge.

Based on recent studies, the intrusion of warm Atlantic water has been responsible for widespread enhanced calving rates at marine terminating glaciers around Greenland.

They said that mass losses increased more or less simultaneously in the northwest, southeast and central west part of the ice sheet during the 80s and the 90s.

However, glaciers in North Greenland only started to be out of balance after 2000 and this phenomenon could be attributed in changes in the floating extension or the ice shelves of a couple of glaciers.

Meanwhile, in 2018, the mass losses of these glaciers due to ice discharge remained moderate compared to the other sectors of the Greenland ice sheet.

If the glaciers that are situated in North Greenland lose the buttressing provided by ice shelves, the increase in discharge could rival the largest contributors to Greenland ice mass loss, according to experts.

Melting

The study pointed out that the observed increase in melting coincides with a distinct rise in ocean potential temperature, suggesting a strong oceanic control on ice shelves changes.

Earlier observations of the changes in ice thicknesses and basal melting in the 1990-2000 would be needed to further detail the processes and exact timing of events that have led to the collapse of the ice shelves.

Scientists noted that for the remaining ice shelves, basal melting rivals the highest rates observed in the Amundsen sea Embayment of Antarctica.

The observed increase in melting coincides with a distinct rise in ocean potential temperature, suggesting a strong oceanic control on ice shelves changes.

Experts warned that if the oceans continue to warm, it could permanently weaken the ice shelves,

Further, in a certain timescale, the ice shelves could even collapse, which could have significant consequences on the contribution of the Greenland ice sheet to sea level rise.

It was said that between 2006 and 2018, the melting of Greenland's ice sheet contributed to more than 17 percent of observed sea level rise.