Science

Rapidly Melting Greenland Glacier Could Raise Sea Levels By 18 Inches

A giant glacier in northeast Greenland is melting so rapidly that it could increase global sea levels by more than 18 inches. If the glacier keeps melting at the same pace, we would see continuous sea level rise for decades to come. Zachariæ Isstrøm is one of the three main glaciers in the Northeast Greenland Ice Stream. It entered a phase of “accelerated retreat” in 2012.

Rapidly Melting Greenland Glacier Could Raise Sea Levels By 18 Inches

Zachariæ Isstrøm has detached from the stabilizing sill

Findings of the NASA-funded study were published in the journal Science. Scientists found that the recede of the enormous Zachariæ Isstrøm tripled in 2012, speeding up by 125 meters every year until 2015, the most recent measurements. Global warming and hotter air have caused the glacier to detach from the stabilizing sill that anchors it to the coastline. The glacier is now crumbling into the North Atlantic Ocean.

Jeremie Mouginot of the University of California, Irvine said the northeast Greenland glacier is losing mass at a rate of 5 billion tons per year. Mouginot said the glacier had now become highly unstable. The melting will continue until to retreats to a ridge about 20 miles back, when the retreat may slow down a little. The giant glacier is now breaking up and calving chunks of icebergs into the ocean.

How scientists collected data on Greenland’s glacial ice

The study revealed that the area of the glacier’s floating shelf shrunk by a whopping 95% between 2002 and 2014. Zachariæ Isstrøm has an equally massive neighbor called Nioghalvfjerdsfjorden, which is also melting but at a slower rate. Together, these two glaciers have enough water to raise global sea levels by almost 40 inches.

To conduct the study, Mouginot and his colleagues used 40 years of data from satellites and aerial surveys, along with imagery from several international space agencies. Scientists used laser-profiling systems, sensitive radar sounder, optical images from space, and gravimeter to measure changes in the size, shape, and position of Greenland’s glacial ice. Mouginot said we no longer need to wonder. Now we know the results of global warming on polar glaciers.