Ice Sheets in Greenland Cracking Away With Huge Chunks at an Alarming Rate Has Scientists Worried

We know that the polar region, specifically the ice sheets in Greenland, covers 0.7 million cubic miles and extends over 656,000 square miles, according to the National Snow and Ice Data Center. However, the ice sheets have started to form huge cracks in them, moving apart in massive fragments over five years as seen after the latest 3D mapping of the region, stated Live Science. The scientist did not anticipate the icy landmass to crack away in huge chunks at an alarming rate. 

These crevices lie around the edges of the vast ice sheets where the ice chips away and melts into the ocean. The inland glaciers also receive meltwater and heat in this process. The researchers predicted that this might trigger a domino effect where the polar ice would start melting at an even faster pace and the sea level would rise to dangerous heights. The melting of the ice sheet from Greenland has been causing the sea level to rise 0.6 inches per year since the 1990s.

"Melting causes the Greenland Ice Sheet's glaciers to flow faster down slopes and valleys. This, in turn, stretches the ice sheet so much that it cracks open," Thomas Chudley, a glaciologist at Durham University in the U.K. and the lead author of a new study of Greenland's crevasses, said in a video. "As the ice sheet accelerates, we would expect to see more crevasses and deeper crevasses. So, our research aimed to look at where these crevasses were and how they were changing in the 21st century." Chudley and his colleagues studied the crevasses in Greenland by looking through more than 8,000 3D maps of the island's surface.

The data was collected from the Polar Geospatial Center at the University of Minnesota, which creates 3D maps from high-resolution satellite images. The results of their study were published in the journal, Nature Geoscience, revealing the fissures in the ice sheet that was growing by 25% over the past five years. The team of experts compared the size, shape, and distribution of the cracks on the ice sheets from 2016 to the ones formed in 2021 to see how the icy surface was responding to global warming.

"Where the ice sheet has been accelerating, we are seeing more, and we are seeing deeper crevasses," Chudley said. "This is especially true in the areas of the ice sheet that are exposed to the ocean and that have seen significant warming from the ocean since the 1990s." However, a glacier in Greenland called Jakobshavn largely benefitted from the molten ice at one point.

Jakobshavn happens to be the fastest-flowing glacier on Earth but between 2016 to 2018, the influx of cold water from the North Atlantic Ocean slowed the glacial flow and chunks of ice piled into the glacier. As a result, the Greenland Ice Sheet shrank by 4% between 2016 and 2021. Chudley predicted that we might see sea levels rise from 10 or 20 meters due to the molten ice from the region shortly.

"This slowdown and the closure of crevasses that it caused single-handedly outweighed the increase in crevasses across the rest of the ice sheet," Chudley mentioned. "But in 2018, Jakobshavn began moving at full throttle again. This means the glacier likely won't compensate for future increases in crevasse size elsewhere." "As crevasses grow, they feed the mechanisms that make the ice sheet's glaciers move faster," the study's co-author Ian Howat, a professor and glaciologist at Ohio State University, said in a statement. "These processes can in turn speed up ice flow and lead to the formation of more and deeper crevasses — a domino effect that could drive the loss of ice from Greenland at a faster pace."