Greenland's ice sheet is cracking and literally falling apart at a very alarming rate

Greenland’s Ice Sheet is cracking open at the seams, literally falling apart at speeds indicative of the brutal and accelerating impact of global climate change. In just five years, 930 million cubic meters of crevasses opened up in the Greenland ice sheet.

A recent, large-scale study from the University of Florida highlights how this vast, frozen expanse – the world’s second-largest ice sheet – is fracturing faster than expected.

The findings suggest that the ice sheet’s response to warming is intensifying. This essential discovery was born out of an effective collaboration with scientists from Durham University, UK.

Their detailed analysis of the ice sheet over the critical period between 2016 and 2021 revealed that the crevasses – wedge-shaped fractures in the ice – have increased alarmingly in both size and depth.

These ice fractures typically appear where the ice starts to flow faster.

The data revealed that the ice sheet’s response to climate changes is accelerating the formation of broader and deeper crevasses.

Cracks in Greenland’s ice sheet

The researchers point out that these rapid changes observed in Greenland’s ice sheet crevasses can, in turn, speed up the mechanisms that have resulted in the ever-quickening pace of this devastating ice loss.

The team hopes their findings will help fellow scientists incorporate the consequences of ice damage and crevassing into future predictions related to the behavior of the Greenland Ice Sheet.

Throughout the years, Greenland has been one of the most important contributors to the rise of sea levels. Since 1992, about 14mm of sea level rise can be attributed to ice flow off Greenland.

This is a direct result of the melting of the ice surface, which is related to the presence of warmer air and sea temperatures, along with the increased flow of ice into the ocean.

Why Greenland’s ice sheet is important

As this massive ice sheet loses ice, it adds freshwater to the ocean, causing sea levels to rise. Even small increases can lead to bigger storm surges, more coastal flooding, and make some places unlivable.

Millions of people in low-lying areas could be forced to relocate, and cities like New York and Miami could see major impacts.

The melting also speeds up itself – less ice means less sunlight is reflected, which warms the planet even more.

If all the ice sheet in Greenland were to melt, we could see a potential rise of seven meters (23 feet) in the sea levels around the world.

But, as bad as that sounds, it’s not just about sea levels. Greenland’s ice melt messes with ocean currents that help regulate the climate.

The freshwater pouring into the Atlantic can slow down the Atlantic Meridional Overturning Circulation (AMOC), a system that moves warm water from the tropics toward Europe.

If that weakens, Europe could face colder winters, hurricanes could get stronger, and weather patterns worldwide could shift in unpredictable ways.

Satellite imagery of Greenland’s ice sheet

In their innovative study, the researchers from Durham University used over 8,000 3-D surface maps, that had been created using high-resolution satellite imagery.

“You can’t do it in person, because crevasses are dangerous. It’s hard to study by hand using satellite data. Automated approaches are needed to determine this at an ice-sheet scale,” said Emma MacKie, Ph.D., a professor of geological sciences at the University of Florida, co-author of the study, and expert in machine learning techniques.

This allowed them to identify cracks on the ice surface and to track the evolution of crevasses across Greenland during the period of 2016 to 2021.

Their findings showed that, in the areas where large glaciers meet the sea, accelerations in glacier flow were associated with significant increases in the volume of crevasses.

A fascinating discovery was that the overall change in crevasses across the entire ice sheet ultimately balanced out due to a temporary slowdown in movement at Sermeq Kujalleq, the fastest-flowing glacier in Greenland.

Nevertheless, the flow speed of Sermeq Kujalleq has started increasing again, indicating that the period of balance between crevasse growth and closure might be over.

Higher temperatures = faster ice melt

“In a warming world, we would expect to see more crevasses forming,” shared study lead author Dr. Tom Chudley, a Leverhulme Early Career Fellow in the Department of Geography, Durham University, UK.

“This is because glaciers are accelerating in response to warmer ocean temperatures, and because meltwater filling crevasses can force fractures deeper into the ice. However, until now we haven’t had the data to show where and how fast this is happening across the entirety of the Greenland Ice Sheet.”

With this dataset, the scientists can see that it’s not just that crevasse fields are extending into the ice sheet, as previously observed.

Instead, the current state of Greenland’s ice sheet change is dominated by existing crevasse fields getting larger and deeper.

Notably, these developments have the potential to expedite the loss of ice from Greenland.

“Crevasses can induce accelerated ice flow, leading to more crevassing. So there are these potential positive feedback loops caused by crevassing,” MacKie said. “This mechanism should be considered in Greenland ice sheet models that we’re using to project future sea level rise.”

It’s a domino effect that could drive the loss of ice from Greenland at a much faster pace, pointed out study co-author, Professor Ian Howat, who is Director of the Byrd Polar & Climate Research Center at The Ohio State University.

Discerning eye on the Arctic

The high-resolution imagery for the research was provided by the National Geospatial-Intelligence Agency (NGA) and National Science Foundation (NSF) public-private initiative, ArticDEM project.

“The ArcticDEM project will continue to provide high-resolution Digital Elevation Models until at least 2032. This will allow us to monitor glaciers in Greenland and across the wider Arctic as they continue to respond to climate change,” Professor Howat added.

This invaluable information will reveal areas that are experiencing faster rates of warming than any other place in Earth, preparing us with information we need to mitigate the effect of climate change and protect the future of our planet.

The full study was published in the journal Nature.

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