Accelerating Cracks in Greenland's Ice Sheet Linked to Climate Change

Mon 3rd Feb, 2025

Recent research indicates that the cracks in Greenland's ice sheet are expanding at an alarming rate, underscoring the urgent implications of climate change on this critical component of the Earth's ecosystem. A study published in the journal Nature Geoscience reveals that the formation of glacial crevasses is accelerating, potentially leading to significant increases in ice loss.

The research team, led by experts from Durham University in the UK, analyzed over 8,000 three-dimensional surface maps of the ice sheet, utilizing high-resolution satellite imagery. Their findings indicate that from 2016 to 2021, the crevasses at the rapidly flowing edges of the ice sheet have not only grown larger but also deeper, a concerning trend that has occurred faster than previously documented.

Glacial crevasses are wedge-shaped fractures that form due to the uneven movement of glaciers. Ice flows at varying speeds, often faster at the surface and center than at the edges or in deeper layers, creating tension that causes the ice to crack. The study highlights that these dynamics are shifting as a result of climate change, with rising temperatures causing the ice to flow more rapidly, which in turn deepens and widens the existing fractures.

Significantly, the research shows that at the margins of the ice sheet, where large glaciers meet the ocean, the speed of glacial flow has increased. This acceleration has led to a notable rise in the volume of glacial crevasses, with some areas reporting an increase of up to 25% between 2016 and 2021, though with a margin of error of approximately ten percent.

While there has been some compensation for this increase due to a temporary slowdown in movement at the Sermeq Kujalleq (Southern Glacier), Greenland's fastest-flowing glacier, the overall trend suggests that the balance between the formation and closure of crevasses has shifted. The renewed acceleration of the Sermeq Kujalleq indicates a potential end to this equilibrium.

The lead researcher noted that an expectation of more crevasses forming in a warming world aligns with the observed phenomena, as glaciers respond to ocean warming by accelerating. Additionally, the meltwater that fills these crevasses can further penetrate the ice, exacerbating the issue.

The study provides critical insights into the significant increase in size and depth of crevasses at rapidly moving glaciers on the Greenland ice sheet, observed over short time frames of five years or less. The data reveals that not only are new crevasse fields expanding into the interior ice, but existing crevasse fields are also becoming larger and deeper.

Another researcher from the Byrd Polar & Climate Research Center at Ohio State University emphasized that as crevasses expand, they enhance the processes that increase the speed of ice movement, facilitating the influx of water and heat into the interior of the ice sheet. This can accelerate the calving of icebergs into the ocean, leading to a feedback loop that further intensifies ice loss.

According to the study, Greenland has already contributed approximately 14 millimeters to global sea level rise since 1992. If current trends persist, the meltwater from the ice sheet could raise global sea levels by up to 30 centimeters by 2100. In a worst-case scenario, the complete melting of Greenland's ice could result in a staggering seven-meter rise in sea levels.


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