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Thwaites Glacier’s Rapid Fracture Accelerates Antarctic Ice Loss, New Study Reveals
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A new study detailing the accelerating disintegration of the Thwaites Glacier in West Antarctica raises urgent concerns about global sea level rise. Researchers have documented a dramatic increase in cracking across the glacier’s ice shelf over the past two decades, a process that is destabilizing the region and accelerating the flow of ice into the ocean.
The “Doomsday Glacier” Under Strain
Known as the “Doomsday Glacier” due to its potential for catastrophic sea level rise, the Thwaites Glacier is one of the most rapidly changing features on Earth.Its future evolution remains a critical unknown in predicting the extent of future coastal flooding. The eastern ice shelf of Thwaites is anchored at its northern end by a submerged ridge, but this natural support system is rapidly failing.
two Decades of Cracking: A detailed Record
A comprehensive analysis of observational data from 2002 to 2022, conducted by researchers at the center for Earth Observation and Science at the University of Manitoba, Canada, and part of the International Thwaites Glacier collaboration (ITGC), reveals a disturbing trend. The study meticulously tracks the formation and propagation of cracks within the ice shelf’s shear zone. As these fissures expand, the connection between the ice shelf and the supporting mid-ocean ridge weakens, leading to a faster flow of ice from the glacier’s interior.
Crack Growth in Four Phases
The weakening of the ice shelf didn’t happen all at once, but unfolded in four distinct phases characterized by two stages of crack growth. Initially, long cracks appeared, aligning with the direction of ice flow and extending eastward across the shelf – some exceeding 8 kilometers in length. Afterward, a proliferation of shorter, cross-flow cracks, less than 2 kilometers long, emerged, effectively doubling the total length of the fissures.
Satellite imagery analysis confirms this accelerating fracture. The total length of cracks increased from approximately 165 kilometers in 2002 to around 336 kilometers in 2021. Together, the average crack length decreased from 3.2 kilometers to 1.5 kilometers, indicating a meaningful increase in the number of smaller cracks. These changes reflect a fundamental shift in the stress state of the ice shelf, altering how forces interact within its structure.
From Stabilization to Destabilization
between 2002 and 2006, the ice shelf experienced a period of acceleration due to the pull of nearby currents, which initially generated compressive stress that stabilized the anchorage point. However, after 2007, the shear zone between the shelf and the Western ice tongue collapsed.This collapse concentrated stress around the anchorage point, triggering the formation of larger cracks.Since 2017, these cracks have fully penetrated the ice shelf, effectively severing its connection to the anchoring ridge. Researchers state this has dramatically accelerated the upstream flow of ice, transforming the anchorage from a stabilizing feature into a destabilizing one.
A hazardous Feedback Loop
Perhaps the most alarming finding of the study is the identification of a positive feedback loop. Cracks accelerate the flow of ice, and that increased speed, in turn, generates new cracks. This self-reinforcing cycle was directly observed through
