Scientists detect ice piracy in Antarctica
New scientific research, published in The Cryosphere, shows that glaciers in the Pope, Smith, and Kohler regions of West Antarctica continue to accelerate, with some even shifting their flow direction. These changes could have long-term impacts on global sea levels, Kazinform News Agency correspondent reports.
Speeding up and slowing down
Satellite observations from 2005 to 2022 have revealed significant shifts in the movement speed of eight major glaciers. Seven of them have sped up at their grounding lines, (where ice transitions from grounded ice sheet to freely floating ice shelf) with the fastest increase (87%) recorded at Smith West Glacier. In contrast, Kohler West Glacier has slowed by 10%.
Scientists believe this slowdown is linked to a decrease in ice thickness, which reduces pressure and, consequently, slows the glacier’s movement. However, the overall trend for the region is one of acceleration, especially in the central area, where Kohler East, Smith West, and Smith East glaciers are now moving at speeds exceeding 1,200 meters per year.
Speed changes are not linear: glaciers accelerated 14% during 2005–2010, slowed 4% by 2013, then sped up again, likely tied to ocean heat fluctuations.
Shifting ice flows
One unexpected discovery was the change in ice flow direction. Researchers observed "ice piracy" - where Kohler West Glacier is losing ice to its faster-moving neighbor, Kohler East Glacier. This occurs because Kohler East is thinning more rapidly, creating a steeper slope that literally pulls ice flow away from Kohler West.
In addition, the boundary between the Dotson and Crosson ice shelves has shifted eastward. This has increased the flow of ice toward Dotson, which could help stabilize it, while Crosson continues to break apart.
Impacts on ice sheets
Since 2005, the Crosson Ice Shelf has retreated by about 60 kilometers, with its eastern section suffering extensive damage. A 12-kilometer-long rift has formed and continues to grow. The rift has advanced 3 km since 2015 (now 5 km from Bear Island). If it reaches Bear Island, a 4 km² iceberg could break off.
Scientists note that these changes are part of a longer-term process likely linked to ocean warming and shifting winds over the continental shelf. While there is still no conclusive evidence of an irreversible collapse of these glaciers, the trends are concerning and warrant close monitoring.
Earlier, Kazinform News Agency reported that two-thirds of global warming is caused by world’s richest 10%.