How Antarctic Ices Become Unstable

Climate change and global warming are already beginning to cause ill-effects around the planet, from disrupting ecosystems to causing more volcanic eruptions and making soils arid. But probably these phenomena bring about their worse effects in polar regions. While, in the North, they heat up the Arctic and Greenland, in the South, they cause more and more ice spreads, such as the West Antarctic Ice Sheet (WAIS), to melt, and further contribute to their ill-effects. In a new study, researchers looked at how these trends could make things even worse in the near future, ScienceDaily reports.

“The volume of ice locked up in the West Antarctic Ice Sheet is equivalent to a sea level rise of around 3.3 meters. Our model shows how instability in the grounding line, caused by gradual climatic changes, has the potential to reach a 'tipping point' where disintegration of the ice sheet could occur,” Oxford University Department of Earth Sciences Professor Dr. Richard Katz says. He is also an author of the new report, entitled “Stability of ice sheet grounding lines,” which is published in the latest issue of the respected scientific journal Proceedings of the Royal Society A.

Together with researchers from the Cambridge University, the Oxford team compiled a new model, which accounts for the changes that appear in the “grounding line.” This concept refers to the area where a floating ice sheet connects with the land. The scientists believe that changes in this line trigger the most severe and important effects, as far as an ice sheet's ultimate faith goes. This simulation is currently relatively simple and straightforward, the British collaboration says, but plans are to further develop it in the near future.

The most important additions that the group wants to implement include the modeling of individual ice streams that exist at the grounding line, as well as the paths that sheets such as the WAIS take on the slopes of rock and sediments that separate their ground-based section from their floating one. “Global climate models often assume that, as the world warms, ice sheets will melt at a steady rate, leading to gradual rises in sea level – but ice sheets are much more complex structures than this. 'We need to do a lot more work to build better models of how ice sheets behave in the real world. Only then can we start to predict how this behavior might change in the future as the climate changes,” Katz explains.