New data and seafloor images published Monday in Nature Geoscience found that the Florida-sized ice behemoth experienced a “rapid retreat” over the past two centuries — and predicted that history may repeat itself in the near future. A total loss of the glacier and surrounding ice basins could raise sea levels by three to 10 feet, the researchers said. Thwaites is already in ‘collapse’ when viewed on geological timescales, but new images of the seafloor suggest it once retreated at twice the rate – at a rate of 2.1km per year – in less than six months within the previous two centuries. “Thwaites is really holding on today,” said Robert Larter, a marine geophysicist with the British Antarctic Survey and co-author of the study, in a press release. “We should expect to see large changes on small time scales in the future – even from one year to the next – when the glacier retreats past a shallow ridge in its bed,” he continued. By analyzing ridges on the sea floor, scientists were able to map the movements of the glacier as it surged with the tide. This “map” showed that the rapid change occurred when the Thwaites Front detached from the trough ridge that held it ashore. Thwaites currently releases 50 billion tons of ice into the water each year, accounting for 4 percent of global sea-level rise, according to the National Snow and Ice Data Center. However, this study and recent ones like it suggest that this pace may be changing quickly. For example, satellite images from late 2021 found that a critical ice shelf holding Thwaites Glacier together could break off within the next few years. Although scientists once believed that the ice sheets were slow to respond, it’s becoming clear that’s not true, Alastair Graham, a marine geophysicist at the University of South Florida’s College of Marine Science and an author of the study, said in the release. “Just a small kick to Thwaites could lead to a big response,” he said. SHARE:
