Punta Arenas, Chile - March 21, 2025 An international team on board Schmidt Ocean Institute’s R/V Falkor (too) working in the Bellingshausen Sea rapidly pivoted their research plans to study an area that was, until last month, covered by ice. On January 13, 2025, an iceberg the size of Chicago, named A-84, broke away from the George VI Ice Shelf, one of the massive floating glaciers attached to the Antarctic Peninsula ice sheet. The team reached the newly exposed seafloor on January 25 and became the first to investigate an area that had never before been accessible to humans. The expedition was the first detailed, comprehensive, and interdisciplinary study of the geology, physical oceanography, and biology beneath such a large area once covered by a floating ice shelf. The ice that calved was approximately 510 square kilometers (209 square miles), revealing an equivalent area of seafloor. “We seized upon the moment, changed our expedition plan, and went for it so we could look at what was happening in the depths below,” said expedition co-chief scientist Dr. Patricia Esquete of the Centre for Environmental and Marine Studies (CESAM) and the Department of Biology (DBio) at the University of Aveiro, Portugal. “We didn’t expect to find such a beautiful, thriving ecosystem.” Using Schmidt Ocean Institute’s remotely operated vehicle, ROV SuBastian, the team observed the deep seafloor for eight days and found flourishing ecosystems at depths as great as 1300 meters. Their observations include large corals and sponges supporting an array of animal life, including icefish, giant sea spiders, and octopus. The team was surprised by the significant biomass and biodiversity of the ecosystems and suspect they have discovered several new species. Deep-sea ecosystems typically rely on nutrients from the surface, but these Antarctic ecosystems have been covered by 150-meter-thick ice for centuries, cut off from surface nutrients. The team hypothesizes that ocean currents sustain life beneath the ice sheet. The newly exposed seafloor also allowed the team to gather critical data on the past behavior of the Antarctic ice sheet, which has been shrinking due to climate change. “The ice loss from the Antarctic Ice Sheet is a major contributor to sea level rise worldwide,” said expedition co-chief scientist Sasha Montelli of University College London (UCL). In addition to collecting samples, the team deployed gliders to study the impacts of glacial meltwater. Preliminary data suggest high biological productivity and a strong meltwater flow from the George IV ice shelf. The expedition was part of Challenger 150, a global cooperative focused on deep-sea research.