In January 2025, researchers on the Schmidt Ocean Institute’s R/V Falkor (too) had to divert their plans after an iceberg roughly the size of Chicago broke away from the George VI Ice Shelf, a floating glacier that had been attached to the Antarctic Peninsula ice sheet.
As the iceberg broke away, it exposed an area of seabed previously unseen by humans. There, they found it teeming with a variety of sea life.
An Iceberg the Size of the Windy City
The iceberg, named A-84 by the U.S. National Ice Center, is about 19 miles long and 11 miles wide. The area is about 209 square miles, which is close to Chicago’s 230 square miles. As A-84 broke away from the George VI Ice Shelf, it exposed an area of sea bed equal in size to the iceberg.
After getting word that A-84 had separated from the ice shelf, the international research team on R/V Falkor (too) changed course and headed for the now exposed sea bed. What they found was astonishing.
“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 Patricia Esquete of the Centre for Environmental and Marine Studies (CESAM) and the Department of Biology (DBio) at the University of Aveiro, Portugal, in a press release.
“We didn’t expect to find such a beautiful, thriving ecosystem. Based on the size of the animals, the communities we observed have been there for decades, maybe even hundreds of years,” Esquete added in a press release.
Read More: Ice Quakes Cause Glacial Ice to Flow Toward the Ocean
The First Glimpse at a Thriving Ecosystem
Once on location, the research team used Schmidt Ocean Institute’s remotely operated vehicle, ROV SuBastian, to search the sea floor. After eight days, the team observed various sea life, including corals, octopuses, giant sea spiders, and sponges. Some creatures even dwelled at depths of over 4,000 feet.
What surprised the research team the most was how much life was living beneath the ice sheet. In open ocean settings, deep-sea environments usually depend on nutrients that fall from the surface. However, this ecosystem has been covered by an ice sheet that’s about 500 feet thick for centuries. The team believes that ocean currents must be bringing nutrients into this ecosystem, though more research is needed.
The findings help researchers better understand how life thrives underneath floating ice shelves, as little information exists on the subject. According to the press release, this expedition is the first to use an ROV to observe marine life in this setting, and it’s believed that they may have encountered several new species, along with several already known to science.
A Shifting Climate
The data collected from this environment also helps the international research team study the Antarctic ice sheet’s past behavior as it 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 Sasha Montelli of University College London (UCL), U.K., also a 2019 Schmidt Science Fellow, in a press release. “Our work is critical for providing longer-term context of these recent changes, improving our ability to make projections of future change — projections that can inform actionable policies. We will undoubtedly make new discoveries as we continue to analyze this vital data.”
Using “autonomous underwater vehicles” known as gliders, the team also analyzed glacial meltwater from the George VI ice shelf and how it would impact the physical and chemical properties of the area. They found that the George VI ice shelf had a strong meltwater flow and high biological productivity.
Read More: Iceberg Versus Island in the South Atlantic Ocean
Article Sources
Our writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:
NASA Earth Observatory. New Antarctic Iceberg Speeds Off
Britannica. Chicago
A graduate of UW-Whitewater, Monica Cull wrote for several organizations, including one that focused on bees and the natural world, before coming to Discover Magazine. Her current work also appears on her travel blog and Common State Magazine. Her love of science came from watching PBS shows as a kid with her mom and spending too much time binging Doctor Who.
