Beneath a giant iceberg, a whole ecosystem never seen before. Iceberg A-84 broke off from Antarctica and revealed a thriving community of sea creatures underneath. Now, researchers are curious as to how these species have survived. Fracturing icebergs are only going to become more common as climate change worsens, metaphorically thawing a whole field of research in the process.
Breaking the ice
An iceberg the size of Chicago broke away from the George VI Ice Shelf on January 13, 2025. This allowed researchers aboard the Schmidt Ocean Institute’s R/V Falkor (too) to investigate what lived on the seafloor under the broken piece. “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,” Dr. Patricia Esquete, the expedition co-chief scientist, said in a statement.
The experts identified more than 70 new species, “including squat lobsters and marine snails that were completely new to science,” said The Washington Post. “There was a sense of going into a complete unknown,” Sasha Montelli of University College London, also a co-chief scientist, said to Scientific American. “We thought we might see some life there, but it was really surprising to see the degree to which life was thriving in such a hostile environment. And it wasn’t just existing there but had apparently been sustained for a very long time.” Based on the size of the communities of species, the researchers estimate that the ecosystem may have been around for decades or even hundreds of years. Lab research is still required to determine whether any of the species are new.
4,265 feet under the sea
To discover the marine ecosystem, the researchers used a remotely operated vehicle, ROV SuBastian, to explore 4,265 feet below the surface of the ocean. “Normally, deep-sea ecosystems get their nutrients from the sea surface, which sprinkle down toward the seafloor,” said National Geographic. “But this area was covered by a 500-foot-thick icy roof for an interminable amount of time, meaning that these critters must be getting their nutrients another way.” The question remains as to how a thriving underwater ecosystem can exist in such conditions.
One of the theories is that “these lifeforms may derive their energy from ocean currents, which sweep nutrients beneath the ice sheet to sustain the ecosystem,” said IFL Science. This is still an active area of scientific research. What is even more uncertain is “how this vibrant ecosystem will fare now that the iceberg has broken away,” said Scientific American. “Many deep-sea dwellers are adapted to unchanging conditions found in their environment, so they are highly sensitive to even small environmental shifts.”
Warming temperatures due to climate change is causing the Antarctic ice sheet to melt, making it a “major contributor to sea level rise worldwide,” Montelli said in the statement. “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.”