A massive iceberg broke off from the George VI Ice Shelf in Antarctica in January, giving researchers a rare opportunity to observe a part of the planet never before seen by humans.
Coincidentally, a team of researchers from the Schmidt Ocean Institute in California, U.S., happened to be nearby when the ice spanning 510 square kilometers (197 square miles) calved, so the team quickly shifted gears and seized the opportunity to explore the newly exposed seafloor.
“Serendipitous moments are part of the excitement of research at sea – they offer the chance to be the first to witness the untouched beauty of our world,” Jyotika Virmani, executive director of Schmidt Ocean Institute, said in a press release.
With the ice gone, the team used remotely operated vehicles to explore the seafloor over eight days, reaching depths of up to 1,300 meters (4,265 feet), Patricia Esquete, a deep-sea ecologist with the University of Aveiro, Portugal, told Mongabay in a phone call.
The newly exposed area previously sat beneath a sheet of ice 150 m (492 ft) thick, so “we were expecting quite an impoverished ecosystem because it’s not receiving food from the surface, like in a normal deep-sea setting in which you have photosynthesis happening in the surface,” Esquete said.
What they found instead was a rich community of fish, coral, octopus, sea spiders, anemones and sponges, perhaps hundreds of years old. They suspect deep ocean currents are delivering the nutrients that sustain life beneath the ice shelf.
“We found a really well-established ecosystem,” Esquete said. The team recovered many samples for further study, particularly those they suspect are new to science. “We have several new species, that’s for sure — of fish, of crustaceans [and] polychaete worms,” she said.
Esquete suspects that the potentially new-to-science species aren’t unique to seafloors beneath ice shelves. It’s more likely they are found across the region but scientists haven’t extensively explored the harsh, frigid, Antarctic seafloor before now. “It’s just very little-explored in general,” she said.
The team also collected data on topography that revealed sharp, sometimes vertical, cliffs near steep depressions, 1,300 meters deep. “So, if you imagine, say, Yosemite National Park [in California], put it underwater,” Sasha Montelli, co-chief scientist on the expedition and a geophysicist with University College London, told Mongabay.
As climate change accelerates the melting of Antarctica’s ice sheets, calving events like this one are expected to become more frequent. Montelli said the researchers plan to return to the site to track changes in ocean currents and seafloor ecosystems, so they can develop models that can project “how ice loss from Antarctica is going to evolve under different climate change scenarios.”
Banner image: An octopus rests on the seafloor 1,150 meters (3,773 feet) deep, in the Bellingshausen Sea off Antarctica. Image courtesy of the Schmidt Ocean Institute. / Schmidt Ocean Institute