Ice shelves like the Larsen C are the floating ends of glaciers on land. He expects it to rotate around to the east before continuing north. Long says it may hit “pointy end first,” which could cause it to break apart more quickly, and ocean currents could force the rest of the iceberg to pirouette north past South Georgia. If it does that, it will get stuck, or it will rotate around,” says David Long, director of the center for remote sensing at Brigham Young University, a lab that tracks iceberg movements. “It’s getting very close to grounding, which means it will hit the underwater shelf. “I wouldn’t be surprised if a large piece breaks off and we name it A68d.”Ĭhunks of A68 have broken off in the past three years, named A68b and A68c. “There are little tiny bergs about a mile long spinning off of it,”” says Readinger. Readinger notes that it’s in warmer waters than can sustain it and it’s likely already beginning to break apart. The iceberg could screech to a halt on the shallow underwater shelf that surrounds the island and not collide with dry land. “The ocean there is about 500 feet deep and the berg is about there. “It probably can’t get any closer,” says Readinger. Throughout 2020, A68 chugged north and east, zigging and zagging and rotating occasionally-but advancing steadily closer to South Georgia. Icebergs the size of A68 are so massive and extend so deeply into the sea that it often takes a sizable current to propel it forward. Throughout 2019, it wandered north through Antarctica’s Weddell Sea until it was caught in the strong Antarctic Circumpolar Current, a counterclockwise ocean current that circles the continent. But in 2018 it began drifting north and rotated several times, according to tracking records from Brigham Young University. The A68 iceberg was born-a chunk of ice the size of Delaware with a mass of about 10 percent of the shelf itself.įor most of 2017, the berg didn’t move much. A large, deep crack appeared in 2010 and continued to grow until July 2017, when it broke off. The Larsen C is the next ice shelf in line and by far the largest of the three. The Larsen A ice shelf, near the northern tip of the peninsula, collapsed in 1995 its neighbor to the south, Larsen B, was caught on spectacular satellite images as it followed suit in 2002. The Antarctic Peninsula is one of the fastest warming regions on Earth, and the ice shelves along its eastern coast are breaking apart. He describes A68’s genesis as a natural event, but says given the warming climate, particularly in the region that spawned the berg, it could be “a taste of things to come.” Timeline of A68 “We don’t have that much scientific information for icebergs like this,” says Geraint Tarling, an ecologist for the British Antarctic Survey. Photograph by IceBridge Digital Mapping System As the iceberg moved into the Atlantic's warmer waters in 2020, it began to break apart, spawning smaller icebergs and slowly eroding. Scientists estimate the cliffs are nearly seven stories, about 100 feet, tall. ( Find out about how climate change is melting the Antarctic Peninsula.)Īn image of A68 from November 2017 shows the craggy, steep edges of the iceberg's borders. It had been slowly inching north until this year, when an ocean current quickly propelled it into the Southern Atlantic Ocean. The iceberg, labeled A68, broke off from the Larsen C ice shelf on the east coast of the Antarctic Peninsula in 2017. What was the largest iceberg on Earth is threatening to come to a halt soon in a pristine Antarctic wildlife sanctuary that’s home to penguins, seals, and a small population of endangered blue whales. It’s unclear whether the remainder of A68 and its siblings will become stuck there and cut South Georgia’s wildlife off from feeding grounds, but the chunks of ice are rapidly releasing freshwater into an ecosystem adapted to saltwater. Recent satellite images show that the icebergs are caught in a strong ocean current that seems likely to sweep the chunks of ice around the southern edge of the island and spin them north. Since the iceberg calved from the Larsen C ice shelf three years ago, it has lost two-thirds of its volume. On December 22, the front, pointed tip of the iceberg broke, producing 68-square-mile A68e and 252-square-mile A68f. On December 17, about 69 square miles broke from the iceberg, forming A68d. Update: As of today, the A68 iceberg, once the world’s largest, has lost significant chunks of ice and continues to break apart, satellite images show.
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