Ted Scambos, a research glaciologist at the University of Colorado at Boulder, said the Ronne and another vast ice shelf, the Ross, have 'behaved in a stable, quasi-periodic fashion' over the past century or more.īecause the ice was already floating in the sea before dislodging from the coast, its break-away does not raise ocean levels, he said email. READ MORE: Giant iceberg on course to hit south Atlantic penguin colonyĪ68a, which was 160 kilometres long and 48 kilometres across, broke up before it could cause any damage to the abundant wildlife in the British Overseas Territory of South Georgia. The iceberg, known as A68a, had also broken off from the Larsen Ice Shelf, which has warmed faster than any other part of Earth's southernmost continent. In November last year, what was then the world's largest iceberg appeared to be on a collision course with a remote South Atlantic island home to thousands of penguins and seals, threatening to impede their ability to gather food. It takes the place as the world's largest from the A-23A iceberg – approximately 3,880 square kilometres in size – which is also in the Weddell Sea. The berg, which broke off the western side of the Ronne Ice Shelf, was originally spotted by the British Antarctic Survey and confirmed using images from the Copernicus satellite. This segment aired on February 17, 2020.New giant #iceberg breaking away from the Ronne Ice Shelf 13-05-2021 roughly 160 km x 25 km satellite image from #Sentinel1 /LmacupcuUW- Keith Makinson May 13, 2021 But the ice shelf acts as a wall, so when it melts, she says, the wall crumbles and lets melting inland ice flow into the ocean.Ĭristina Kim produced this story and edited it for broadcast with Todd Mundt. The melting ice shelf is not going to directly contribute to sea-level rise, she says. When the ocean warms, the glacier’s ice shelf starts melting off because 90% of a floating glacier is in the ocean. These massive calving events are a result of two climate change-related factors - rising air temperature and ocean temperature, she says. “So it's much more likely to calve in the future.” “So it has nothing to buttress up against at this point,” she says. The glacier was once buttressed against a tributary ice flow, she says, but after a calving event in 2018, Pine Island “lost contact” with the tributary ice, meaning it now has “less support” and is susceptible to cracks. Scientists are worried about the future of Pine Island Glacier because its ice is retreating at an accelerated rate, exceeding 35 feet per day, she says.

Small pieces have now broken off from the original iceberg. 9 - that’s roughly three times the size of San Francisco. “So many towns and cities are almost at sea level at this point.”īanwell says 120 square miles of ice broke off Pine Island on Feb. “Rising sea levels - even just by a few centimeters, even a few millimeters - is going to start flooding low lying communities worldwide,” she says. The glacier is also the biggest single contributor to global sea-level rise of any glacier on Earth, she says. Pine Island Glacier is important in particular because it has the ability to raise global sea levels by four feet in total, she says. But now, calving events occur “almost annually” on Pine Island, she says.

In the past, Pine Island would calve every four to six years, glaciologist Alison Banwell says. The loss of large ice chunks, known as calving, is a routine process that happens to every glacier. Some parts of the content recently experienced record-high temperatures of nearly 70 degrees Fahrenheit. The glacier, known as Pine Island, is considered one of the fastest retreating glaciers in Antarctica, where the climate is changing rapidly. This month, an iceberg nearly the size of Atlanta broke off in Antarctica. (Courtesy of NASA) This article is more than 2 years old. Pine Island Glacier in Antarctica spawns new iceberg on February 11, 2020.

Iceberg breaks off