Antarctic Iceberg Mission Thwarted by … Ice

first_img When one of the largest-ever icebergs broke free from the Larsen C Ice Shelf last year, scientists welcomed the chance to study the newly exposed ocean and underlying seabed—covered for 120,000 years.Like a teenager slamming their bedroom door in defiance, the 2,300-square-mile A68 iceberg’s calving is normal, if not dramatic.Researchers are mostly interested in its impact on the stability of the remaining Antarctic ice shelf. Further north on the peninsula, the Larsen A and B ledges collapsed in 1995 and 2002, respectively.AdChoices广告“This resulted in the dramatic acceleration of the glaciers behind them, with larger volumes of ice entering the ocean and contributing to sea-level rise,” according to glaciologist David Vaughan, Director of Science at the British Antarctic Survey (BAS). “If Larsen C now starts to retreat significantly and eventually collapses, then we will see another contribution to sea level rise.”A team of scientists set off last month on a mission to investigate the hidden ecosystem. But their three-week tour aboard BAS research ship RRS James Clark Ross was cut short—ironically, by sea ice.“We knew that getting through the sea ice to reach Larsen C would be difficult,” marine biologist and principal investigator Katrin Linse, of the British Antarctic Survey, said in a statement. “Naturally, we are disappointed not to get there but safety must come first.”Chunks up to 16 feet thick stonewalled the boat, which moved just five miles in 24 hours. On Feb. 28, the captain made the “difficult decision” to end the trip.“Mother Nature has not been kind to us on our mission,” Linse said.Luckily, they had a Plan B: Head north to untouched areas to sample the benthic biodiversity. (That is, the ecological region at the lowest level of a body of water.)The international team spent the final week of their cruise collecting seafloor animals, microbes, plankton, sediments, and water samples, as well as marine mammals and birds that might have moved into the area.Antarctic brittle star (via British Antarctic Survey)These findings will provide a better picture of life under the ice shelf and allow researchers to track changes to the ecosystem.Scientists have long debated the cause of Larsen Ice Shelf thinning—climate or ocean change?—but knew the splintering was imminent, based on satellite imagery.“Larsen C itself might be a result of climate change, but in other ice shelves we see cracks forming, which we don’t believe have any connection to climate change,” Vaughan said.Earth’s southernmost continent is in no immediate danger, though.“We see no obvious signal that climate warming is causing the whole of Antarctica to break up,” he continued. “However, around the Antarctic Peninsula, where we saw several decades of warming through the latter half of the 20th century, we have seen these ice shelves collapsing and ice loss increasing.” Boaty McBoatface Makes Major Climate Change DiscoveryCyborg Seals Help Explain Mysterious Antarctic Ice Holes Stay on targetcenter_img Let us know what you like about Geek by taking our survey.last_img read more

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