9
A tower block of ice has split off from a glacier less than a mile away from a ship on which Sky News is filming scientists as they track the impact of climate change.The huge slab, at least 40 metres high and weighing thousands of tonnes, toppled from the William Glacier on Anvers Island, Antarctica.Dramatic footage filmed in the early hours by a crew mate on our British Antarctic Survey ship, the James Clark Ross, shows the berg sliding into the fjord, then spinning almost in slow motion as water and ice cascade down its sides.Image:The huge slab was at least 40 metres high.
Pic: John O'Duffy/British Antarctic SurveyThe birth of the iceberg was part of a collapse that stretched half a mile across the glacier front and lasted for several minutes.Chief officer Simon Wallace was watching on the bridge.He told Sky News: "The whole world started moving.
It was hard to take in just how much was going on at the same time."The front of the glacier just broke.
It was like a sandcastle in the face of the sea.
There was a distinct shift to the right and then it seemed to disappear."All of a sudden we were confronted by what seemed like a wall of water making its way towards us, but it was the iceberg surfacing a bit like a submarine and rotating at the same time."It was incredibly awe-inspiring."Our ship, which was barely a mile away at the time, hurriedly left the bay because of the risk of an even more catastrophic event triggering a tsunami.But a few hours later we returned.What had been open water was now a carpet of ice covering more than five square miles of the bay, underlining the vast volume of the glacier that had been lost in the event.Icebergs were still shattering into smaller pieces and capsizing as they found a new centre of gravity.Meanwhile, thunderous booms on the glacier strongly suggested that the ice was unstable and liable to calve further.Calving is when large chunks of ice split off from the end of a glacier.The William Glacier in Borgen Bay has retreated almost a mile in 20 years, and is one of three areas being studied by scientists over three years as part of the joint UK-Chile 'Icebergs' expedition.The glacier rests on the bottom of the fjord, 170m below the surface.Kate Retallick from the University of Bangor, who is mapping the seafloor and the underwater cliff of the glacier front, said: "It's amazing to have witnessed such a big calving event."The bit of the glacier you are seeing above the surface - the 40-odd metres - that has been released.
But all the stuff below has also come up.Scientists brave the cold to study the threat to Antarctica"These icebergs aren't just the size of houses, they are the size of blocks of houses and blocks of flats.
It's not insignificant at all."Antarctica has lost three trillion tonnes of ice over the last 25 years - half of it in the last five.The Intergovernmental Panel on Climate Change says sea levels are likely to rise one metre by the end of the century, possibly more, with melting Antarctic ice a major contributor.Simon Wallace showed us navigational charts drawn as recently as 2009 which were now out of date because of the ice retreat."We have literally gone off the charts," he said.Image:The William Glacier in Borgen Bay has retreated almost a mile in 20 years"As far as they were concerned, this was the land.
It's a very novel concept to a sailor because it looks like we are steaming up the beach."He said scientists on board the ship repeated the same measurements year after year showing a clear trend in climate change."We know it's a problem and it's getting worse.
Deal with it now in a well-ordered fashion before it is too late."
A World
| Unlimited Portal Access + Monthly Magazine - 12 issues-Publication from Jan 2021 |
Buy Our Merchandise (Peace Series)
SCAN and Contribute
- Details
- Category: A World
51