Latest news with #A81
Courier-Mail
5 days ago
- Science
- Courier-Mail
Tides could help predict when huge icebergs break loose: study
Don't miss out on the headlines from Breaking News. Followed categories will be added to My News. Ocean tides can trigger city-sized icebergs to break off from Antarctic ice shelves, scientists said on Thursday, offering a potential way to predict these dramatic events in the future. It is not normally possible to forecast when icebergs break free, or calve, although the timing is important because these behemoths change the shape of ice sheets and affect global sea levels. Yet when a chunk of ice the size of Greater London suddenly broke off the Brunt Ice Shelf in 2023 and started drifting away, glaciologist Oliver Marsh was not surprised. Marsh told AFP he had predicted that a huge iceberg breaking off was "imminent within the next weeks to months". The British Antarctic Survey researcher had spent years studying the huge crack that would create the 550-square-kilometre (210-square-mile) iceberg named A81. As Marsh had anticipated, the calving occurred at the peak of spring tide, when there is the biggest difference between the ocean's high and low tide. New research led by Marsh, published in the journal Nature Communications on Thursday, used modelling to show that the calving was triggered by the tide, along with high winds and stress on the ice. After A81 broke off, Marsh visited the ice shelf to see how open water had replaced what had previously been "ice as far as you could see". "It was sad to see it go, in a way," he said. A81 is currently drifting up the eastern side of the Antarctica Peninsula towards the Weddell Sea. It remains to be seen whether it will come close to South Georgia island, which is an important breeding ground for penguins, seals and other animals. - 'Out of balance' - The world's biggest iceberg, A23a, ran aground not too far from South Georgia earlier this year but is not thought to pose a threat to wildlife. Now that A23a is exposed to the waves of the Southern Ocean, its "days are numbered", Marsh said. He emphasised that iceberg calving is a natural process which balances out the massive amount of snow that falls on Antarctica every year. However, "now we're out of balance", Marsh added. Antarctica loses ice in two ways -- icebergs calving and ice sheets melting. And ice sheets are melting at a rapidly increasing rate as oceans warm due to human-driven climate change, scientists have warned. "We don't know whether calving rates have gone up" because they happen relatively infrequently, Marsh said. A81 was the second of three mammoth icebergs that have broken free of the Brunt Ice Shelf since 2021. "We are expecting a very large calving event at some point from this area" in the future, Marsh said. But he could not give a timeframe. "Whilst we're saying we are a step closer to being able to predict these events... it is still difficult to predict." dl/gil Originally published as Tides could help predict when huge icebergs break loose: study
Straits Times
5 days ago
- Science
- Straits Times
Tides could help predict when huge icebergs break loose: Study
Find out what's new on ST website and app. Iceberg calving is a natural process which balances out the massive amount of snow that falls on Antarctica every year. PARIS – Ocean tides can trigger city-sized icebergs to break off from Antarctic ice shelves, scientists said on July 24, offering a potential way to predict these dramatic events in the future. It is not normally possible to forecast when icebergs break free, or calve, although the timing is important because these behemoths change the shape of ice sheets and affect global sea levels. Yet when a chunk of ice the size of Greater London suddenly broke off the Brunt Ice Shelf in 2023 and started drifting away, glaciologist Oliver Marsh was not surprised. Dr Marsh told AFP he had predicted that a huge iceberg breaking off was 'imminent within the next weeks to months'. The British Antarctic Survey researcher had spent years studying the huge crack that would create the 550sq km iceberg named A81. As Dr Marsh had anticipated, the calving occurred at the peak of spring tide, when there is the biggest difference between the ocean's high and low tide. New research led by Dr Marsh, published in the journal Nature Communications on July 24, used modelling to show that the calving was triggered by the tide, along with high winds and stress on the ice. Top stories Swipe. Select. Stay informed. Asia Live: People evacuated from border regions amid deadly Thailand-Cambodia clash Asia 11 Thai civilians killed as Thai and Cambodian militaries clash at disputed border: Reports Asia Deadly Thai-Cambodian dispute puts Asean's relevance on the line Singapore Singapore says prolonged suffering of civilians in Gaza is 'unconscionable' Singapore Khatib Camp to make way for housing, with its functions moving to Amoy Quee Camp Singapore First BTO flats in Greater Southern Waterfront, Mount Pleasant to go on sale in October Singapore Mindef to set up new volunteer management unit to grow volunteer pool Singapore Primary 1 registration: 29 schools to conduct ballot in Phase 2B After A81 broke off, Dr Marsh visited the ice shelf to see how open water had replaced what had previously been 'ice as far as you could see'. 'It was sad to see it go, in a way,' he said. A81 is currently drifting up the eastern side of the Antarctica Peninsula towards the Weddell Sea. It remains to be seen whether it will come close to South Georgia island, which is an important breeding ground for penguins, seals and other animals. 'Out of balance' The world's biggest iceberg, A23a, ran aground not too far from South Georgia earlier in 2025 but is not thought to pose a threat to wildlife. Now that A23a is exposed to the waves of the Southern Ocean, its 'days are numbered', Dr Marsh said. He emphasised that iceberg calving is a natural process which balances out the massive amount of snow that falls on Antarctica every year. However, 'now we're out of balance', Dr Marsh added. Antarctica loses ice in two ways – icebergs calving and ice sheets melting. And ice sheets are melting at a rapidly increasing rate as oceans warm due to human-driven climate change, scientists have warned. 'We don't know whether calving rates have gone up' because they happen relatively infrequently, Dr Marsh said. A81 was the second of three mammoth icebergs that have broken free of the Brunt Ice Shelf since 2021. 'We are expecting a very large calving event at some point from this area' in the future, Dr Marsh said. But he could not give a timeframe. 'While we're saying we are a step closer to being able to predict these events... it is still difficult to predict.' AFP
The Sun
5 days ago
- Science
- The Sun
Tides may predict when massive Antarctic icebergs break off
PARIS: Ocean tides could help predict when enormous icebergs break away from Antarctic ice shelves, according to new research. The findings, published in Nature Communications, suggest that tidal forces, along with wind stress, play a key role in triggering these dramatic events. Glaciologist Oliver Marsh from the British Antarctic Survey had anticipated the 2023 calving of iceberg A81, which was the size of Greater London. His team's modelling confirmed that the break occurred during peak spring tide, when tidal differences are greatest. The study highlights how calving is a natural process that balances Antarctica's snowfall. However, rising ocean temperatures due to climate change are accelerating ice sheet melt, disrupting this equilibrium. 'We don't know whether calving rates have gone up,' Marsh said, noting the challenge in tracking these rare events. A81 is now drifting towards the Weddell Sea, while the world's largest iceberg, A23a, is slowly disintegrating in the Southern Ocean. Scientists remain uncertain whether A81 will threaten South Georgia, a critical habitat for penguins and seals. Marsh warns that another major calving event is expected from the Brunt Ice Shelf, though predicting exact timing remains difficult. 'Whilst we're a step closer to forecasting these events, it's still challenging,' he said. – AFP
Int'l Business Times
5 days ago
- Science
- Int'l Business Times
Tides Could Help Predict When Huge Icebergs Break Loose: Study
Ocean tides can trigger city-sized icebergs to break off from Antarctic ice shelves, scientists said on Thursday, offering a potential way to predict these dramatic events in the future. It is not normally possible to forecast when icebergs break free, or calve, although the timing is important because these behemoths change the shape of ice sheets and affect global sea levels. Yet when a chunk of ice the size of Greater London suddenly broke off the Brunt Ice Shelf in 2023 and started drifting away, glaciologist Oliver Marsh was not surprised. Marsh told AFP he had predicted that a huge iceberg breaking off was "imminent within the next weeks to months". The British Antarctic Survey researcher had spent years studying the huge crack that would create the 550-square-kilometre (210-square-mile) iceberg named A81. As Marsh had anticipated, the calving occurred at the peak of spring tide, when there is the biggest difference between the ocean's high and low tide. New research led by Marsh, published in the journal Nature Communications on Thursday, used modelling to show that the calving was triggered by the tide, along with high winds and stress on the ice. After A81 broke off, Marsh visited the ice shelf to see how open water had replaced what had previously been "ice as far as you could see". "It was sad to see it go, in a way," he said. A81 is currently drifting up the eastern side of the Antarctica Peninsula towards the Weddell Sea. It remains to be seen whether it will come close to South Georgia island, which is an important breeding ground for penguins, seals and other animals. The world's biggest iceberg, A23a, ran aground not too far from South Georgia earlier this year but is not thought to pose a threat to wildlife. Now that A23a is exposed to the waves of the Southern Ocean, its "days are numbered", Marsh said. He emphasised that iceberg calving is a natural process which balances out the massive amount of snow that falls on Antarctica every year. However, "now we're out of balance", Marsh added. Antarctica loses ice in two ways -- icebergs calving and ice sheets melting. And ice sheets are melting at a rapidly increasing rate as oceans warm due to human-driven climate change, scientists have warned. "We don't know whether calving rates have gone up" because they happen relatively infrequently, Marsh said. A81 was the second of three mammoth icebergs that have broken free of the Brunt Ice Shelf since 2021. "We are expecting a very large calving event at some point from this area" in the future, Marsh said. But he could not give a timeframe. "Whilst we're saying we are a step closer to being able to predict these events... it is still difficult to predict."
