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Strong winds are causing Totten glacier to melt

New study found that East Antarctica’s largest glacier is melting from beneath This happens as stron..

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  • New study found that East Antarctica’s largest glacier is melting from beneath
  • This happens as strong winds over Southern Ocean allow warm water to rise
  • Winds are expected to intensify with climate change, causing further melting

By Cheyenne Macdonald For Dailymail.com

Published: 12:18 EDT, 3 November 2017 | Updated: 12:18 EDT, 3 November 2017

With the potential to cause sea levels to rise by more than 11 feet and unleash the ice of the East Antarctic Ice Sheet, the massive Totten Glacier has come to be known as the ‘sleeping giant.’

And now, scientists have discovered that strong winds over the Southern Ocean could be causing it to wake up.

A new study has found that East Antarctica’s largest glacier is melting from beneath, as winds transport warm water to the ice – and, these winds are expected to intensify with climate change, the experts warn.

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The research revealed that the glacier’s flow speeds up when winds over the Southern Ocean are strong. These winds pull warm water up from the deep ocean, in a process known as upwelling

The research revealed that the glacier’s flow speeds up when winds over the Southern Ocean are strong. These winds pull warm water up from the deep ocean, in a process known as upwelling

EAST ANTARCTICA MORE STABLE THAN THE WEST

A recent study conducted by researchers based at Indiana University-Purdue University Indianapolis has found that the central core of the East Antarctic ice sheet should remain stable even if the West Antarctic ice sheet melts.

The West Antarctic ice sheet is a marine-based ice sheet that is mostly grounded below sea level, which makes it much more susceptible to changes in sea level and variations in ocean temperature than the East Antarctic Ice Sheet.

By contrast the East Antarctic ice sheet has been considered relatively stable because most of the ice sheet was though to rest on bedrock above sea level, making it less susceptible to changes in climate.

In the study, led by researchers at the University of Texas at Austin, used satellite images and wind stress data to investigate the effect of wind on the water beneath the glacier.

While the glacier is known to speed up some years, it also slows down in others.

The research revealed that the glacier’s flow speeds up when winds over the Southern Ocean are strong.

These winds pull warm water up from the deep ocean, in a process known as upwelling.

The warm water climbs to the continental shelf – and, once it reaches the coast, it circulates beneath a floating chunk of the glacier, and causes the ice sheet to melt from below, according to the researchers.

‘Totten has been called the sleeping giant because it’s huge and has been seen as insensitive to changes in its environment,’ said lead author Chad Greene, a PhD candidate at the University of Texas Institute for Geophysics (UTIG).

‘But we’ve shown that if Totten is asleep, it’s certainly not in a coma – we’re seeing signs of responsiveness, and it might just take the wind blowing to wake it up.’

Wind strength varies from year to year, the researchers explain.

But, climate change is expected to intensify the winds over the Southern Ocean, which could, in turn, effect the melting of the Totten Glacier.

The process does not require the air or ocean temperatures to rise – instead, upwelling occurs as the wind displaces the surface water, making way for the deeper, warmer water.

‘It’s like when you blow across a hot bowl of soup and little bits of noodles from the bottom begin to swirl around and rise to the top,’ said Greene.

The new study follows up on previous research led by a team with the Australian Antarctic Division at the Antarctic Climate & Ecosystems Cooperative Research Center.

That research found that the warm water below Totten causes the glacier to detach from the seafloor, and instead float.

This can cause the flow to further accelerate.

With the potential to cause sea levels to rise by more than 11 feet and unleash the ice of the East Antarctic Ice Sheet, the massive Totten Glacier has come to be known as the ‘sleeping giant’With the potential to cause sea levels to rise by more than 11 feet and unleash the ice of the East Antarctic Ice Sheet, the massive Totten Glacier has come to be known as the ‘sleeping giant’

With the potential to cause sea levels to rise by more than 11 feet and unleash the ice of the East Antarctic Ice Sheet, the massive Totten Glacier has come to be known as the ‘sleeping giant’

‘The remaining question was, why do the canyons beneath Totten get flushed with warm water some years and cold water other years,’ said Jason Roberts, a glaciologist who led the earlier study.

The findings suggest melting at Totten could become more extreme as winds grow stronger with climate change.

‘Ice sheet sensitivity to wind forcing has been hypothesized for a long time, but it takes decades of observation to show unequivocal cause and effect,’ said Donald Blankenship, a senior researcher at UTIG who contributed to this study and Roberts’ study.

‘Now we’re at the point where we can explicitly show the links between what happens in the atmosphere, what happens in the ocean, and what happens to the Antarctic Ice Sheet.’

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Australia

Sydney seaplane crash: Exhaust fumes affected pilot, report confirms

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The pilot of a seaplane that crashed into an Australian river, killing all on board, had been left confused and disorientated by leaking exhaust fumes, investigators have confirmed.

The Canadian pilot and five members of a British family died in the crash north of Sydney in December 2017.

All were found to have higher than normal levels of carbon monoxide in their blood, a final report has found.

It recommended the mandatory fitting of gas detectors in all such planes.

British businessman Richard Cousins, 58, died alongside his 48-year-old fiancée, magazine editor Emma Bowden, her 11-year-old daughter Heather and his sons, Edward, 23, and William, 25, and pilot Gareth Morgan, 44. Mr Cousins was the chief executive of catering giant Compass.

The family had been on a sightseeing flight in the de Havilland DHC-2 Beaver plane when it nose-dived into the Hawkesbury River at Jerusalem Bay, about 50km (30 miles) from the city centre.

The final report by the Australian Transport Safety Bureau (ATSB) confirmed the findings of an interim report published in 2020.

It said pre-existing cracks in the exhaust collector ring were believed to have released exhaust gas into the engine bay. Holes left by missing bolts in a firewall then allowed the fumes to enter the cabin.

“As a result, the pilot would have almost certainly experienced effects such as confusion, visual disturbance and disorientation,” the report said.

“Consequently, it was likely that this significantly degraded the pilot’s ability to safely operate the aircraft.”

The ATSB recommended the Civil Aviation Safety Authority consider mandating the fitting of carbon monoxide detectors in piston-engine aircraft that carry passengers.

It previously issued safety advisory notices to owners and operators of such aircraft that they install detectors “with an active warning” to pilots”. Operators and maintainers of planes were also advised to carry out detailed inspections of exhaust systems and firewalls.

Read from source: https://www.bbc.com/news/world-australia-55862128

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Australia

Australia unlikely to fully reopen border in 2021, says top official

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Australia is unlikely to fully open its borders in 2021 even if most of its population gets vaccinated this year as planned, says a senior health official.

The comments dampen hopes raised by airlines that travel to and from the country could resume as early as July.

Department of Health Secretary Brendan Murphy made the prediction after being asked about the coronavirus’ escalation in other nations.

Dr Murphy spearheaded Australia’s early action to close its borders last March.

“I think that we’ll go most of this year with still substantial border restrictions,” he told the Australian Broadcasting Corporation on Monday.

“Even if we have a lot of the population vaccinated, we don’t know whether that will prevent transmission of the virus,” he said, adding that he believed quarantine requirements for travellers would continue “for some time”.

Citizens, permanent residents and those with exemptions are allowed to enter Australia if they complete a 14-day hotel quarantine at their own expense.

Qantas – Australia’s national carrier – reopened bookings earlier this month, after saying it expected international travel to “begin to restart from July 2021.”

However, it added this depended on the Australian government’s deciding to reopen borders.

Australia’s tight restrictions

The country opened a travel bubble with neighbouring New Zealand late last year, but currently it only operates one-way with inbound flights to Australia.

Australia has also discussed the option of travel bubbles with other low-risk places such as Taiwan, Japan and Singapore.

A vaccination scheme is due to begin in Australia in late February. Local authorities have resisted calls to speed up the process, giving more time for regulatory approvals.

Australia has so far reported 909 deaths and about 22,000 cases, far fewer than many nations. It reported zero locally transmitted infections on Monday.

Experts have attributed much of Australia’s success to its swift border lockdown – which affected travellers from China as early as February – and a hotel quarantine system for people entering the country.

Local outbreaks have been caused by hotel quarantine breaches, including a second wave in Melbourne. The city’s residents endured a stringent four-month lockdown last year to successfully suppress the virus.

Other outbreaks – including one in Sydney which has infected about 200 people – prompted internal border closures between states, and other restrictions around Christmas time.

The state of Victoria said on Monday it would again allow entry to Sydney residents outside of designated “hotspots”, following a decline in cases.

While the measures have been praised, many have also criticised them for separating families across state borders and damaging businesses.

Dr Murphy said overall Australia’s virus response had been “pretty good” but he believed the nation could have introduced face masks earlier and improved its protections in aged care homes.

In recent days, Australia has granted entry to about 1,200 tennis players, staff and officials for the Australian Open. The contingent – which has recorded at least nine infections – is under quarantine.

Read from source: https://www.bbc.com/news/world-australia-55699581

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Australia

Covid: Brisbane to enter three-day lockdown over single infection

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The Australian city of Brisbane has begun a snap three-day lockdown after a cleaner in its hotel quarantine system became infected with coronavirus.

Health officials said the cleaner had the highly transmissible UK variant and they were afraid it could spread.

Brisbane has seen very few cases of the virus beyond quarantined travellers since Australia’s first wave last year.

It is the first known instance of this variant entering the Australian community outside of hotel quarantine.

The lockdown is for five populous council areas in Queensland’s state capital.

Premier Annastacia Palaszczuk announced the measure on Friday morning local time, about 16 hours after the woman tested positive.

Ms Palaszczuk said the lockdown aimed to halt the virus as rapidly as possible, adding: “Doing three days now could avoid doing 30 days in the future.”

“I think everybody in Queensland… knows what we are seeing in the UK and other places around the world is high rates of infection from this particular strain,” she said.

“And we do not want to see that happening here in our great state.”

Australia has reported 28,500 coronavirus infections and 909 deaths since the pandemic began. By contrast, the US, which is the hardest-hit country, has recorded more than 21 million infections while nearly 362,000 people have died of the disease.The lockdown will begin at 18:00 on Friday (08:00 GMT) in the Brisbane city, Logan and the Ipswich, Moreton and Redlands local government areas.

Residents will only be allowed to leave home for certain reasons, such as buying essential items and seeking medical care.

For the first time, residents in those areas will also be required to wear masks outside of their homes.

Australia has faced sporadic outbreaks over the past year, with the most severe one in Melbourne triggering a lockdown for almost four months.

A pre-Christmas outbreak in Sydney caused fresh alarm, but aggressive testing and contact-tracing has kept infection numbers low. The city recorded four local cases on Friday.

Prime Minister Scott Morrison’s government has pledged to start mass vaccinations in February instead of March as was planned.

Lockdown interrupts ‘near normal’ life in Brisbane

Simon Atkinson, BBC News in Brisbane

At 8:00 today I popped to the local supermarket for some bread, milk – and because it’s summer here – a mango. I was pretty much the only customer.

When I went past the same shop a couple of hours later it was a different story – 50 people standing in the drizzle – queuing to get inside as others emerged with bulging shopping bags. “Heaps busier than Christmas,” a cheery trolley attendant told me. “It’s off the scale”.

Despite the “don’t panic” messages from authorities, pictures on social media show it’s a pattern being repeated across the city.

While shutdowns are common around the world, the tough and sudden stay-at-home order for Brisbane has caught people on the hop here after months of near normality.

But while such a rapid, hard lockdown off the back of just a single case of Covid-19 will seem crazy in some parts of the world, I’ve not come across too many people complaining.

And I don’t think that’s just because Aussies love to follow a rule. This is the first time the UK variant of the virus has been detected in the community in Australia.

And nobody here wants Brisbane to go through what Melbourne suffered last year. Even if it means going without mangoes.

Read from source: https://www.bbc.com/news/world-australia-55582836

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