Tag Archive: Antarctica


Earth Watch Report   –  Biological Hazards

File:Two species of penguim at Arctowski Polish Station.jpg

Close to Arctowisky Station there is a huge penguin colony.  by  José Nestor Cardoso

Wikimedia . org

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Today Biological Hazard Antarctica [The area was not defined] Damage level Details

 

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RSOE EDIS

Biological Hazard in Antarctica on Tuesday, 06 May, 2014 at 10:11 (10:11 AM) UTC.

Description
A new kind of bird flu has been detected for the first time in Antarctica. The virus has been found in Adelie penguins – although it doesn’t appear to make them sick. Researchers say the virus is unlike any other avian flu known to science and raises a lot of unanswered questions. The findings show avian influenza viruses can get down to Antarctica and be maintained in penguin populations.
Biohazard name: H5Nx – Highly pathogenic avian influenza virus (new strain)
Biohazard level: 4/4 Hazardous
Biohazard desc.: Viruses and bacteria that cause severe to fatal disease in humans, and for which vaccines or other treatments are not available, such as Bolivian and Argentine hemorrhagic fevers, H5N1(bird flu), Dengue hemorrhagic fever, Marburg virus, Ebola virus, hantaviruses, Lassa fever, Crimean-Congo hemorrhagic fever, and other hemorrhagic or unidentified diseases. When dealing with biological hazards at this level the use of a Hazmat suit and a self-contained oxygen supply is mandatory. The entrance and exit of a Level Four biolab will contain multiple showers, a vacuum room, an ultraviolet light room, autonomous detection system, and other safety precautions designed to destroy all traces of the biohazard. Multiple airlocks are employed and are electronically secured to prevent both doors opening at the same time. All air and water service going to and coming from a Biosafety Level 4 (P4) lab will undergo similar decontamination procedures to eliminate the possibility of an accidental release.
Symptoms:
Status: confirmed

 

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Distinct Avian Influenza Virus Identified in Antarctica Penguins

First Posted: May 06, 2014 09:06 AM EDT

Distinct Avian Influenza Virus Identified in Antarctica Penguins

Distinct Avian Influenza Virus Identified in Antarctica Penguins (Photo : Aeron Hurt, WHO Collaborating Centre for Reference and Research on Influenza in Melbourne, Australia.)

An international team of researchers has identified a distinct avian influenza virus in a group of Antarctica’s Adelie penguins.

According to the finding documented in the journal of American Society of Microbiology, the avian influenza virus is different from the circulating avian flu.

Studies conducted earlier did not detect the live influenza virus in Antarctic’s penguins or other birds.

The study was led by associate professor Aeron Hurt, PhD, a senior research scientist at the WHO Collaborating Centre for Reference and Research on Influenza in Melbourne, Australia.

The researchers worked on the swab samples taken from Adelie penguins’ windpipes. They also collected samples from posterior openings. Apart from this, blood samples from 270 penguins were taken from two sites on the Antarctic Peninsula.

The two regions included Admiralty Bay and Rada Covadonga. All the samples were collected during January and February 2013.

 

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Antarctic rescue: all 52 ship passengers airlifted to safety

 

antarctic rescue
The helicopter from Chinese icebreaker Xue Long arrives to collect passengers. Photograph: Reuters

All 52 passengers, including tourists, scientists and journalists, on board a ship trapped in Antarctica have been rescued, the Australian Maritime Safety Authority (Amsa) has confirmed.

The Akademik Shokalskiy became stuck in the ice on Christmas Eve and two icebreakers, the Aurora Australis and Chinese vessel Xue Long, have been trying in vain to reach it.

On Thursday afternoon a helicopter sent from the Xue Long landed next to the ship and began evacuating passengers, dropping them on sea ice next to the Aurora Australis 14 nautical miles away. Five flights were made, carrying all non-crew and their luggage.

“Aurora Australis advised Amsa that helicopter operations had been completed at about 10.45pm AEDT and all passengers, luggage and equipment had been transferred,” Amsa said in a statement.

The acting director of the Australian Antarctic division of the department of environment, Jason Mundy, said the rescue was carried out without a hitch and it was a relief to have all passengers on board the Aurora Australis.

“The passengers seem very glad to now be with us and they are settling into their new accommodation. There are sufficient berths on the ship for the extra passengers and preparations have been made to ensure we can look after them well for this final part of their journey,” he said.

The “quite difficult” rescue was complicated by changing weather and ice conditions and passengers not trained for the complex situation, but it was not the most remote ever conducted by Amsa, said John Young, general manager of the authority’s rescue division.

“But we wouldn’t want it to be much more remote than this on a regular basis,” he said.

“Antarctica presents particular challenges, and we’re also grateful to the international Antarctic programs that co-operate in many respects, including this one.”

 

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Earth Watch Report  –  Volcanic Activity

File:Marie Byrd Land, West Antarctica by NASA.jpg

Image Source   :  Wikimedia Commons

Marie Byrd Land, West Antarctica

Author NASA/Michael Studinger

 

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Volcano Activity Antarctica Marie Byrd Land, [Mount Sidley Volcano] Damage level Details

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Volcano Activity in Antarctica on Wednesday, 11 December, 2013 at 04:25 (04:25 AM) UTC.

Description
A big, hot blob hiding beneath the bottom of the world could be evidence of a long-sought mantle plume under West Antarctica, researchers say. The possible hotspot �” a plume of superheated rock rising from Earth’s mantle �” sits under Marie Byrd Land, a broad dome at West Antarctica’s edge where many active volcanoes above and below the ice spit lava and ash. The hot zone was discovered with seismic imaging techniques that rely on earthquake waves to build pictures of Earth’s inner layers, similar to how a CT scan works. Beneath Marie Byrd Land, earthquake waves slow down, suggesting the mantle here is warmer than surrounding rocks. The strongest low-velocity zone sits below Marie Byrd Land’s Executive Committee Range, directly under the Mount Sidley volcano, said Andrew Lloyd, a graduate student at Washington University in St. Louis. “The slow velocities suggest that it’s a mantle hotspot,” Lloyd said on Monday during the fall meeting of the American Geophysical Union. The hot zone also matches up with Marie Byrd Land’s high topography and active volcanoes, Lloyd said. Many researchers have long suspected that Marie Byrd Land sits atop a hotspot, because the region swells above the surrounding topography like the top of a warm soufflé (and it has lots of volcanoes). But with few seismometers sitting on the ice, scientists were left speculating about what lies beneath Antarctica’s ice.

The evidence for the new hot zone, called a thermal anomaly, comes from a massive, temporary earthquake-monitoring network called Polenet that was installed between 2010 and 2012, giving scientists an unprecedented look at Antarctica’s crust and mantle. (A gravity survey conducted at the same time also suggests there is a big warm spot beneath this part of West Antarctica.) But confirming that Marie Byrd Land is truly above a hotspot may require a return trip to Antarctica for another seismic experiment, said Doug Wiens, principal investigator on Polenet. “What’s absolutely sure is there’s a big thermal anomaly, a big blob,” said Wiens, a seismologist at Washington University. “What’s less sure is whether that anomaly goes deeper.” The thermal anomaly extends 125 miles (200 kilometers) below Marie Byrd Land, Lloyd said. Below about 255 miles (410 km), where a mantle plume’s trailing tail would also leave a hotter-than-average mark in mantle rocks, there’s little evidence for a rising hotspot, said Erica Emry, a postdoctoral researcher at Pennsylvania State University. “There’s no smoking gun,” Emry said. However, more work remains to be done on the Polenet data, which could reveal new clues and further refine what the mantle looks like under West Antarctica, Emry told LiveScience’s OurAmazingPlanet.

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Active Volcano Discovered Under Ice Sheet in West Antarctica

Nov 18, 2013 by Sci-News.com

 

 

 

This map shows the location (red circle) of the newly discovered volcano in Marie Byrd Land, Antarctica.

This map shows the location (red circle) of the newly discovered volcano in Marie Byrd Land, Antarctica.

 

In 2010, the seismologists had set up two crossing lines of seismographs across Marie Byrd Land in West Antarctica. It was the first time scientists had deployed many instruments in the interior of the continent that could operate year-round even in the coldest parts of Antarctica.

 

The goal was essentially to weigh the ice sheet to help reconstruct Antarctica’s climate history. But to do this accurately the scientists had to know how the Earth’s mantle would respond to an ice burden, and that depended on whether it was hot and fluid or cool and viscous.

 

In the meantime, automated-event-detection software was put to work to comb the data for anything unusual.

 

In January 2010 and March 2011, the seismic network recorded two unusual bursts of seismic activity beneath Antarctica’s ice sheet.

 

“I started seeing events that kept occurring at the same location, which was odd. Then I realized they were close to some mountains, but not right on top of them,” explained PhD student Amanda Lough from Washington University in St. Louis, who is the lead author of the paper appearing in the journal Nature Geoscience.

 

“My first thought was, ‘OK, maybe it’s just coincidence.’ But then I looked more closely and realized that the mountains were actually volcanoes and there was an age progression to the range. The volcanoes closest to the seismic events were the youngest ones.”

 

The seismic events were weak and very low frequency, which strongly suggested they weren’t tectonic in origin.

 

While low-magnitude seismic events of tectonic origin typically have frequencies of 10 to 20 cycles per second, this shaking was dominated by frequencies of 2 to 4 cycles per second.

 

Ms Lough with colleagues used a global computer model of seismic velocities to relocate the hypocenters of the events to account for the known seismic velocities along different paths through the Earth. This procedure collapsed the swarm clusters to a third their original size. It also showed that almost all of the events had occurred at depths of 25 to 40 km.

 

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Antarctica, a land of ice and FIRE: Active volcano is discovered under continent  – and it could speed up melting

 

  • The volcano is buried 1km beneath the ice sheets of West Antarctica
  • Swarms of tremors were detected in January 2010 and February 2011
  • It was found near the extinct volcanoes of the Executive Committee Range
  • Ash found trapped in the ice came from an eruption 8,000 years ago
  • The volcano could cause the ice sheet to melt faster than first thought

By Victoria Woollaston

 

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Forget global warming, the ice sheets of Antarctica face a different and a potentially more imminent threat in the form an active volcano buried deep beneath. 

Researchers from Washington University discovered the volcano – which is yet to be named – by accident in the Marie Byrd Land region of West Antarctica. 

Swarms of tremors were detected in January 2010 and February 2011 and ash found trapped in the ice suggest it has been active for around 8,000 years.

The new volcano was found buried around a kilometre beneath an ice sheet in West Antarctica, close to the Executive Committee Range of mountains, pictured.

The new volcano was found buried beneath an ice sheet in West Antarctica, close to the Executive Committee Range of mountains, pictured. While trying to establish the weight of the ice sheet in the region, seismometers measured two swarms of tremors suggesting the volcano is active

MOUNTAINS DEEP BENEATH THE ICE

The as yet unnamed volcano buried beneath the ice sheet in Marie Byrd Land, West Antarctica is believed to be located close to the Executive Committee Range of extinct volcanoes.

The Range is made up consisting of five major volcanoes which were found by the United States Antarctic Service expedition in 1940.

It is named after the Antarctic Service Executive Committee.

The mountains are called Mount Sidley, Mount Waesche, Mount Hampton, Mount Cumming and Mount Hartington and are named after members of the committee.

Further mountains, thought to be extinct volcanoes, were discovered in East Antarctica in 1958.

This range is called the Gamburtsev Mountain Range and is covered by around 6 kilometres of snow and ice.

It is thought to be similar in size to the Alps.

Like with the new volcano, and the Executive Committee range, it is unclear exactly what caused these mountains to form.

 

Scientists now believe that a large eruption could cause the ice sheet to melt faster than first thought and cause sea levels to rise.

In January 2010, a team of scientists from the St. Louis-based university set up two crossing lines of seismographs across Marie Byrd Land in West Antarctica.

Doug Wiens, professor of earth and planetary science at Washington University, and his team wanted to weigh the ice sheet to help create a picture of Antarctica’s climate history.

Like a giant CT machine, the seismograph array used disturbances created by distant earthquakes to make images of the ice and rock deep within the region.

The technology found two bursts of seismic events between January 2010 and March 2011, which Wiens’ PhD student Amanda Lough believed were caused by a previously unseen volcano buried over half a mile (1 kilometre) beneath the ice sheet.  

‘I started seeing events that kept occurring at the same location, which was odd,’ Lough said.

‘Then I realised they were close to some mountains – but not right on top of them.

‘My first thought was, “Okay, maybe it’s just coincidence.” But then I looked more closely and realised that the mountains were actually volcanoes and there was an age progression to the range.

‘The volcanoes closest to the seismic events were the youngest ones.’

The tremors were weak and very low frequency, which Lough said suggested they weren’t caused by movements in tectonic plates, associated with earthquakes. 

The tremors beneath Marie Byrd Land, pictured, were weak and very low frequency, which Lough said suggested they weren't caused by movements in tectonic plates

The tremors beneath Marie Byrd Land, pictured, were low frequency suggesting they weren’t caused tectonic plates moving. Low-magnitude tectonic tremors typically have frequencies of 10 to 20 cycles per second. The shaking discovered by Lough was 2 to 4 cycles per second making it more like volcanic activity

For example, low-magnitude seismic tremors caused by tectonic movement typically have frequencies of 10 to 20 cycles per second, continued Lough.

The shaking she discovered was in frequencies of 2 to 4 cycles per second.

Lough then used a global computer model of seismic speeds to find exactly where the seismic events were taking place. 

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Commission for the Conservation of Antarctic Marine Living Resources negotiations aim to ban fishing across much of Southern Ocean

Graphic: proposed areas of protection in Antarctica

Emperor Penguin in Australian Antarctic Territory

Emperor Penguin in Australian Antarctic Territory. Photograph: Pete Oxford/Corbis

Fishing and oil drilling could be banned across more than two million square kilometres of the frigid seas around Antarctica in a historic attempt to conserve the last pristine ocean.

Negotiations this week at a meeting of the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) will centre on a proposal for a 1.25m square kilometre “no take” zone, which would cover much of the Ross Sea. Another proposal would establish several other smaller protected areas in the seas around East Antarctica, adding a further 1.9m sq km protection zone. A third reserve, proposed by Germany and backed by Britain, would bar fishing from a large portion of the Weddell Sea, which is the site of the British Antarctic Survey’s research station, and where Ernest Shackleton’s ship Endurance was crushed by ice in 1915.

The prize, says a coalition of 30 conservation groups including Greenpeace and WWF, is the long-term protection of the nutrient-rich seas around the continent, which are home to more than 10,000 unique species – including most of the world’s penguins, whales, seabirds, squid and Antarctic toothfish. The seas are also full of krill, the minute shrimp-like creatures that eat algae and plankton and are the main food for whales, penguins, seals, albatrosses and petrels, but are also increasingly used as feed for fish farms and health supplements.

According to some scientists, the two proposed marine protection areas are vitally important because they support a high percentage of all marine life. At the moment just 1% of the world’s oceans is protected, with the result that most of the world’s fishing grounds have been significantly depleted.

 

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OZONE NEWS


by Staff Writers
Bindura, Zimbabwe (UPI) Oct 14, 2013

 


disclaimer: image is for illustration purposes only

 

A decades-long warming trend in southern Africa is likely the result of the ozone hole over the Antarctic and its effect on wind circulation, researchers say.

In early summer southern Africa is affected by what is known as the Angola Low, a low-pressure system that pulls in warm air from the lower latitudes, increasing temperatures.

But during the past 20 years, the researchers said, the annual rise in temperatures has been nearly two degrees Fahrenheit hotter than normal.

Desmond Manatsa, a climate scientist at Bindura University of Science in Zimbabwe, working with international colleagues, analyzed climate data from 1979 to 2010, and found as the size of the ozone hole — caused by human use of fluorocarbons — grew, temperatures in southern Africa rose as well.

 

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EcoAlert: Changes in Earth’s Orbit Appear to be Key to Antarctic Warming

Antarctica-warming-660
Image Credit:  Adventure Journal

Analysis of an ice core taken by the National Science Foundation- (NSF) funded West Antarctic Ice Sheet (WAIS) Divide drilling project reveals that warming in Antarctica began about 22,000 years ago, a few thousand years earlier than suggested by previous records. This timing shows that West Antarctica did not “wait for a cue” from the Northern Hemisphere to start warming, as scientists had previously supposed.

For more than a century scientists have known that Earth’s ice ages are caused by the wobbling of the planet’s orbit, which changes its orientation to the sun and affects the amount of sunlight reaching higher latitudes.

The Northern Hemisphere’s last ice age ended about 20,000 years ago, and most evidence had indicated that the ice age in the Southern Hemisphere ended about 2,000 years later, suggesting that the South was responding to warming in the North.
But research published online Aug. 14 in the journal Nature shows that Antarctic warming began at least two, and perhaps four, millennia earlier than previously thought.

Most previous evidence for Antarctic climate change had come from ice cores drilled in East Antarctica, the highest and coldest part of the continent. However, a U.S.-led research team studying the West Antarctic core found that warming there was well underway 20,000 years ago.

WAIS Divide is a large-scale and multi-year glaciology project supported by the U.S. Antarctic Program (USAP), which NSF manages. Through USAP, NSF coordinates all U.S. science on the southernmost continent and aboard vessels in the Southern Ocean and provides the necessary logistics to make the science possible.

 

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File:Iceberg with hole crop.jpg

Image Source  :  Wikimedia Commons

Author Brocken Inaglory

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Live Science

Seaweed could smother polar underwater ecosystems as melting sea ice exposes the seafloor to more sunlight, new research shows.

Animals that dwell on the seafloor of the Arctic and Antarctic spend most of their lives in total darkness: Sea ice blocks rays during the spring and early summer, and the sun sets completely in the winter. Late summer and early fall — when the ocean warms up enough to thaw the ice — often marks the only time these critters see light.

But as climate change causes sea ice to begin melting earlier and earlier in the summer, shallow-water ecosystems will soak up increasingly more rays. New research from a team of Australian biologists suggests this could cause a major shift in the seafloor communities along the coast of Antarctica, where invertebrates like sponges, worms and tunicates — globular organisms that anchor to rocks on the seafloor — currently dominate. A manuscript of the report is currently in press at the journal Global Change Biology. [6 Unexpected Effects of Climate Change]

“Some areas where ice breaks out early in summer are already shifting to algal domination,” said Graeme Clark, a biologist at the University of New South Wales who was involved in the study.

Seasons and tipping points

Early-summer ice melt not only lengthens the amount of time photosynthesizing organisms like macroalgae (or seaweed) can thrive under the sun during the summer, but it also increases the intensity of that exposure. The sun sits highest in the sky during the summer solstice — the period when Earth tilts most directly toward the sun — that occurs between June 20 and 23 in the Northern Hemisphere and Dec. 20 and 23 in the Southern Hemisphere, depending on the phase of the Earth’s orbit. Rays travel directly to the seafloor during this time. During spring and fall, however, low-angle rays reflect off the sea surface and often never make it to the seafloor.

This compounding effect of a longer sunlit season and higher-intensity rays could exponentially increase the amount of sunlight hitting benthic, or seafloor, communities in the coming decades and cause major tipping points for those invertebrate-dominated ecosystems, Clark said.

Tipping points occur when relatively minor environmental changes — like sea ice melting several days earlier than usual — cause rapid and significant ecological transformation. In this case, the tipping point would push ecosystems from invertebrate-dominated to algae-dominated.

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Russia blocks creation of two huge Marine Protected Areas in Antarctica

An extraordinary meeting of the Commission of Antarctic Marine Living Resources (CCAMLR) to establish Marine Protected Areas (MPA) in the Ross Sea region and in East Antarctica wrapped up on Tuesday without an agreement after Russia with support from Ukraine blocked the initiative.

The MPAs initiative will be again discussed at the CCAMLR regular meeting in Hobart, Australia

The MPAs initiative will be again discussed at the CCAMLR regular meeting in Hobart, Australia

The nyet squad

The nyet squad

“The outcome is not what we expected or hoped for … We did not reach a consensus,” Terje Lobach, the Commission’s chairperson, said on Tuesday at the end of the meeting in the northern German town of Bremerhaven.

Delegates at the conference in Bremerhaven looked at two proposals to create huge ocean sanctuaries off Antarctica.

The first, which was proposed by the United States and New Zealand, would have covered an area of 1.6 million square kilometers (640,000 square miles) of the Ross Sea, a deep bay on the Pacific side of the continent.

The other, supported by the European Union, France, and Australia, would have protected 1.9 million square kilometers on the Indian Ocean side of Antarctica.

However, the Russian delegation supported by neighboring Ukraine, raised questions about the CCAMLR legal power to implement any such proposal, according to environmental groups.

“The actions of the Russian delegation have put international cooperation and goodwill at risk, the two key ingredients needed for global marine conservation”, said Andrea Kavanagh, in charge of the Southern Ocean Sanctuaries campaign at the US green group Pew Environment.

 

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Earth Watch Report  –  Climate Change

 

 

 

 

 

See Additional  Photos Here

 

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10.07.2013 Climate Change Antarctica [Pine Island Glacier] Damage level
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Climate Change in Antarctica on Wednesday, 10 July, 2013 at 10:15 (10:15 AM) UTC.

 

Description
Pine Island Glacier (PIG), the longest and fastest flowing glacier in the Antarctic, has spawned a huge iceberg. The block measures about 720 sq km in area – roughly eight times the size of Manhattan Island in New York. Scientists have been waiting for the PIG to calve since October 2011 when they first noticed a spectacular crack spreading across its surface. Confirmation that the fissure had extended the full width of the glacier was obtained on Monday. It was seen by the German TerraSAR-X satellite. This carries a radar instrument that can detect the surface of the ice stream even though the Antarctic is currently in the grip of winter darkness. The berg that broke away was part of the PIG’s ice shelf – the front segment of the glacier that lifts up and floats as it pushes out into the ocean. The shelf will reach tens of km beyond the grounding line. German researchers have been receiving images from TerraSAR-X every three days or so, hoping to understand better the processes that drive the glacier forward and prompt it to fracture. This will help them improve the computer models that are used to forecast future changes in the Antarctic. “We were very keen to see how the crack propagated,” said Prof Angelika Humbert, a glaciologist with the Alfred Wegener Institute. “We need proper calving laws, to be able to describe the evolution of ice sheets over centuries,” she told BBC News.

Very big tabular bergs will come off the end of the ice shelf every 6-10 years. Previous notable events occurred in 2007 and 2001. It is a very natural process and scientists say it should not be tied directly to the very real climate changes that are also affecting this part of the West Antarctic Ice Sheet. Satellite and airborne measurements have recorded a marked thinning and a surge in velocity of the PIG in recent decades. This has been attributed in part to warmer waters getting under, and melting, the ice shelf. The PIG’s grounding line has pulled back further and further towards the land. The glacier’s behaviour means it is now under close scrutiny, not least because it drains something like 10% of all the ice flowing off the west of the continent. “The PIG is the most rapidly shrinking glacier on the planet,” explained Prof David Vaughan from the British Antarctic Survey (BAS). “It’s losing more ice than any other glacier on the planet, and it’s contributing to sea level rise faster than any other glacier on the planet. That makes it worthy of study.” BAS has recently deployed a series of instrumented “javelins” along the PIG to monitor its movement. When the big crack propagating across the 30km width of the PIG was first photographed in 2011 by a Nasa airborne expedition, many assumed the moment of final calving would come quite quickly.

That it took almost two years for the tabular berg to break away is something of a surprise, concedes Prof Humbert. What should not be a surprise, she says, is that it has occurred in deep winter when the ocean is covered in sea-ice. This relatively thin covering would always be overwhelmed by the internal stresses in the massive ice shelf. What will be interesting now, she adds, is to see how long it takes for the berg to move out of the bay in front of it. It could take several months. TerraSAR-X will provide the tell-tale data. The world’s largest recorded iceberg was the tabular block that became known as B-15. When it broke off the Ross Ice Shelf in 2001, it had a surface area of about 11,000 sq km. It took years to melt away as it moved out into the Southern Ocean.

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A glacier

Pine Island Glacier’s vast crack, pictured via NASA satellite late last fall.

Image courtesy NASA/METI/ERSDAC/JAROS

 

Richard A. Lovett

 

for National Geographic News

 

Published February 2, 2012

 

With a gargantuan crack slowly splitting it apart, Antarctica‘s fastest-melting glacier is about to lose a chunk of ice larger than all of New York City, scientists say.

(Also see “Manhattan-Size Ice Island Cracks in Half.”)

The crevasse stretches 19 miles (30 kilometers) long and up to 260 feet (80 meters) wide, as shown in a picture taken by NASA’s Terra satellite in October and featured this week as a NASA Image of the Day.

Snaking across the floating tongue of the Pine Island Glacier in West Antarctica, the crack is expected to create an iceberg 350 square miles (907 square kilometers)—versus 303 square miles (785 square kilometers) for Manhattan, Brooklyn, Queens, Staten Island, and the Bronx combined, according to NASA.

As for when the iceberg might shove off, “that is very difficult to predict,” said oceanographer Eric Rignot of NASA’s Jet Propulsion Laboratory, “but in the coming months for sure.”

Glacier “Contributing Most to Sea Level”

Usually there’s nothing extraordinary about a glacier calving, said glaciologist Ted Scambos of the National Snow and Ice Data Center (NSIDC) in Boulder, Colorado.

Glaciers that flow into the sea, like the Pine Island Glacier, go through a normal cycle in which the floating section grows, stresses mount, and an iceberg breaks off, Scambos said.

“That is nothing unusual in most cases.”

 

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