A Trillion Tonnes of Antarctica Fell into the Sea

In late August 2016, sunlight returned to the Antarctic Peninsula and unveiled a rift across the Larsen C Ice Shelf that had grown longer and deeper over the austral winterNASA/John Sonntag

Antarctica, Earth’s coldest continent, is known for its remoteness, its unique fauna, and its frigid surface of ice. Around Antarctica’s periphery, dozens of ice shelves (that is, masses of glacier-fed floating ice that are attached to land) project outward into the Southern Ocean. The two largest ice shelves, the Ross Ice Shelfand the Ronne Ice Shelf, span a combined area of nearly 350,000 square km (about 135,000 square miles)—an area roughly equivalent to Venezuela—but Antarctica’s Larsen Ice Shelf, the continent’s fourth largest, has received the bulk of the attention over the last 25 years because it is slowly coming apart. The latest episode in this saga occurred between July 10 and July 12, 2017, when a one-trillion-metric-ton chunk of ice—possibly critical to holding back a large section of the remaining shelf—calved (that is, broke away).

The Larsen Ice Shelf is located on the eastern side of the Antarctic Peninsula and juts out into the Weddell Sea. It originally covered an area of 86,000 square km (33,000 square miles), but its footprint has declined dramatically, possibly as a result of warming air temperatures over the Antarctic Peninsula during the second half of the 20th century. In January 1995 the northern portion (known as Larsen A) disintegrated, and a giant iceberg calved from the middle section (Larsen B). Larsen B steadily retreated until February–March 2002, when it too collapsed and disintegrated. The southern portion (Larsen C) made up two-thirds of the ice shelf’s original extent, covering an area of about 50,000 square km (19,300 square miles) alone. Its thickness ranges from 200 to 600 meters (about 660 to 1,970 feet). Sometime between July 10 and July 12, 2017, a 5,800-square-km- (~2,240-square-mile-) section—some 12% of the Larsen C—broke away. Signs of Larsen C’s impending fracture date back to 2012, when satellite monitoring detected a steadily growing crack near the Joerg Peninsula at the southern end of the shelf. NASA and ESA satellites tracked the rift as it grew to more than 200 km (124 miles) in length and the huge iceberg separated from the continent.

Although some 88% of Larsen C remains, many scientists worry that it will fall apart like Larsen A and Larsen B, because the loss of such a huge area of the shelf’s ice front may make the remainder of the ice shelf less stable. The shelf’s mass, along with the fact that it is pinned behind shallow undersea outcrops of rock below, creates a natural dam that significantly slows the flow of the ice into the Weddell Sea. Scientists note that the section that calved was not held back by rock, so they are less worried that the loss of the calved section will result in the shelf’s wholesale disintegration in the near term. Some scientists even concede that the calved area could regrow to form a new ice dam that reinforces the shelf. However, the results of ice-calving and glacier-flow models predict that the shelf will continue to break apart over the course of years and decades.

Calving is a natural process driven, in part, by seasonal changes in temperature and the pressures associated with the build-up of compressional stress on the ice. Some studies argue that spring and summer foehns (warm dry gusty winds that periodically descend the leeward slopes of mountain ranges) have also contributed to the weakening of the ice. As investigations into ice shelf dynamics continue, such large iceberg calving events are often regarded as symptoms of climate changeassociated with global warming. While global warming may turn out to play a part in ice shelf calving events, scientists disagree on the role, if any, the phenomenon has played in recent developments on Larsen C.

Disintegration of Larsen Ice ShelfThe map shows the section of Larsen C that calved in July 2017.Encyclopædia Britannica, Inc.

Antarctica: A journey to the edge of a frozen continent

In early 2018 Reuters photojournalist Alexandre Meneghini travelled to the beautiful and vulnerable world of Antarctica.

The edge of Antarctica seen from aboveImage copyrightREUTERS

The trip, organised by Greenpeace, was to raise awareness of a European Union proposal to create a protected area in Antarctica, promoting a safe haven where marine life can thrive.

Penguins walking along a beachImage copyrightREUTERS

After a four-day voyage to reach the icy continent, the expedition encountered whales, penguins and enormous glaciers.

A penguin feeding a baby penguin by regurgitating food in to its mouthImage copyrightREUTERS

The proposed Weddell Sea Marine Protected Area (MPA) would cover some 1.8 million sq km (1.1 million square miles) of natural habitat for whales, seals, penguins and many kinds of fish.

If successful, it would be the largest protected area on the planet.

The tail of a whale seen sticking out the waterImage copyrightREUTERS

Starting in Punta Arenas, Chile, the crew set out to document the effects of climate change, pollution and fishing on native wildlife.

A large group of penguins on the beachImage copyrightREUTERS

“Antarctica itself is currently protected under the Antarctic Treaty, but there is a lot of scope for abuse of the waters around Antarctica,” said Tom Foreman, Greenpeace expedition leader. “So, the chance to protect these areas, which are so vital to such a huge number of species in so many ways, can’t be missed.”

As well as penguins, the group also encountered seals, seen here from a helicopter.

Seals on a beach in a photo seen from aboveImage copyrightREUTERS

The islands, bays and harbours visited by the group included: Curverville Island, Half Moon Bay, Danco Island, Neko Harbour and Hero Bay.

The edge of Antarctica seen from aboveImage copyrightREUTERS
A penguin walking on iceImage copyrightREUTERS

The crew also visited Deception Island, which is the caldera of an active volcano in Antarctica. A caldera is a large cauldron-like depression in the landscape that formed when the volcano previously emitted magma.

On the island were the remains of an old whaling factory and a small cemetery.

A derelict wooden buildingImage copyrightREUTERS
A pile of stones denoting a graveImage copyrightREUTERS
A lone penguin walking on a beach with a wooden building in the backgroundImage copyrightREUTERS
A derelict wooden boatImage copyrightREUTERS

“Contrary to what some may think, the Antarctic is full of life. Penguins, seabirds, and different species of seals and whales could be seen at all times,” said Alexandre Meneghini.

A group of penguins on iceImage copyrightREUTERS

“My encounters with the penguins were wonderful and joined my list of unforgettable moments.

“They do not see humans as predators and can surround you for hours if you do not move much. Along with my dog, I think they are the sweetest things in this world.”

Penguin footprints in snow and iceImage copyrightREUTERS

“As my long trip proved, Antarctica is remote from civilization. But it is not untouched. I hope my pictures reveal some of the region’s beauty.”

He added: “None of my pictures do justice to the experience of seeing these places first-hand.”

A glacier seen from aboveImage copyrightREUTERS
A glacier seen next to a land massImage copyrightREUTERS
Penguins walking along a iceImage copyrightREUTERS

All photos: Alexandre Meneghini/Reuters

Penguin super-colony spotted from space

 Media caption Largest population of penguins found in Antarctic Peninsula

Scientists have stumbled across a huge group of previously unknown Adélie penguins on the most northerly point of the Antarctic Peninsula.

Numbering more than 1.5 million birds, they were first noticed when great patches of their poo, or guano, showed up in pictures taken from space.

The animals are crammed on to a rocky archipelago called the Danger Islands.

The researchers, who detail the discovery in the journal Scientific Reports, say it is a total surprise.

“It’s a classic case of finding something where no-one really looked! The Danger Islands are hard to reach, so people didn’t really try that hard,” team-member Dr Tom Hart from Oxford University, UK, told BBC News.

Quadcopter aerial imagery of Adélie penguin breeding colonies on Heroina Island, Danger Islands, AntarcticaImage copyrightT.S.MCCHORD/H.SINGH/NU/WHOI
Image captionDrone pictures were one of the most efficient means of counting

The scientists used an algorithm to search images from the American Landsat spacecraft for sites of possible penguin activity.

Landsat does not return especially high-resolution pictures and so when the system flagged potential colonies, they had to be followed up with much sharper pictures for confirmation.

“And the sheer size of what we were looking at took our breath away,” said Dr Heather Lynch from Stony Brook University, New York.

“We thought, ‘Wow! If what we’re seeing is true, these are going to be some of the largest Adélie penguin colonies in the world, and it’s going to be well worth our while sending in an expedition to count them properly.”

Thomas Sayre-McCord (WHOI/MIT) and Philip McDowall (Stonybrook University) pilot a quadcopterImage copyrightC.YOUNGFLESH/SBU
Image captionThe drones flew grid lines over the penguin nests

But, as the name implies, the Danger Islands are notoriously difficult to reach.

Even in the austral summer, the ocean surrounding the archipelago is filled with the kind of thick sea-ice that ships try to avoid.

However, in December 2015, the team did manage to get on the ground to begin its count. And one of the most effective techniques was to deploy drones, which flew above the birds to make large mosaics of their nesting sites.

“The drone lets you fly in a grid over the island, taking pictures once per second. You can then stitch them together into a huge collage that shows the entire landmass in 2D and 3D,” explained Prof Hanumant Singh from Northeastern University.

Danger IslandsImage copyrightT.HART/OXFORD
Image captionThese are dangerous waters – hence the name of the islands

Once again, trained software was called upon to do the actual counting.

The survey revealed that the Danger Islands host in total 751,527 pairs of Adélie penguins, including the third and fourth largest colonies in the world.

The result is of major significance because it would appear the archipelago has somehow avoided the recent Adélie declines documented elsewhere on the peninsula, particularly on its western side.

Scientists suspect that decline has something to do with reductions in sea-ice, which is an important habitat for krill, the small crustaceans that form a key part of the penguin diet.

Adélie penguins jumping of iceberg, Danger Islands, AntarcticaImage copyrightR.HERMAN/LSU/SBU
Image captionSea-ice is important to these birds because it is a recruitment habitat for krill

Dr Hart commented: “On the West Antarctic Peninsula, Adelie and chinstrap penguins are declining pretty fast, while Gentoo penguins are increasing.

“It’s hard to know the causes. Clearly climate change and reduction in ice and krill play a part, but a decline in sea-ice also allows in shipping – fisheries in particular – which may exacerbate the problem.

“In the past we’ve looked at this on the West Antarctic Peninsula versus places like Elephant Island (further to the north). Finally getting into the Danger Islands and counting the penguins shows how robust populations are where the ice is intact.”

And Dr Lynch added: “The other point worth making is that these islands are right in the mix for a couple of marine protected areas that are being proposed.

“Whether they’ll be in or out, we don’t know but at least now the people making those decisions will understand how important this area is,” she told BBC News.

Dr Peter Fretwell from the British Antarctic Survey knows the team but was not involved in this study. He also uses satellites to identify and count animal groups.

“Despite our modern technologically advanced world there are still remote corners that we know very little about – usually because they are extremely difficult to get to,” he said.

“Modern satellites are fantastic tools for exploring and studying these hard-to-access places. I am sure that there are many other natural discoveries to be made using these ‘eyes in the sky’.”

In 1977 Argentina sent a pregnant woman to Antarctica in an attempt to claim partial possession of the continent

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Since 1940 Argentina and Chile have been in competition for ownership of Antarctica. Many other countries are involved in this “competition” for the territory, but no one truly owns the land or has actual sovereignty. Almost everyone dropped their claims after the Antarctic Treaty of 1959 was signed by 45 countries, which blocked any one nation from trying to take over the winter wonderland.

Argentina and Chile remained in this competition even after the Antarctic Treaty was signed. Both claim that the Antarctic Peninsula is a continuation of the Andes Mountains.

Esperanza Station, Hope Bay, Trinity Peninsula, on the northernmost tip of the Antarctic Peninsula. Photo Credit

Many still wonder why is it both countries want to own the Antarctic Peninsula. There are some reserves of coal, oil and other minerals, but no one knows exactly how much, and the mining and extracting of coal and oil is illegal.

In 1977 the Chilean President Augusto Pinochet visited the Antarctica to assert his country’s dominance in the region. This was perfectly normal compared to what the Argentinians did in retaliation. They used the most extreme action, and sent a pregnant woman to the barren and unpopulated continent of Antarctica in an attempt to stake a land claim there. She was supposed to give birth on the continent after being dropped at the Argentinian Esperanza Base.

Children, adolescents and teachers of the school of Esperanza Base receiving computers. Photo Credit

Silvia Morello de Palma became the first woman in recorded history to give birth on the continent. On January 7, 1978, Emilio Palma was born in Antarctica, the first person to be born there. After his birth, the Argentine government passed a law banning any maps of Argentina that didn’t include Antarctica.

Chile decided to play along and make this dispute even more absurd than it was. They sent recently married couples to their own Antarctic base in order to claim the first baby both conceived and born in the territory.

Correos de Chile office in Antarctica.

That started the baby boom in Antarctica. By 2009, eleven children had been born in Antarctica. Eight of them were born at the Argentinian Esperanza Base, while the other three were born at Chile’s Base Presidente Eduardo Frei Montalva. Chile’s first official Antarctican is Juan Pablo Camacho Martino, born on November 21, 1984.

The countries both sent couples a year at a time in their bids to secure their Antarctic territory.

By Goran Blazeski

The 106-year-old mystery of Antarctica’s Blood Falls finally unveiled: Living organisms found frozen in a lake hidden beneath the glacier

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Scientists throughout the world have been deeply puzzled for some time as to why the Taylor Glacier in Victoria Land of Eastern Antarctica gives the gruesome impression of what appears to be bleeding.

Named after its discoverer Griffith Taylor, who, during his expedition in 1911, first spotted this peculiar sight, the glacier is spread across the Taylor Valley. From time to time something rather strange occurs: an outflow of reddish water appears at its very end, pouring into West Lake Bonney below.

At first, scientists believed this strange phenomenon to be a direct result of tiny red algae that might be present in the water. However, further expeditions and scientific studies were carried out and water samples obtained from the “Blood Falls”.

Still, with expeditions being rather rare due the location being situated in one of the most remote and geologically exotic places in the world, and the results from them somewhat limited because samples often ended up lost or contaminated, nothing conclusive was reliably proved. That is until, in 2003, one study proved that the redness is due to the high amount of iron oxides, sulfates and salt present in the water.

Furthermore, the saltiness of the water led scientists to a conclusion that there must be free flowing salt water trapped somewhere beneath the huge plate of ice.

And as it turns out, there was. Hidden 400 meters deep beneath the glacier, a subglacial lake of unknown size containing extremely salty water was discovered. Located several kilometers from the outflow, the lake had been completely isolated from the outside world for almost two million years.

A team from the University of Alaska Fairbanks and Colorado College developed a new theory based on the findings and later conclusively proved its existence. They confirmed that not only did the glacier have a lake underneath it but also a free-flowing water system which allows the captive iron-containing liquid seawater to emerge through small cracks in the ice cascade, oxidize instantly and giving the water its bloody color.

The team concluded that somehow, due to an impressive perpetual hydraulic system which sees heat energy released by water freezing which in turn melts the surrounding ice, the water in the lake never really froze. They managed to confirm this using echolocation to track the water flow, kind of like the way bats use it in order to ‘see’ things around them.

At last, during the expedition of US National Science Foundation (NSF) in the Taylor Valley, fresh and uncontaminated samples were taken once again from Blood Falls to enable further studies of the water in the subglacial lake. And the results were simply astonishing.

Chemical and microbial analyses found that a rare subglacial ecosystem of autotrophic bacteria metabolizing sulfate and ferric ions instead of oxygen had developed into 17 different types of microbes, evolving completely independently, isolated from the outside world and any external evolutionary processes. According to geomicrobiologist Jill Mikucki from the University of Tennessee, the lead scientist of the project, such a metabolic process had never before been observed in nature.

Separated for an adequately long enough time, the ancient microbial population evolved in an entirely different way compared to similar marine organisms. This now offers to science one concrete explanation of how other microorganisms endured when the Earth was frozen in its entirety.

Not only that, the uniqueness of this evolutionary process, in a lake serving as a “time capsule” for life to evolve without oxygen for millions and millions of years, is spurring scientists to question the range of conditions in which life can exist. It also gives them a way to study the possibility of life in places such as Mars or Europa, the ice-covered moon of Jupiter, where till now the extremes of the temperatures on these planets excluded that possibility.

The NASA Astrobiology Institute hypothesizes that other planets could contain subglacial liquid water environments such as this. Moreover, they are enthusiastic about the prospect that those environments could be favorable enough for some elementary forms of life to start evolving or be preserved from times when conditions on those worlds were not so extreme. With this discovery, science can now rely on the premise that some forms of life might be better off at extreme depths, completely protected from ultraviolet and cosmic radiation, than exposed on the upper surface, and dig deeper in the search for life that might exist out there in the vastness of the universe.

 Martin Chalakoski

The baffling Piri Reis Map of 1513: It showed Antarctica centuries before discovery, but without its ice cap

 Late in 1929, Gustav Deissmann, a German theologian, was working in Istanbul at the Topkapi Palace Library. While cataloging antique items he found a gazelle-skin parchment in a stack of discarded items. This parchment had a map drawn on it, and Deissmann was amazed to see that it appeared to show the outline of South America. He rescued the parchment, which is now known as the Piri Reis Map.

The map he studied had been drawn and signed in 1513 by Turkish cartographer Hagii Ahmed Muhiddin Piri, also known as Piri Reis. In addition to being a cartographer, Piri Reis served in the Turkish navy, for which he held the rank of admiral. He stated that he had used 20 different maps and charts as his source documents. Eight of them were Ptolemaic maps (maps of the known world according to the 2nd century Hellenistic or Greek society), four were Portuguese maps, one was an Arabic map, and one was drawn by Christopher Columbus.

Fragment of the Piri Reis map.

 

 

World map of Cosa (1500). Cuba already appears as an island.

This simple piece of preserved gazelle skin has been the basis of intense controversy in the world of cartography. For one thing, the map appears to show Antarctica almost 300 years before it was discovered. Not only does it show Antarctica, but the continent is drawn as a land mass as it would have appeared before it was covered with its ice cap over 6,000 years ago.

Another hypothesis, less accepted, which attempts to correlate the American outline map of Piri Reis with coastal Venezuela and Brazil.

This controversy was precipitated when Professor Charles Hapgood published, in 1965, his theory about Antarctica in the book Maps of the Ancient Sea Kings. Professor Hapgood, based at the University of New Hampshire, had studied the Piri Reis Map with his students and found several things that they could not explain. Not only was there the issue of Antarctica without its ice cap, but they noticed that the map was drawn using the Mercator Projection, a methodology not used by European cartographers until the late 16th century.

Hypothesis that attempts to correlate the lower boundary of the Piri Reis map of the coast of Argentine Patagonia and the Falkland Islands.

Flemish cartographer Gerardus Mercator devised the cylindrical map projection in 1569. The Greeks had the ability to create cylindrical maps utilizing their knowledge of the Earth as a sphere, along with the astrological and geometric skills to calculate latitude and longitude. The accuracy of the Mercator Projection was not absolute until the chronometer was invented in 1760.

The use of Mercator Projection on the Piri Reis Map could possibly be explained by his use of Greek maps in the creation of his drawing, but there was no explanation for the inclusion of Antarctica without the ice cap.  Professor Hapgood and his students theorized that the Piri Reis map had to have been based on information older than 4,000 BCE. This is long before any known sophisticated civilizations or any well-defined languages; the map introduces the theory of an ancient civilization that had the skills to navigate the world’s oceans, and accurately chart the lands they visited.

Professor Hapgood went on to state that the topographical representation of the area inland from the coast was so accurate that this ancient super-civilization had to have aerial capabilities in addition to their nautical and cartographic abilities. This naturally led to a theory of an alien civilization or one based on the lost city of Atlantis.

Cristóbal Colom landed on Hispaniola.

Those skeptical of the Piri Reis theories point out that the map is a fair representation of the coastline of South America, with modern features of the coast and interior shown. If this is not simply the coast of South America, that would mean South America and Antarctica were joined at Uruguay and that Argentina is a recent addition to the land mass. This argument infers that what is thought to be Antarctica on the Piri Reis Map is the lower portion of the South American continent.

Professor Hapgood then theorized that the Earth underwent a shift in its axis around 9,500 BC, which displaced Antarctica and moved it thousands of miles to the south, where it became covered in ice. Evidence shows that this phenomenon would have been impossible and did not happen.

The jury is still out on the question of whether the Piri Reis Map shows Antarctica or not. If you subscribe to the idea that this portion of the map is Antarctica without its ice cap (which has appeared on other maps), then you must believe that an ancient civilization that had advanced navigational skills existed and produced accurate maps of the globe. If you believe that this depiction is of the lower coast of South America, then you will probably scoff at the idea of an ancient advanced civilization. Until there is absolute proof to support one or the other theory, the arguments will continue.

By Ian Harvey