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Thursday, December 15, 2011

100 years on, Antarctic science going strong

Image: NASA aircraft
Jefferson Beck / NASA
A NASA aircraft, part of the agency's IceBridge mission, banks over an ice shelf jutting out from western Antarctica during an October 2011 data-gathering flight.
 
By
OurAmazingPlanet
12/14/2011 
 
eek, dozens of brave revelers — the prime minister of Norway among them — are converging on the South Pole to celebrate the historic trek of Norwegian explorer Roald Amundsen, the first human to set foot there on Dec. 14, 1911.
Yet in an ironic twist, some might argue that it is the runner-up in the grueling contest whose legacy has proved more lasting.

British explorer Robert Falcon Scott, who reached the pole a month after Amundsen, died on his return march, unable to escape the tightening noose of the Antarctic winter. And although his oft-maligned tactics proved, in part, to be his undoing, Scott's insistence on bringing scientists on his expedition — at great cost to himself — helped spark a tradition of scientific inquiry in Antarctica that endures to this day, according to Ross MacPhee, curator at the American Museum of Natural History in New York, and author of the book, "Race to The End: Amundsen, Scott, and the Attainment of the South Pole" (Sterling Innovation, 2010).
"Every scientist working in Antarctica today owes Scott something," MacPhee told OurAmazingPlanet in September.

Science is now one of the primary drivers of human activity on the continent.
Each year, when the perpetual daylight of austral summer begins, droves of scientists descend on Antarctica to study its biology, drill deep into its ice, and send airplanes soaring overhead to image what lies underneath its glaciers.
Nearly 30 countries operate more than 80 research stations around the continent, according to 2009 numbers from the Council of Managers of National Antarctic Programs.
A flurry of work is now under way on and around the continent.

Image: Robert Falcon Scott
Courtesy of Charles Leski, Leski Auctions.
Robert Falcon Scott in the expedition's well-stocked hut. 
 
Charismatic fauna 

Some scientists come to study the unique crowds of marine life that gather near the nutrient-rich waters off the Antarctic coast in the comparatively balmy summer. Penguins may be the most beloved of the local animal pantheon, but studying these birds is nothing like a Disney movie.
"Penguins are not cuddly at all. They're really very strong and very feisty, and they don't like to be picked up, which we try not to do," said David Ainley, a marine ecologist who has been studying Adélie penguins in Antarctica since the late 1960s.

For decades, Ainley, now with the California-based ecological consulting firm H.T. Harvey & Associates, has researched why penguin populations are changing; some colonies have grown, others have shrunk. He said he's interested in answering a very basic question about life on our planet — how do animals cope with their environment? — and that penguins are the ideal research subject.
"They're fairly large so you can put instruments on them and record their behavior," Ainley told OurAmazingPlanet just hours before he boarded a plane headed south.

Image: Adelie penguins
Dr. Robert Ricker, NOAA / NOS / ORR
Don't ask these guys to tap dance. Adelie penguins in Antarctica.

In addition, he said, they're pretty easy to find. "Penguins are very visible," Ainley said. "In the Antarctic they don't have any place to hide. They don't live in burrows, and it's daylight all the time."

Biological time trip 

While Ainley and his team spend their days on the rocky slopes of Antarctic islands, other scientists spend the austral summer on ships. David Barnes, with the British Antarctic Survey, spoke with OurAmazingPlanet from the RRS James Ross, a research vessel parked near the Antarctic Peninsula, the long finger of land that points toward South America.

Barnes said that his research focuses on trying to unlock the secrets of Antarctica's icy past, specifically how the reach of the massive West Antarctic Ice Sheet has changed from age to age. Scientists know it has been larger than it is now, and some suspect it has been smaller than it is now, but anything more exact is difficult to pin down.

"The problem is that every time there's an ice age it's wiped out everything — so we don't really know where the last ice sheet got to," Barnes said. But there is another way to peek into the Antarctic's past: "Where we can't get good signals from glaciology or geology, biology has a cunning way of stepping in," he said.

Image: Pine Island glacier
Eric Rignot, JPL 
 
This is an aerial, close-up view of the floating section and ice front of Pine Island glacier, November 2002.
Barnes looks at the genetic makeup of sea creatures around western Antarctica to determine how long populations have been isolated from one another by the ice.
"Genetics preserve a connection between species and populations, so by looking around Antarctica at various depths we can get an idea of whether that area used to be underneath an ice sheet," Barnes said.
That information can, in turn, help scientists figure out how the West Antarctic Ice Sheet behaved in climates past, and how it might behave in our warming world.

Ice life 

Still other scientists will spend the austral summer living on the ice itself. Robert Bindschadler, a glaciologist and scientist emeritus with NASA, along with a small team of researchers, will spend six weeks sleeping in small tents on a floating plain of ice — the Pine Island Glacier ice shelf — the outlet of one of the largest and fastest moving glaciers in Antarctica.
Ice shelves, which ring the continent, appear to be a key player in the increasing and alarming rate at which glaciers in the West Antarctic Ice Sheet are melting and raising sea levels in recent years, Bindschadler said. But getting direct observations of how this is happening is a challenge. Satellite imaging and data provide some details, but the continent is remote, and its long, brutal winter permits scientists to work there for only about three months a year, [ Stunning Photos of Antarctic Ice ]

Observations indicate that comparatively warm ocean water is lapping away at the ice shelves, which, as they weaken, allow glaciers to slide into the sea at a faster and faster clip — yet the direct mechanisms remain hidden from view.
"Satellites have taken us really far, but they can't give us the answers to what's going on underneath," Bindschadler said. To that end, his team will spend its days drilling several  holes through nearly a third of a mile (500 meters) of ice to drop sensors into the sea below to measure variations in temperature and currents.
Some scientists conduct their research from the air, working aboard planes equipped with imaging technology that can peer beneath the ice.   NASA's IceBridge project focuses on the western half of the continent, while other international collaborations focus on the far larger yet more stable eastern half.

Ice work if you can get it 

Other research must be done on the ground. Scientists are drilling deep into the ice to collect signatures of past climate trapped inside, or looking for microbes that dwell in it. The race to drill down to the more than 200 freshwater lakes that pepper the continent is another tantalizing quest..
Some researchers work in Antarctica because the frigid continent, free of a native human population or meddling flora and fauna, provides a kind of natural laboratory.
"In most ecosystems you have plants all over the place, and they do a lot of things to complicate the system," said Byron Adams, a professor at Brigham Young University who studies the nematodes and other tiny creatures that are found in the few patches of ice-free soil in the Antarctic.

Image: Outside McMurdo Station
Rob Jones, National Science Foundation
 
Flags fly outside McMurdo Station, one of three United States research stations in Antarctica and the largest.
Still other researchers take advantage of the high altitude and clear air to peer through telescopes into distant space and the early universe.
At about 1.5 times the size of the United States, Antarctica has plenty of scientific real estate to go around.
At the heart of much of the research is the question of how the continent's ice is responding to climate change. Antarctica is home to some of the most dramatic effects of climate change seen anywhere on Earth, from melting glaciers to increasing winds to warming temperatures. The Antarctic Peninsula has warmed several times faster than the global average rate.

"We're asking really fundamental questions about how ecosystems respond to a changing climate, and ultimately the goal is to be able to make predictions about this," Adams told OurAmazingPlanet.
Despite the challenges — bone-chilling winds, constant sunlight, extreme isolation and ever-changing weather — many scientists said working in Antarctica is worth the hardship and the long hours spent packing as much work into an expedition as possible. Although it's not for everyone, they cautioned, the work can be deeply satisfying, breeding a sense of camaraderie that can last a lifetime.

"When you're out in the deep field, and you're only living with what you brought, and the plane turns and leaves, that's the Antarctica I prefer," Bindschadler said. "You really are in a different world."

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