Remote Antarctic Trek Reveals A Glacier Melting From Below

The surface tower at a drill site, under construction during blistering Antarctic winds. Data from instruments, deployed through 450 meters of ice, is transmitted from the tower by satellite back to the Naval Postgraduate School.

Image courtesy of Tim Stanton The surface tower at a drill site, under construction during blistering Antarctic winds. Data from instruments, deployed through 450 meters of ice, is transmitted from the tower by satellite back to the Naval Postgraduate School.

Image courtesy of Tim Stanton

Scientists watching Antarctica's Pine Island Glacier from space have noticed with some alarm that it has been surging toward the sea.

If it were to melt entirely, global sea levels would rise by several feet.

The glacier is really, really remote. It's 1,800 miles from McMurdo, the U.S. base station in Antarctica, so just getting there is a challenge. Scientists have rarely been able to get out to the glacier to make direct measurements.

"This was a granddaddy of a problem," says Tim Stanton, oceanography research professor at the Naval Postgraduate School in Monterey, Calif.

Stanton not only wanted to get to it, he wanted to get to it with 20,000 pounds of gear, so they could drill into it.

The Naval Postgraduate School team deploys ocean monitoring instruments through a bore hole into the ocean cavity below.

Image courtesy of Tim Stanton The Naval Postgraduate School team deploys ocean monitoring instruments through a bore hole into the ocean cavity below.

Image courtesy of Tim Stanton

Stanton and about a dozen colleagues spent several years planning this mission, which involved multiple aircraft and remote support camps. In fact, they took four trips to Antarctica before they finally succeeded.

It wasn't just getting there that was hard. Bill Shaw, a colleague of Stanton's, says Antarctica has its own way of serving up trouble.

"You're in your tent sleeping, and you start to hear things flapping and then you wake up to find that all your neatly piled batches of gear are now covered in several feet of snow," Shaw says. "You're going to spend the next several days digging it out and getting going again."

That happened more than once during their seven weeks out on this remote piece of ice. They chose this spot because the glacier here is actually being undercut by ocean water, which flows below it.

The team's challenge was to drill down through the ice sheet, which is twice as thick as the Golden Gate Bridge is tall. Melting those holes involved heating up a metal rod and circulating hot fluid through hoses to the rod, as it gradually ate its way down through the ice.

"Everybody was shlepping hose," Stanton says. "They needed lots of support, so that's what we did during the drilling phase. As soon as the hole was through, we immediately started deploying instruments."

In particular, Stanton wanted to measure the currents flowing right under the ice sheet. He wanted to test how salty the water was, and to find out how quickly the ice was being eaten away by the comparatively warm seawater. They also grabbed a sample of the mud from the seafloor below.

"To see what's down there is quite remarkable, because I can assure you, nobody else on this planet's ever touched the mud before us, underneath an ice shelf like that," he says.

Their instruments showed that meltwater from the glacier was flowing rapidly toward the open ocean, and cutting into the ice above as it went.

"I was surprised by how much like a river this was. It's a river, but instead of eroding a channel, it's melting a channel," Shaw says.

And it turns out that channel is melting very fast. As they report in Science magazine, the ice in that channel was disappearing at the rate of 2 inches a day. Stanton said their measurement is consistent with what scientists had inferred from satellite measurements.

"Don't forget, this happens day in and day out," he says. "We saw no changes over the 35 days that we were reporting on in this paper. It's a phenomenally high melt rate compared to what we observe in the Arctic, for example."

At the moment, it's contributing a tiny amount to rising sea levels. But the melting has been accelerating in recent years, and if it keeps accelerating, in the very long run, the Pine Island Glacier could add several feet to global sea levels.

The results are sobering, but Stanton says when the drilling system finally punched through the ice and he was able to position his instruments, he felt he'd conquered this grandaddy of a problem.

"That was remarkably satisfying," he says. "It really had been a long, long road."

With luck, those instruments will continue to run for another two or three years — and send their data back via satellite to Stanton and his colleagues, in the cozy confines of their labs.

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Proposal to Protect Antarctic Waters Is Scaled Back

The Ross Sea marine protected area that the two governments proposed last year was to have set aside about 875,000 square miles of the Southern Ocean where commercial fishing would be sharply limited. The area’s relatively pristine ecosystem is crucial to the survival of thousands of species, including whales, seals and penguins, as well as the small fish and crustaceans on which they depend.

On Friday, though, New Zealand announced that the overall size of the proposed reserve was being reduced by 40 percent to gain the support of member nations on the Commission for the Conservation of Antarctic Marine Living Resources, the international body that sets conservation policy for the Southern Ocean, of which the Ross Sea is a part. Commission delegates are scheduled to meet next month in Hobart, Australia, to consider the proposal.

It was clear in July that the American-New Zealand proposal was on shaky ground after a commission meeting in Bremerhaven, Germany, broke up without agreement. Supporters of the proposal expected delegates there to work on ironing out details, and were stunned when Russia and Ukraine raised legal and procedural questions that halted the discussion, and questioned the commission’s authority to create such reserves. Norway, China and Japan led other fishing nations in calling for smaller reserves, and for “sunset clause” provisions that would allow for the possibility of eventual commercial exploitation of the areas.

Most of the fishing activity in the Ross Sea now is directed at the slow-maturing Patagonian toothfish, often marketed as Chilean sea bass. But there is growing interest in harvesting krill, the tiny creatures that are a pillar of the Southern Ocean ecosystem, and many fishing nations do not want to seal off any future possibilities as fish stocks elsewhere in the world are depleted.

Nongovernmental organizations have accused Washington and Wellington of caving in without a fight. The Antarctic Ocean Alliance, a coalition of 30 environmental groups, said on Monday that the scaled-down version of the proposal was a “tactical mistake and a significant retreat for Southern Ocean protection.”

Andrea Kavanagh, a spokeswoman for the Pew Charitable Trusts on Antarctic issues called it “baffling.” The decision to make such a large concession before the Hobart meeting has even begun, she said, means that by the time a deal is reached, the reserve might be only half its original size.

“What is so disturbing is that this is the new starting line,” she said, “and the permanence of it is now up for negotiation.”

Evan T. Bloom, the head of the American delegation to the Antarctic conservation commission, said that the most important parts of the initiative remained intact and that the reserve would still be the world’s largest.

“I know there are a number of stakeholders who are particularly concerned about the changes we’ve made,” Mr. Bloom said, “but we think it’s necessary to take into account the views of members of the commission and the scientific committee.”

A concurrent proposal, championed by Australia, France and the European Union, for a network of seven protected areas in the eastern Antarctic region is also being revised for the Hobart meeting, though the changes that have been made so far relate to how they will be established, not their sizes.

Nongovernmental groups have accused the Russians of negotiating in bad faith. They point out that many of the nations that are now balking at creating marine reserves had pledged in 2010 at a United Nations conference in Nagoya, Japan, to set aside 10 percent of the world’s oceans for conservation by 2020. Currently, less than 1 percent is protected, and the goal is almost certain to go unmet.

Dmitry Kremenyuk, the head of the Russian delegation to the conservation commission, said accusations that Russia had blocked progress “would not be correct.” He acknowledged that his country had raised scientific and legal questions about the basis for the reserves, but he said other countries had also expressed misgivings. The objections raised in Bremerhaven were part of “a standard way of negotiating,” he said.

Mr. Kremenyuk suggested that the revised Ross Sea proposal might meet with a better reception in Hobart, and that the European-Australian proposal for the eastern Antarctic would also have to be revised.

“They’ll have to rearrange their priorities, and then it might work,” he said. “Cast away the zones that are less significant, and retain the top priority ones.”

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