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Pap Test, a Mainstay Against Cervical Cancer, May Be Fading
By ANDREW POLLACK, The New York Times, January 16, 2007
The big news in the war on cervical cancer is the new vaccine recently approved to prevent the disease. But another major change that will affect millions of women is also under way, though more slowly and quietly.
The Pap smear, an annual ritual for many women and the mainstay of cervical cancer prevention for more than half a century, may start to fade in importance.
It will not disappear for many more years, if ever. But a newer genetic test that detects human papillomavirus, or HPV, which causes cervical cancer, is starting to play a bigger role in screening. And other genetic tests are being developed. At the least, some experts say, women will no longer need Pap smears as often.
“We can potentially change the entire cervical screening paradigm,” said Dr. Thomas C. Wright, a professor of pathology at Columbia University Medical Center who is also a consultant for Roche, which is developing a genetic HPV test.
The new vaccine could also deal a longer-term blow to Pap testing, which works by detecting abnormal cells from the cervix that could be on their way to becoming cancerous. It is not that women would no longer need screening because they had been vaccinated. The vaccine, approved only for girls and women 9 to 26 years old, does not protect against all strains of HPV that cause cancer.
If a precancerous lesion is present, the Pap test will detect it only 50 percent to 80 percent of the time. Pap testing is effective only because it is done often; a lesion can take 10 years to turn into a cancer, so a yearly test will probably find it in time.
As more women get the HPV vaccine, however, the number of lesions will decline, making the Pap test more costly per cancer case detected. And with fewer problems to detect, said Dr. Eduardo L. Franco, a professor of epidemiology and oncology at McGill University, the technicians who read Pap smears may lower their guard — and their accuracy.
Pap testing “is going to break down in a world in which vaccination decreases the prevalence of lesions,” said Dr. Franco, who said he had done some minor consulting for genetic test developers. Referring to the accuracy of Pap testing, he added, “It’s already bad enough, and it’s going to get worse.”
But Pap testing has its strong defenders, who question the value of the genetic test for HPV. Some gynecologists say having women come for annual Pap testing brings them in for other needed examinations. And there is a huge industry built up to provide the screening.
“The perception is that the annual Pap smear drives volume,” said Dr. Walter Kinney, a gynecological oncologist at Kaiser Permanente, the health maintenance organization. “I don’t see anyone raising their hand volunteering to give that up.”
At Kaiser, where doctors’ pay does not depend on customer volume, the genetic HPV test is offered with Pap testing to every woman 30 and older. If both tests are negative, a woman does not come back for further screening for three years. The savings from less frequent screening more than pay for the extra cost of the HPV test, Dr. Kinney said.
Kaiser’s testing laboratory in Berkeley, Calif., processes 300,000 to 500,000 cervical specimens a year. A robotic arm rapidly retrieves particular specimens from cold storage for testing and disposes of others when they are no longer needed.
The most recent guidelines from the American College of Obstetricians and Gynecologists, issued in 2003, suggested that some women over 30 do not need annual Pap tests, but many doctors and patients have resisted that idea.
“Sometimes you advocate that strategy, but the woman comes back the next year almost demanding the Pap smear,” said Dr. Juan Felix, a professor of pathology and of obstetrics and gynecology at the University of Southern California. “Women have been sort of mentally trained to come to get their annual test.”
Pap testing is named for Dr. George N. Papanicolaou, who developed the test at Cornell Medical School. It started to become widely used in the 1950s.
Cells are scraped from the surface of the cervix, spread on a microscope slide and examined for abnormalities that could indicate a precancerous lesion. If found and confirmed by further examination, the lesions can be removed by any of several techniques.
Pap testing has cut cervical cancer rates by 75 percent or more in nations with thorough screening. In the United States, there are now about 10,000 cases of cervical cancer each year and 4,000 deaths. More than half the cases are in women who do not undergo screening.
“It is one of the greatest public health interventions in terms of sheer success and lives saved,” said Philip E. Castle, an expert on cervical cancer screening at the National Cancer Institute.
But while successful, Dr. Castle said, Pap screening is “not very efficient,” costing billions of dollars a year. And it does miss cancer cases. A study of women with cervical cancer, conducted among members of seven health plans and published in The Journal of the National Cancer Institute in 2005, found that 32 percent had had one or more normal Pap tests in the three years before the diagnosis.
B. K. Cockrell, 57, a homemaker in Troup, Tex., was one woman who got cancer despite a series of normal Pap tests. In 2005, her gynecologist, Dr. A. Jay Staub of Dallas, also began giving the HPV genetic test, which gave a positive reading. Further examination showed that Ms. Cockrell had cancer, which was caught early enough to be removed by a hysterectomy without the need for chemotherapy or radiation.
“I believe I would be extremely ill today” if not for the HPV test, she said.
A newer form of Pap testing called liquid cytology, which spreads the cells more evenly on a slide, is said by some cytologists to be more sensitive, though some published studies contradict that.
But Pap testing has other problems as well. Of the 50 million to 60 million tests done in the United States each year, as many as two million are classified as ambiguous, possibly a lesion and possibly not. Such results require further testing, like colposcopy, an uncomfortable procedure in which the cervix is examined with a magnifying device, and biopsy, which can be painful.
The HPV genetic test looks for the DNA of 13 of the cancer-causing strains of the virus. Experts say this test can detect more than 90 percent of precancerous lesions. It is also easier to automate and far less likely to produce ambiguous results.
The samples are taken the same way as for a Pap test, meaning women still need to get into stirrups. But since the genetic test is less prone to error, experts say it is possible that in the future women will be able to take their own samples.
The test was first approved by the Food and Drug Administration in 1999, and its use has grown steadily, partly spurred by advertising by the test’s manufacturer, Digene. The company, based in Gaithersburg, Md., says about seven million Americans are getting the test each year, which is one-fifth of those it believes would be eligible. With Merck now calling attention to the role of HPV in its advertisements for its new vaccine, Digene executives expect interest in their test to grow.
Some experts say that since the HPV test catches more lesions than Pap, it would be cost-effective to make it the primary test, with Pap testing used only on the women who test positive for the virus.
“HPV testing as the stand-alone primary screening technology represents the scientifically obvious next step,” F. Xavier Bosch of the Catalán Institute of Oncology in Barcelona, Spain, wrote last August in a supplement of the journal Vaccine on the future of cervical cancer prevention.
But some experts say the HPV test is not ready for that.
One problem is that HPV testing costs $50 to more than $100, compared with as little as $20 for a Pap test. More significant, many, if not most, sexually active women will be infected with HPV at some point. But in most cases, particularly for younger women, the immune system dispenses with the virus.
That is why even those who advocate using HPV testing as the primary screen, or using it alongside Pap testing, do so only for women over 30 or 35, when the viral infection is less likely to be transient. (The HPV test is approved for two uses: to help resolve an ambiguous Pap test or to use in conjunction with Pap screening for women 30 and over.)
Dr. George Sawaya, an associate professor of obstetrics, gynecology and reproductive sciences at the University of California, San Francisco, says about 2,500 to 3,000 cervical cancer cases in the United States each year are in women with normal Pap tests. While use of the HPV test instead of the Pap as the primary screen may further reduce that number, “we have to make sure we are not dragging along tens of thousands of women who will have positive tests but no disease,” he said.
Some of those women would be subject to unnecessary biopsies and even to removal of lesions that would never turn cancerous, he said. The removal operations have risks of their own, he added, potentially raising the chances a woman will have premature deliveries in the future.
Wider use of HPV testing would also mean telling millions of women that they have a sexually transmitted disease, causing unnecessary stress. “Everybody presumes they are dirty when they are told they have something like this,” said Dr. Abbie Roth, an obstetrician and gynecologist at Northwestern Memorial Hospital in Chicago. “Everybody universally cries when they get that information.”
Digene says it hopes that European countries, which place more limits on medical spending than the United States, will make HPV testing the standard in place of the Pap. European experts disagree on whether that will happen.
But Pap testing is likely to be displaced in developing countries, which account for more than 80 percent of the roughly 500,000 new cases of cervical cancer and 275,000 deaths each year. Those countries cannot do efficient Pap screening for lack of laboratories and technicians and difficulty in getting women, who might have to walk miles to a clinic, to come for testing every year.
In the developing world, Pap testing has had “basically no impact on cervical cancer rates in any country, ever,” said Jacqueline Sherris, a strategic program leader for reproductive health at PATH, a nonprofit organization in Seattle.
PATH is working with Digene to develop a simpler and cheaper version of the HPV test for developing countries. Women might be tested only once or twice during their 30s but would get fairly good protection, Ms. Sherris said.
Still other tests are in development. One would determine the specific strain of HPV infecting a woman. Types 16 and 18 account for most cancers (and are the cancer-causing types targeted by the new vaccine). So having one of them would be considered more worrisome.
Yet another test would look for the activation of two genes, called E6 and E7. Such activation is believed to be required for a precancerous lesion to turn into cancer.
“Looking forward,” said Dr. Wright of Columbia, “the molecular tests are becoming so good that we can see a time when cytology is no longer used as the primary screening test.”
Huts have been reconstructed near the site as a heritage center.
Humble Brass Was Even Better Than Gold to a 16th-Century Tribe in Cuba
By JENNIFER PINKOWSKI, The New York Times, January 16, 2007
Because of its otherworldly brilliance, the 16th-century Taíno Indians of Cuba called it turey, their word for the most luminous part of the sky.
They adored its sweet smell, its reddish hue, its exotic origins and its dazzling iridescence, qualities that elevated it to the category of sacred materials known as guanín. Local chieftains wore it in pendants and medallions to show their wealth, influence and connection to the supernatural realm. Elite women and children were buried with it.
What was this treasured stuff? Humble brass — specifically, the lace tags and fasteners from Spanish explorers’ shoes and clothes, for which the Taíno eagerly traded their local gold.
A team of archaeologists from University College London and the Cuban Ministry of Science, Technology and Environment came to these conclusions by analyzing small brass tubes found in two dozen burial sites in the Taíno village of El Chorro de Maíta in northeastern Cuba, according to a recent paper in The Journal of Archaeological Science.
The graves mostly date to the late 15th and early 16th centuries, when waves of gold-hungry conquistadors landed on Caribbean shores. Within decades, the Taíno, like their neighbors the Carib and the Arawak, were largely wiped out by genocide, slavery and disease.
But the archaeologists say this is not the whole picture. Their research — the first systematic study of metals from a Cuban archaeological site — focuses on one of the few indigenous settlements ever found that date from the period after the arrival of Europeans. The scientists say the finds add important detail and nuance to a history of the Caribbean long dominated by the first-person reportage of the Europeans themselves.
“It’s certainly true that the arrival of the Europeans was in the short term devastating,” said Marcos Martinón-Torres of University College London, the project’s lead researcher. “But instead of lumping the Taíno in all together as ‘the Indians of Cuba who were eliminated by the Spaniards,’ we’re trying to show they were people who made choices. They had their own lives. They decided to incorporate European goods into their value system.”
Brass first came to the Americas with Europeans. While a few brass artifacts have been found elsewhere in the Caribbean, no one knows when and how they were acquired. In contrast, El Chorro, first excavated in the mid-1980s, is one of the best-preserved sites in Cuba, and its artifacts have a clear archaeological context.
Training X-rays and microscopes on a half-dozen pendants, Dr. Martinón-Torres and a Cuban archaeologist, Roberto Valcárcel Rojas, determined the metals’ bulk chemical composition. It was a mixture of zinc and copper — the elements of brass.
They then used a scanning electron microscope to find the pendants’ unique geochemical signature. All came from Nuremberg, Germany, a center of brass production since the Middle Ages.
The few other metal artifacts from the cemetery — pendants made from a gold-copper-silver alloy — probably came from Colombia, where the Taíno are thought to have originated. Only two tiny gold nuggets, of local origin, were found.
Sixteenth-century portraits in places like the Tate Gallery held further clues. Many subjects wear bootlaces and bodices fastened with objects strikingly like those found in the graves. Similar objects have been excavated from early colonial settlements, including Havana and Jamestown, Va.
European accounts said the Taíno traded 200 pieces of gold for a single piece of guanín, of which brass was the highest form. Yet the residents of El Chorro may not have considered the trade unfair, said Jago Cooper, a field director for the project. In fact, access to European brass may have increased the power of local chieftains, hastening the transition from an egalitarian society to a hierarchical one.
The finds from El Chorro suggest that interaction between the Taíno and the Europeans may have been more varied than once thought.
“Large European materials being incorporated into their culture, and exotic materials being used to reflect Taíno beliefs — it’s new, important evidence for what was happening during contact,” said William F. Keegan, an archaeologist at the University of Florida and the co-editor of The Journal of Caribbean Archaeology, who was not involved in the research. “There’s been a tendency to assume the Taínos quickly disappeared due to European diseases and harsh treatment by the Spanish, but there’s increasing evidence that the culture continued to be vibrant until the middle of the 16th century.”
Some of that evidence comes from another site in Cuba: Los Buchillones, a coastal settlement about 200 miles west of El Chorro de Maíta. First excavated in 1998 by a Cuban-Canadian team, Los Buchillones is the site of the only known intact Taíno house. In the last decade, continuing study of the site and the surrounding region by Mr. Valcárcel Rojas and Mr. Cooper has revealed a community with trade networks all over the Greater Antilles that survived into the Spanish colonial period in the early 17th century. Clearly, they would have known about Europeans’ presence, but chose to avoid contact, unlike El Chorro’s chieftains. It may have kept them alive longer.
Together, the sites hint at an array of tactics not documented by the Europeans. “Most accounts seem to be based on the idea that Europeans ‘acted’ and Taíno ‘reacted,’ ” said Elizabeth Graham of University College London, who with her husband, David Pendergast, first excavated Los Buchillones. “In the case of El Chorro de Maíta, the Taíno were clearly being proactive.”
The finds at El Chorro also help to fill a hole in the study of the Caribbean past created by Cuba’s political isolation. Archaeology of the island has been little known outside of its borders since the 1959 revolution. Very few foreign archaeologists have dug there, and the few field reports published by Cuban archaeologists, mostly trained by Soviet scholars, are difficult to get outside the country.
In recent years, there have been efforts to bring Cuban archaeology out of the long shadow cast by the 45-year-old United States sanctions. In 2005, the scholarly volume Dialogues in Cuban Archaeology assembled a dozen English-language reports in one place. (In it is a paper Mr. Valcárcel Rojas co-wrote about El Chorro de Maíta.) The relatively new Journal of Caribbean Archaeology currently has its first Cuban paper in peer review.
For most American archaeologists, papers published by their international colleagues are about as close as they are going to get to Cuba these days. Since 2004, the Bush administration has greatly tightened restrictions on educational travel to Cuba; programs under 10 weeks are now prohibited. Last summer, Florida went a step further, banning public universities from spending money on research in countries the State Department considers state sponsors of terrorism, including Cuba. Both sets of regulations are being challenged in court.
Last spring, Mr. Valcárcel Rojas was denied a visa to attend the annual Society for American Archaeology conference in Puerto Rico. Dr. Martinón-Torres and Mr. Cooper presented the research — which received Cuba’s highest academic prize — without him.
Still, the British-Cuban team is seeking a three-year grant in hopes of uncovering the trade and social networks that connected El Chorro’s inhabitants — in particular, the effects of the brass-gold trade on those connections. And there is European behavior to puzzle out, too.
“We would expect the Europeans to load up with brass in their cargos, but we haven’t found that brass in Cuba,” Dr. Martinón-Torres said. “It’s possible it hasn’t been recognized by archaeologists. We expect if both sides were happy with this exchange, there must be more evidence of it.”
Archaeological digs at Tell Hamoukar in Syria have yielded the remains of a body, possibly a war casualty.
Ruins in Northern Syria Bear the Scars of a City’s Final Battle
By JOHN NOBLE WILFORD, The New York Times, January 16, 2007
Archaeologists digging in Syria, in the upper reaches of what was ancient Mesopotamia, have found new evidence of how one of the world’s earliest cities met a violent end by fire, collapsing walls and roofs, and a fierce rain of clay bullets. The battle left some of the oldest known ruins of organized warfare.
The excavations at the city, Tell Hamoukar, which was destroyed in about 3500 B.C., have also exposed remains suggesting its origins as a manufacturing center for obsidian tools and blades, perhaps as early as 4500 B.C.
The two discoveries were made in September and October and announced yesterday by the Oriental Institute of the University of Chicago and the Syrian Department of Antiquities. The site is in northeastern Syria, less than five miles from the Iraqi border.
The proximity to Iraq is not insignificant. Driven out of Iraq by the war and political turmoil, Western archaeologists who specialize in the first urban civilization that flourished in Mesopotamia have had to shift their digging to the northern fringes of the Tigris and Euphrates river valleys, in Syria and Turkey.
As a result, archaeologists are gaining a broader perspective on a transformative period in antiquity that saw the rise of the first cities, specialization in work, stratification of society and eventually, the first known writing. While the more thoroughly studied urban centers in southern Iraq may have been earlier and more powerful city-states that coalesced into empires, those in the north were not as peripheral as once assumed. Some of them developed robust cultures more or less independent of the south. Trade between the two regions was common, and so apparently was conflict.
“We are learning that what was happening in the north cannot be explained as just simple expansion of southern culture,” said Clemens Reichel, a University of Chicago archaeologist who is excavating the battle ruins at the site. Guillermo Algaze, an archaeologist at the University of California, San Diego, who specializes in north-south relations in ancient Mesopotamia, said, “our interpretations are going to shift,” when these new findings are published.
Expanded excavations at Tell Brak, Habuba Kabira, Hamoukar and elsewhere in northern Syria, Dr. Algaze said, have revealed that some northern cities were larger at an earlier time than was expected. And ample evidence is being found for specialized industries like the obsidian works at Hamoukar.
“We are formulating questions to ask when we get back in southern Iraq,” Dr. Algaze said.
Almost no field work has been done in Iraq since 1990, leaders of Mesopotamian archaeology say, and concern is mounting that war and looting have left prized sites in disarray. New hydroelectric projects are another spur to stepped-up excavations in Syria and Turkey. Archaeologists are rushing to dig before ruins are inundated by dammed rivers.
Research at Hamoukar has been under way since 1999. The Chicago-Syria team has now determined that the 40-acre heart of the city was surrounded by a 10-foot-thick wall. The main mound covering ruins extends over 260 acres, and in the outskirts to the south, pottery and obsidian flakes and cores are scattered over some 700 acres.
Dr. Reichel, the American co-director of the project, said that excavations in the recent season turned up more evidence of “how the city looked the day it was destroyed.” In a swift and intense attack, he said, “buildings collapsed, burning out of control, burying everything in them under a vast pile of rubble.”
The excavators uncovered ruins of storerooms with many clay seals to secure baskets and other containers of commodities. They also investigated two large administrative buildings destroyed by fire. In the debris inside, they collected more than 1,000 round or oval-shaped clay bullets that would have been delivered by slings, then a principal weapon of warfare. One bullet had pierced the plaster of a mud-brick wall.
Twelve graves held the skeletons of likely battle victims.
The bullets and the pattern of destruction led the archaeologists to rule out earthquake damage and conclude that a tremendous battle had taken place. Dr. Reichel and other experts said there was no way to identify the aggressor, but they assumed it was the army of one of the southern cities.
When the archaeologists suggested in a 2005 report that a battle had been fought there, they encountered some skepticism from other researchers. But Dr. Algaze, who is not involved in the Hamoukar project, said the sling bullets, breached walls and widespread destruction “have convinced even the non-believers that this is evidence of conflict.”
The more recent discovery of the city’s production of sharp and durable tools from obsidian, a volcanic glass, may prove to be significant in understanding the economy of northern Mesopotamia in relation to the south, archaeologists say.
Well beyond the city center, the Hamoukar team found finished obsidian blades and the spoil of obsidian processing over hundreds of years, beginning around 4500 B.C. “They were not just using these tools here,” said Salam al-Kuntar, the project’s Syrian co-director. “They were making them here.”
The people at Hamoukar appeared to be taking raw obsidian, probably from deposits more than 100 miles away in Turkey, and turning it into a thriving export business. This and perhaps the later processing of copper, archaeologists say, might account for the city’s growth and apparent prosperity up to the time its walls came tumbling down in battle.
A penisula long thought to be part of Greenland's mainland turned out to be an island when a glacier retreated.
The Warming of Greenland
By JOHN COLLINS RUDOLF, The New York Times, January 16, 2007
LIVERPOOL LAND, Greenland — Flying over snow-capped peaks and into a thick fog, the helicopter set down on a barren strip of rocks between two glaciers. A dozen bags of supplies, a rifle and a can of cooking gas were tossed out onto the cold ground. Then, with engines whining, the helicopter lifted off, snow and fog swirling in the rotor wash.
When it had disappeared over the horizon, no sound remained but the howling of the Arctic wind.
“It feels a little like the days of the old explorers, doesn’t it?” Dennis Schmitt said.
Mr. Schmitt, a 60-year-old explorer from Berkeley, Calif., had just landed on a newly revealed island 400 miles north of the Arctic Circle in eastern Greenland. It was a moment of triumph: he had discovered the island on an ocean voyage in September 2005. Now, a year later, he and a small expedition team had returned to spend a week climbing peaks, crossing treacherous glaciers and documenting animal and plant life.
Despite its remote location, the island would almost certainly have been discovered, named and mapped almost a century ago when explorers like Jean-Baptiste Charcot and Philippe, Duke of Orléans, charted these coastlines. Would have been discovered had it not been bound to the coast by glacial ice.
Maps of the region show a mountainous peninsula covered with glaciers. The island’s distinct shape — like a hand with three bony fingers pointing north — looks like the end of the peninsula.
Now, where the maps showed only ice, a band of fast-flowing seawater ran between a newly exposed shoreline and the aquamarine-blue walls of a retreating ice shelf. The water was littered with dozens of icebergs, some as large as half an acre; every hour or so, several more tons of ice fractured off the shelf with a thunderous crack and an earth-shaking rumble.
All over Greenland and the Arctic, rising temperatures are not simply melting ice; they are changing the very geography of coastlines. Nunataks — “lonely mountains” in Inuit — that were encased in the margins of Greenland’s ice sheet are being freed of their age-old bonds, exposing a new chain of islands, and a new opportunity for Arctic explorers to write their names on the landscape.
“We are already in a new era of geography,” said the Arctic explorer Will Steger. “This phenomenon — of an island all of a sudden appearing out of nowhere and the ice melting around it — is a real common phenomenon now.”
In August, Mr. Steger discovered his own new island off the coast of the Norwegian island of Svalbard, high in the polar basin. Glaciers that had surrounded it when his ship passed through only two years earlier were gone this year, leaving only a small island alone in the open ocean.
“We saw it ourselves up there, just how fast the ice is going,” he said.
With 27,555 miles of coastline and thousands of fjords, inlets, bays and straits, Greenland has always been hard to map. Now its geography is becoming obsolete almost as soon as new maps are created.
Hans Jepsen is a cartographer at the Geological Survey of Denmark and Greenland, which produces topographical maps for mining and oil companies. (Greenland is a largely self-governing region of Denmark.) Last summer, he spotted several new islands in an area where a massive ice shelf had broken up. Mr. Jepsen was unaware of Mr. Schmitt’s discovery, and an old aerial photograph in his files showed the peninsula intact.
“Clearly, the new island was detached from the mainland when the connecting glacier-bridge retreated southward,” Mr. Jepsen said, adding that future maps would take note of the change.
The sudden appearance of the islands is a symptom of an ice sheet going into retreat, scientists say. Greenland is covered by 630,000 cubic miles of ice, enough water to raise global sea levels by 23 feet.
Carl Egede Boggild, a professor of snow-and-ice physics at the University Center of Svalbard, said Greenland could be losing more than 80 cubic miles of ice per year.
“That corresponds to three times the volume of all the glaciers in the Alps,” Dr. Boggild said. “If you lose that much volume you’d definitely see new islands appear.”
He discovered an island himself a year ago while flying over northwestern Greenland. “Suddenly I saw an island with glacial ice on it,” he said. “I looked at the map and it should have been a nunatak, but the present ice margin was about 10 kilometers away. So I can say that within the last five years the ice margin had retreated at least 10 kilometers.”
The abrupt acceleration of melting in Greenland has taken climate scientists by surprise. Tidewater glaciers, which discharge ice into the oceans as they break up in the process called calving, have doubled and tripled in speed all over Greenland. Ice shelves are breaking up, and summertime “glacial earthquakes” have been detected within the ice sheet.
“The general thinking until very recently was that ice sheets don’t react very quickly to climate,” said Martin Truffer, a glaciologist at the University of Alaska at Fairbanks. “But that thinking is changing right now, because we’re seeing things that people have thought are impossible.”
A study in The Journal of Climate last June observed that Greenland had become the single largest contributor to global sea-level rise.
Until recently, the consensus of climate scientists was that the impact of melting polar ice sheets would be negligible over the next 100 years. Ice sheets were thought to be extremely slow in reacting to atmospheric warming. The 2001 report by the Intergovernmental Panel on Climate Change, widely considered to be an authoritative scientific statement on the potential impacts of global warming, based its conclusions about sea-level rise on a computer model that predicted a slow onset of melting in Greenland.
“When you look at the ice sheet, the models didn’t work, which puts us on shaky ground,” said Richard Alley, a geosciences professor at Pennsylvania State University.
There is no consensus on how much Greenland’s ice will melt in the near future, Dr. Alley said, and no computer model that can accurately predict the future of the ice sheet. Yet given the acceleration of tidewater-glacier melting, a sea-level rise of a foot or two in the coming decades is entirely possible, he said. That bodes ill for island nations and those who live near the coast.
“Even a foot rise is a pretty horrible scenario,” said Stephen P. Leatherman, director of the Laboratory for Coastal Research at Florida International University in Miami.
On low-lying and gently sloping land like coastal river deltas, a sea-level rise of just one foot would send water thousands of feet inland. Hundreds of millions of people worldwide make their homes in such deltas; virtually all of coastal Bangladesh lies in the delta of the Ganges River. Over the long term, much larger sea-level rises would render the world’s coastlines unrecognizable, creating a whole new series of islands.
“Here in Miami,” Dr. Leatherman said, “we’re going to have an ocean on both sides of us.”
Such ominous implications are not lost on Mr. Schmitt, who says he hopes that the island he discovered in Greenland in September will become an international symbol of the effects of climate change. Mr. Schmitt, who speaks Inuit, has provisionally named it Uunartoq Qeqertoq: the warming island.
Global warming has profoundly altered the nature of polar exploration, said Mr. Schmitt, who in 40 years has logged more than 100 Arctic expeditions. Routes once pioneered on a dogsled are routinely paddled in a kayak now; many features, like the Ward Hunt Ice Shelf in Greenland’s northwest, have disappeared for good.
“There is a dark side to this,” he said about the new island. “We felt the exhilaration of discovery. We were exploring something new. But of course, there was also something scary about what we did there. We were looking in the face of these changes, and all of us were thinking of the dire consequences.”
By ANDREW POLLACK, The New York Times, January 16, 2007
The big news in the war on cervical cancer is the new vaccine recently approved to prevent the disease. But another major change that will affect millions of women is also under way, though more slowly and quietly.
The Pap smear, an annual ritual for many women and the mainstay of cervical cancer prevention for more than half a century, may start to fade in importance.
It will not disappear for many more years, if ever. But a newer genetic test that detects human papillomavirus, or HPV, which causes cervical cancer, is starting to play a bigger role in screening. And other genetic tests are being developed. At the least, some experts say, women will no longer need Pap smears as often.
“We can potentially change the entire cervical screening paradigm,” said Dr. Thomas C. Wright, a professor of pathology at Columbia University Medical Center who is also a consultant for Roche, which is developing a genetic HPV test.
The new vaccine could also deal a longer-term blow to Pap testing, which works by detecting abnormal cells from the cervix that could be on their way to becoming cancerous. It is not that women would no longer need screening because they had been vaccinated. The vaccine, approved only for girls and women 9 to 26 years old, does not protect against all strains of HPV that cause cancer.
If a precancerous lesion is present, the Pap test will detect it only 50 percent to 80 percent of the time. Pap testing is effective only because it is done often; a lesion can take 10 years to turn into a cancer, so a yearly test will probably find it in time.
As more women get the HPV vaccine, however, the number of lesions will decline, making the Pap test more costly per cancer case detected. And with fewer problems to detect, said Dr. Eduardo L. Franco, a professor of epidemiology and oncology at McGill University, the technicians who read Pap smears may lower their guard — and their accuracy.
Pap testing “is going to break down in a world in which vaccination decreases the prevalence of lesions,” said Dr. Franco, who said he had done some minor consulting for genetic test developers. Referring to the accuracy of Pap testing, he added, “It’s already bad enough, and it’s going to get worse.”
But Pap testing has its strong defenders, who question the value of the genetic test for HPV. Some gynecologists say having women come for annual Pap testing brings them in for other needed examinations. And there is a huge industry built up to provide the screening.
“The perception is that the annual Pap smear drives volume,” said Dr. Walter Kinney, a gynecological oncologist at Kaiser Permanente, the health maintenance organization. “I don’t see anyone raising their hand volunteering to give that up.”
At Kaiser, where doctors’ pay does not depend on customer volume, the genetic HPV test is offered with Pap testing to every woman 30 and older. If both tests are negative, a woman does not come back for further screening for three years. The savings from less frequent screening more than pay for the extra cost of the HPV test, Dr. Kinney said.
Kaiser’s testing laboratory in Berkeley, Calif., processes 300,000 to 500,000 cervical specimens a year. A robotic arm rapidly retrieves particular specimens from cold storage for testing and disposes of others when they are no longer needed.
The most recent guidelines from the American College of Obstetricians and Gynecologists, issued in 2003, suggested that some women over 30 do not need annual Pap tests, but many doctors and patients have resisted that idea.
“Sometimes you advocate that strategy, but the woman comes back the next year almost demanding the Pap smear,” said Dr. Juan Felix, a professor of pathology and of obstetrics and gynecology at the University of Southern California. “Women have been sort of mentally trained to come to get their annual test.”
Pap testing is named for Dr. George N. Papanicolaou, who developed the test at Cornell Medical School. It started to become widely used in the 1950s.
Cells are scraped from the surface of the cervix, spread on a microscope slide and examined for abnormalities that could indicate a precancerous lesion. If found and confirmed by further examination, the lesions can be removed by any of several techniques.
Pap testing has cut cervical cancer rates by 75 percent or more in nations with thorough screening. In the United States, there are now about 10,000 cases of cervical cancer each year and 4,000 deaths. More than half the cases are in women who do not undergo screening.
“It is one of the greatest public health interventions in terms of sheer success and lives saved,” said Philip E. Castle, an expert on cervical cancer screening at the National Cancer Institute.
But while successful, Dr. Castle said, Pap screening is “not very efficient,” costing billions of dollars a year. And it does miss cancer cases. A study of women with cervical cancer, conducted among members of seven health plans and published in The Journal of the National Cancer Institute in 2005, found that 32 percent had had one or more normal Pap tests in the three years before the diagnosis.
B. K. Cockrell, 57, a homemaker in Troup, Tex., was one woman who got cancer despite a series of normal Pap tests. In 2005, her gynecologist, Dr. A. Jay Staub of Dallas, also began giving the HPV genetic test, which gave a positive reading. Further examination showed that Ms. Cockrell had cancer, which was caught early enough to be removed by a hysterectomy without the need for chemotherapy or radiation.
“I believe I would be extremely ill today” if not for the HPV test, she said.
A newer form of Pap testing called liquid cytology, which spreads the cells more evenly on a slide, is said by some cytologists to be more sensitive, though some published studies contradict that.
But Pap testing has other problems as well. Of the 50 million to 60 million tests done in the United States each year, as many as two million are classified as ambiguous, possibly a lesion and possibly not. Such results require further testing, like colposcopy, an uncomfortable procedure in which the cervix is examined with a magnifying device, and biopsy, which can be painful.
The HPV genetic test looks for the DNA of 13 of the cancer-causing strains of the virus. Experts say this test can detect more than 90 percent of precancerous lesions. It is also easier to automate and far less likely to produce ambiguous results.
The samples are taken the same way as for a Pap test, meaning women still need to get into stirrups. But since the genetic test is less prone to error, experts say it is possible that in the future women will be able to take their own samples.
The test was first approved by the Food and Drug Administration in 1999, and its use has grown steadily, partly spurred by advertising by the test’s manufacturer, Digene. The company, based in Gaithersburg, Md., says about seven million Americans are getting the test each year, which is one-fifth of those it believes would be eligible. With Merck now calling attention to the role of HPV in its advertisements for its new vaccine, Digene executives expect interest in their test to grow.
Some experts say that since the HPV test catches more lesions than Pap, it would be cost-effective to make it the primary test, with Pap testing used only on the women who test positive for the virus.
“HPV testing as the stand-alone primary screening technology represents the scientifically obvious next step,” F. Xavier Bosch of the Catalán Institute of Oncology in Barcelona, Spain, wrote last August in a supplement of the journal Vaccine on the future of cervical cancer prevention.
But some experts say the HPV test is not ready for that.
One problem is that HPV testing costs $50 to more than $100, compared with as little as $20 for a Pap test. More significant, many, if not most, sexually active women will be infected with HPV at some point. But in most cases, particularly for younger women, the immune system dispenses with the virus.
That is why even those who advocate using HPV testing as the primary screen, or using it alongside Pap testing, do so only for women over 30 or 35, when the viral infection is less likely to be transient. (The HPV test is approved for two uses: to help resolve an ambiguous Pap test or to use in conjunction with Pap screening for women 30 and over.)
Dr. George Sawaya, an associate professor of obstetrics, gynecology and reproductive sciences at the University of California, San Francisco, says about 2,500 to 3,000 cervical cancer cases in the United States each year are in women with normal Pap tests. While use of the HPV test instead of the Pap as the primary screen may further reduce that number, “we have to make sure we are not dragging along tens of thousands of women who will have positive tests but no disease,” he said.
Some of those women would be subject to unnecessary biopsies and even to removal of lesions that would never turn cancerous, he said. The removal operations have risks of their own, he added, potentially raising the chances a woman will have premature deliveries in the future.
Wider use of HPV testing would also mean telling millions of women that they have a sexually transmitted disease, causing unnecessary stress. “Everybody presumes they are dirty when they are told they have something like this,” said Dr. Abbie Roth, an obstetrician and gynecologist at Northwestern Memorial Hospital in Chicago. “Everybody universally cries when they get that information.”
Digene says it hopes that European countries, which place more limits on medical spending than the United States, will make HPV testing the standard in place of the Pap. European experts disagree on whether that will happen.
But Pap testing is likely to be displaced in developing countries, which account for more than 80 percent of the roughly 500,000 new cases of cervical cancer and 275,000 deaths each year. Those countries cannot do efficient Pap screening for lack of laboratories and technicians and difficulty in getting women, who might have to walk miles to a clinic, to come for testing every year.
In the developing world, Pap testing has had “basically no impact on cervical cancer rates in any country, ever,” said Jacqueline Sherris, a strategic program leader for reproductive health at PATH, a nonprofit organization in Seattle.
PATH is working with Digene to develop a simpler and cheaper version of the HPV test for developing countries. Women might be tested only once or twice during their 30s but would get fairly good protection, Ms. Sherris said.
Still other tests are in development. One would determine the specific strain of HPV infecting a woman. Types 16 and 18 account for most cancers (and are the cancer-causing types targeted by the new vaccine). So having one of them would be considered more worrisome.
Yet another test would look for the activation of two genes, called E6 and E7. Such activation is believed to be required for a precancerous lesion to turn into cancer.
“Looking forward,” said Dr. Wright of Columbia, “the molecular tests are becoming so good that we can see a time when cytology is no longer used as the primary screening test.”
Huts have been reconstructed near the site as a heritage center.
Humble Brass Was Even Better Than Gold to a 16th-Century Tribe in Cuba
By JENNIFER PINKOWSKI, The New York Times, January 16, 2007
Because of its otherworldly brilliance, the 16th-century Taíno Indians of Cuba called it turey, their word for the most luminous part of the sky.
They adored its sweet smell, its reddish hue, its exotic origins and its dazzling iridescence, qualities that elevated it to the category of sacred materials known as guanín. Local chieftains wore it in pendants and medallions to show their wealth, influence and connection to the supernatural realm. Elite women and children were buried with it.
What was this treasured stuff? Humble brass — specifically, the lace tags and fasteners from Spanish explorers’ shoes and clothes, for which the Taíno eagerly traded their local gold.
A team of archaeologists from University College London and the Cuban Ministry of Science, Technology and Environment came to these conclusions by analyzing small brass tubes found in two dozen burial sites in the Taíno village of El Chorro de Maíta in northeastern Cuba, according to a recent paper in The Journal of Archaeological Science.
The graves mostly date to the late 15th and early 16th centuries, when waves of gold-hungry conquistadors landed on Caribbean shores. Within decades, the Taíno, like their neighbors the Carib and the Arawak, were largely wiped out by genocide, slavery and disease.
But the archaeologists say this is not the whole picture. Their research — the first systematic study of metals from a Cuban archaeological site — focuses on one of the few indigenous settlements ever found that date from the period after the arrival of Europeans. The scientists say the finds add important detail and nuance to a history of the Caribbean long dominated by the first-person reportage of the Europeans themselves.
“It’s certainly true that the arrival of the Europeans was in the short term devastating,” said Marcos Martinón-Torres of University College London, the project’s lead researcher. “But instead of lumping the Taíno in all together as ‘the Indians of Cuba who were eliminated by the Spaniards,’ we’re trying to show they were people who made choices. They had their own lives. They decided to incorporate European goods into their value system.”
Brass first came to the Americas with Europeans. While a few brass artifacts have been found elsewhere in the Caribbean, no one knows when and how they were acquired. In contrast, El Chorro, first excavated in the mid-1980s, is one of the best-preserved sites in Cuba, and its artifacts have a clear archaeological context.
Training X-rays and microscopes on a half-dozen pendants, Dr. Martinón-Torres and a Cuban archaeologist, Roberto Valcárcel Rojas, determined the metals’ bulk chemical composition. It was a mixture of zinc and copper — the elements of brass.
They then used a scanning electron microscope to find the pendants’ unique geochemical signature. All came from Nuremberg, Germany, a center of brass production since the Middle Ages.
The few other metal artifacts from the cemetery — pendants made from a gold-copper-silver alloy — probably came from Colombia, where the Taíno are thought to have originated. Only two tiny gold nuggets, of local origin, were found.
Sixteenth-century portraits in places like the Tate Gallery held further clues. Many subjects wear bootlaces and bodices fastened with objects strikingly like those found in the graves. Similar objects have been excavated from early colonial settlements, including Havana and Jamestown, Va.
European accounts said the Taíno traded 200 pieces of gold for a single piece of guanín, of which brass was the highest form. Yet the residents of El Chorro may not have considered the trade unfair, said Jago Cooper, a field director for the project. In fact, access to European brass may have increased the power of local chieftains, hastening the transition from an egalitarian society to a hierarchical one.
The finds from El Chorro suggest that interaction between the Taíno and the Europeans may have been more varied than once thought.
“Large European materials being incorporated into their culture, and exotic materials being used to reflect Taíno beliefs — it’s new, important evidence for what was happening during contact,” said William F. Keegan, an archaeologist at the University of Florida and the co-editor of The Journal of Caribbean Archaeology, who was not involved in the research. “There’s been a tendency to assume the Taínos quickly disappeared due to European diseases and harsh treatment by the Spanish, but there’s increasing evidence that the culture continued to be vibrant until the middle of the 16th century.”
Some of that evidence comes from another site in Cuba: Los Buchillones, a coastal settlement about 200 miles west of El Chorro de Maíta. First excavated in 1998 by a Cuban-Canadian team, Los Buchillones is the site of the only known intact Taíno house. In the last decade, continuing study of the site and the surrounding region by Mr. Valcárcel Rojas and Mr. Cooper has revealed a community with trade networks all over the Greater Antilles that survived into the Spanish colonial period in the early 17th century. Clearly, they would have known about Europeans’ presence, but chose to avoid contact, unlike El Chorro’s chieftains. It may have kept them alive longer.
Together, the sites hint at an array of tactics not documented by the Europeans. “Most accounts seem to be based on the idea that Europeans ‘acted’ and Taíno ‘reacted,’ ” said Elizabeth Graham of University College London, who with her husband, David Pendergast, first excavated Los Buchillones. “In the case of El Chorro de Maíta, the Taíno were clearly being proactive.”
The finds at El Chorro also help to fill a hole in the study of the Caribbean past created by Cuba’s political isolation. Archaeology of the island has been little known outside of its borders since the 1959 revolution. Very few foreign archaeologists have dug there, and the few field reports published by Cuban archaeologists, mostly trained by Soviet scholars, are difficult to get outside the country.
In recent years, there have been efforts to bring Cuban archaeology out of the long shadow cast by the 45-year-old United States sanctions. In 2005, the scholarly volume Dialogues in Cuban Archaeology assembled a dozen English-language reports in one place. (In it is a paper Mr. Valcárcel Rojas co-wrote about El Chorro de Maíta.) The relatively new Journal of Caribbean Archaeology currently has its first Cuban paper in peer review.
For most American archaeologists, papers published by their international colleagues are about as close as they are going to get to Cuba these days. Since 2004, the Bush administration has greatly tightened restrictions on educational travel to Cuba; programs under 10 weeks are now prohibited. Last summer, Florida went a step further, banning public universities from spending money on research in countries the State Department considers state sponsors of terrorism, including Cuba. Both sets of regulations are being challenged in court.
Last spring, Mr. Valcárcel Rojas was denied a visa to attend the annual Society for American Archaeology conference in Puerto Rico. Dr. Martinón-Torres and Mr. Cooper presented the research — which received Cuba’s highest academic prize — without him.
Still, the British-Cuban team is seeking a three-year grant in hopes of uncovering the trade and social networks that connected El Chorro’s inhabitants — in particular, the effects of the brass-gold trade on those connections. And there is European behavior to puzzle out, too.
“We would expect the Europeans to load up with brass in their cargos, but we haven’t found that brass in Cuba,” Dr. Martinón-Torres said. “It’s possible it hasn’t been recognized by archaeologists. We expect if both sides were happy with this exchange, there must be more evidence of it.”
Archaeological digs at Tell Hamoukar in Syria have yielded the remains of a body, possibly a war casualty.
Ruins in Northern Syria Bear the Scars of a City’s Final Battle
By JOHN NOBLE WILFORD, The New York Times, January 16, 2007
Archaeologists digging in Syria, in the upper reaches of what was ancient Mesopotamia, have found new evidence of how one of the world’s earliest cities met a violent end by fire, collapsing walls and roofs, and a fierce rain of clay bullets. The battle left some of the oldest known ruins of organized warfare.
The excavations at the city, Tell Hamoukar, which was destroyed in about 3500 B.C., have also exposed remains suggesting its origins as a manufacturing center for obsidian tools and blades, perhaps as early as 4500 B.C.
The two discoveries were made in September and October and announced yesterday by the Oriental Institute of the University of Chicago and the Syrian Department of Antiquities. The site is in northeastern Syria, less than five miles from the Iraqi border.
The proximity to Iraq is not insignificant. Driven out of Iraq by the war and political turmoil, Western archaeologists who specialize in the first urban civilization that flourished in Mesopotamia have had to shift their digging to the northern fringes of the Tigris and Euphrates river valleys, in Syria and Turkey.
As a result, archaeologists are gaining a broader perspective on a transformative period in antiquity that saw the rise of the first cities, specialization in work, stratification of society and eventually, the first known writing. While the more thoroughly studied urban centers in southern Iraq may have been earlier and more powerful city-states that coalesced into empires, those in the north were not as peripheral as once assumed. Some of them developed robust cultures more or less independent of the south. Trade between the two regions was common, and so apparently was conflict.
“We are learning that what was happening in the north cannot be explained as just simple expansion of southern culture,” said Clemens Reichel, a University of Chicago archaeologist who is excavating the battle ruins at the site. Guillermo Algaze, an archaeologist at the University of California, San Diego, who specializes in north-south relations in ancient Mesopotamia, said, “our interpretations are going to shift,” when these new findings are published.
Expanded excavations at Tell Brak, Habuba Kabira, Hamoukar and elsewhere in northern Syria, Dr. Algaze said, have revealed that some northern cities were larger at an earlier time than was expected. And ample evidence is being found for specialized industries like the obsidian works at Hamoukar.
“We are formulating questions to ask when we get back in southern Iraq,” Dr. Algaze said.
Almost no field work has been done in Iraq since 1990, leaders of Mesopotamian archaeology say, and concern is mounting that war and looting have left prized sites in disarray. New hydroelectric projects are another spur to stepped-up excavations in Syria and Turkey. Archaeologists are rushing to dig before ruins are inundated by dammed rivers.
Research at Hamoukar has been under way since 1999. The Chicago-Syria team has now determined that the 40-acre heart of the city was surrounded by a 10-foot-thick wall. The main mound covering ruins extends over 260 acres, and in the outskirts to the south, pottery and obsidian flakes and cores are scattered over some 700 acres.
Dr. Reichel, the American co-director of the project, said that excavations in the recent season turned up more evidence of “how the city looked the day it was destroyed.” In a swift and intense attack, he said, “buildings collapsed, burning out of control, burying everything in them under a vast pile of rubble.”
The excavators uncovered ruins of storerooms with many clay seals to secure baskets and other containers of commodities. They also investigated two large administrative buildings destroyed by fire. In the debris inside, they collected more than 1,000 round or oval-shaped clay bullets that would have been delivered by slings, then a principal weapon of warfare. One bullet had pierced the plaster of a mud-brick wall.
Twelve graves held the skeletons of likely battle victims.
The bullets and the pattern of destruction led the archaeologists to rule out earthquake damage and conclude that a tremendous battle had taken place. Dr. Reichel and other experts said there was no way to identify the aggressor, but they assumed it was the army of one of the southern cities.
When the archaeologists suggested in a 2005 report that a battle had been fought there, they encountered some skepticism from other researchers. But Dr. Algaze, who is not involved in the Hamoukar project, said the sling bullets, breached walls and widespread destruction “have convinced even the non-believers that this is evidence of conflict.”
The more recent discovery of the city’s production of sharp and durable tools from obsidian, a volcanic glass, may prove to be significant in understanding the economy of northern Mesopotamia in relation to the south, archaeologists say.
Well beyond the city center, the Hamoukar team found finished obsidian blades and the spoil of obsidian processing over hundreds of years, beginning around 4500 B.C. “They were not just using these tools here,” said Salam al-Kuntar, the project’s Syrian co-director. “They were making them here.”
The people at Hamoukar appeared to be taking raw obsidian, probably from deposits more than 100 miles away in Turkey, and turning it into a thriving export business. This and perhaps the later processing of copper, archaeologists say, might account for the city’s growth and apparent prosperity up to the time its walls came tumbling down in battle.
A penisula long thought to be part of Greenland's mainland turned out to be an island when a glacier retreated.
The Warming of Greenland
By JOHN COLLINS RUDOLF, The New York Times, January 16, 2007
LIVERPOOL LAND, Greenland — Flying over snow-capped peaks and into a thick fog, the helicopter set down on a barren strip of rocks between two glaciers. A dozen bags of supplies, a rifle and a can of cooking gas were tossed out onto the cold ground. Then, with engines whining, the helicopter lifted off, snow and fog swirling in the rotor wash.
When it had disappeared over the horizon, no sound remained but the howling of the Arctic wind.
“It feels a little like the days of the old explorers, doesn’t it?” Dennis Schmitt said.
Mr. Schmitt, a 60-year-old explorer from Berkeley, Calif., had just landed on a newly revealed island 400 miles north of the Arctic Circle in eastern Greenland. It was a moment of triumph: he had discovered the island on an ocean voyage in September 2005. Now, a year later, he and a small expedition team had returned to spend a week climbing peaks, crossing treacherous glaciers and documenting animal and plant life.
Despite its remote location, the island would almost certainly have been discovered, named and mapped almost a century ago when explorers like Jean-Baptiste Charcot and Philippe, Duke of Orléans, charted these coastlines. Would have been discovered had it not been bound to the coast by glacial ice.
Maps of the region show a mountainous peninsula covered with glaciers. The island’s distinct shape — like a hand with three bony fingers pointing north — looks like the end of the peninsula.
Now, where the maps showed only ice, a band of fast-flowing seawater ran between a newly exposed shoreline and the aquamarine-blue walls of a retreating ice shelf. The water was littered with dozens of icebergs, some as large as half an acre; every hour or so, several more tons of ice fractured off the shelf with a thunderous crack and an earth-shaking rumble.
All over Greenland and the Arctic, rising temperatures are not simply melting ice; they are changing the very geography of coastlines. Nunataks — “lonely mountains” in Inuit — that were encased in the margins of Greenland’s ice sheet are being freed of their age-old bonds, exposing a new chain of islands, and a new opportunity for Arctic explorers to write their names on the landscape.
“We are already in a new era of geography,” said the Arctic explorer Will Steger. “This phenomenon — of an island all of a sudden appearing out of nowhere and the ice melting around it — is a real common phenomenon now.”
In August, Mr. Steger discovered his own new island off the coast of the Norwegian island of Svalbard, high in the polar basin. Glaciers that had surrounded it when his ship passed through only two years earlier were gone this year, leaving only a small island alone in the open ocean.
“We saw it ourselves up there, just how fast the ice is going,” he said.
With 27,555 miles of coastline and thousands of fjords, inlets, bays and straits, Greenland has always been hard to map. Now its geography is becoming obsolete almost as soon as new maps are created.
Hans Jepsen is a cartographer at the Geological Survey of Denmark and Greenland, which produces topographical maps for mining and oil companies. (Greenland is a largely self-governing region of Denmark.) Last summer, he spotted several new islands in an area where a massive ice shelf had broken up. Mr. Jepsen was unaware of Mr. Schmitt’s discovery, and an old aerial photograph in his files showed the peninsula intact.
“Clearly, the new island was detached from the mainland when the connecting glacier-bridge retreated southward,” Mr. Jepsen said, adding that future maps would take note of the change.
The sudden appearance of the islands is a symptom of an ice sheet going into retreat, scientists say. Greenland is covered by 630,000 cubic miles of ice, enough water to raise global sea levels by 23 feet.
Carl Egede Boggild, a professor of snow-and-ice physics at the University Center of Svalbard, said Greenland could be losing more than 80 cubic miles of ice per year.
“That corresponds to three times the volume of all the glaciers in the Alps,” Dr. Boggild said. “If you lose that much volume you’d definitely see new islands appear.”
He discovered an island himself a year ago while flying over northwestern Greenland. “Suddenly I saw an island with glacial ice on it,” he said. “I looked at the map and it should have been a nunatak, but the present ice margin was about 10 kilometers away. So I can say that within the last five years the ice margin had retreated at least 10 kilometers.”
The abrupt acceleration of melting in Greenland has taken climate scientists by surprise. Tidewater glaciers, which discharge ice into the oceans as they break up in the process called calving, have doubled and tripled in speed all over Greenland. Ice shelves are breaking up, and summertime “glacial earthquakes” have been detected within the ice sheet.
“The general thinking until very recently was that ice sheets don’t react very quickly to climate,” said Martin Truffer, a glaciologist at the University of Alaska at Fairbanks. “But that thinking is changing right now, because we’re seeing things that people have thought are impossible.”
A study in The Journal of Climate last June observed that Greenland had become the single largest contributor to global sea-level rise.
Until recently, the consensus of climate scientists was that the impact of melting polar ice sheets would be negligible over the next 100 years. Ice sheets were thought to be extremely slow in reacting to atmospheric warming. The 2001 report by the Intergovernmental Panel on Climate Change, widely considered to be an authoritative scientific statement on the potential impacts of global warming, based its conclusions about sea-level rise on a computer model that predicted a slow onset of melting in Greenland.
“When you look at the ice sheet, the models didn’t work, which puts us on shaky ground,” said Richard Alley, a geosciences professor at Pennsylvania State University.
There is no consensus on how much Greenland’s ice will melt in the near future, Dr. Alley said, and no computer model that can accurately predict the future of the ice sheet. Yet given the acceleration of tidewater-glacier melting, a sea-level rise of a foot or two in the coming decades is entirely possible, he said. That bodes ill for island nations and those who live near the coast.
“Even a foot rise is a pretty horrible scenario,” said Stephen P. Leatherman, director of the Laboratory for Coastal Research at Florida International University in Miami.
On low-lying and gently sloping land like coastal river deltas, a sea-level rise of just one foot would send water thousands of feet inland. Hundreds of millions of people worldwide make their homes in such deltas; virtually all of coastal Bangladesh lies in the delta of the Ganges River. Over the long term, much larger sea-level rises would render the world’s coastlines unrecognizable, creating a whole new series of islands.
“Here in Miami,” Dr. Leatherman said, “we’re going to have an ocean on both sides of us.”
Such ominous implications are not lost on Mr. Schmitt, who says he hopes that the island he discovered in Greenland in September will become an international symbol of the effects of climate change. Mr. Schmitt, who speaks Inuit, has provisionally named it Uunartoq Qeqertoq: the warming island.
Global warming has profoundly altered the nature of polar exploration, said Mr. Schmitt, who in 40 years has logged more than 100 Arctic expeditions. Routes once pioneered on a dogsled are routinely paddled in a kayak now; many features, like the Ward Hunt Ice Shelf in Greenland’s northwest, have disappeared for good.
“There is a dark side to this,” he said about the new island. “We felt the exhilaration of discovery. We were exploring something new. But of course, there was also something scary about what we did there. We were looking in the face of these changes, and all of us were thinking of the dire consequences.”
