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Basics: The Ambivalent Bond With a Ball of Fur
By NATALIE ANGIER, The New York Times, October 2, 2007
A couple of weeks ago, while I was out of town on business, our cat, Cleo, died of liver failure. My husband and daughter buried her in the backyard, not far from the grave of our other cat, Manny, who had died just a few months earlier of mouth cancer.
Cleo was almost 16 years old, she’d been sick, and her death was no surprise. Still, when I returned to a home without cats, without pets of any sort, I was startled by my grief — not so much its intensity as its specificity.
It was very different from the catastrophic grief I’d felt when I was 19 and my father died, and all sense, color and flooring dropped from my days. This was a sorrow of details, of minor rhythms and assumptions that I hadn’t really been aware of until, suddenly, they were disrupted or unmet. Hey, I’m opening the door to the unfinished attic now. Doesn’t a cat want to try dashing inside to roll around in the loose wads of insulation while I yell at it to get out of there?
I’ve just dumped a pile of clean laundry on the bed and I’m starting to fold it. Why aren’t the cats jumping up for a quick sit? Don’t they know everything is still warm?
We expect the bonds between children and parents, or between lovers or close friends, to be fierce and complex, and that makes them easy to understand. We expect the bonds between people and their pets to be simple and innocent, an antidote to human judgment and the fog of human speech, and that can make the bond paradoxically harder to track or explain. How do we feel about the nonhuman animals whose company we crave? We think we know. Our pet is our “best friend,” a “member of the family,” a surrogate child for the adults, in loco parentis for the kids and the best possible pillow for whoever has first dibs.
Pets are growing ever more popular. In 1988, according to the American Pet Products Manufacturers Association, 56 percent of American households had a pet. By 2006, that figure had climbed to 63 percent, which works out to a national census of 88 million owned cats, 75 million dogs, 16 million birds, 14 million horses, 142 million fish, assorted small mammals and the occasional leopard or Madagascan hissing cockroach.
We love our pets and we love the idea of pets, of reaching beyond the parochial barriers of the human race to commune with other species. When Alex the African gray parrot, renowned for his ability to communicate, do simple arithmetic and describe objects by their color, size, shape and material, died last month of cardiovascular disease at the age of 31, his obituary appeared everywhere, and Irene Pepperberg, the scientist who had trained Alex since 1977, was flooded with condolences.
“Alex touched so many people,” Dr. Pepperberg, a lecturer and research associate at Harvard University, said in a telephone interview. “He broke all preconceived notions of what it means to be a bird brain.” She admitted to feeling devastated. “There’s a parrot-size hole in my life,” she said.
Yet part of the reason Alex’s death attracted so much sympathy, and why Dr. Pepperberg’s grief seems normal rather than excessive, is that Alex, in the public eye, was neither pet nor ordinary parrot. He was Pinocchio, striving to realize his full potential — his humanity. Importantly, Alex didn’t merely nuzzle his affection for Dr. Pepperberg. He had genuine dying words, the fine four-hanky phrase, “I love you.”
By contrast, when Leona Helmsley, the hotel magnate who died in August, specified in her will that she was leaving $12 million to her pet dog, Trouble, while stiffing two of her grandchildren, there was scant talk of dogs as best friends. There were hoots, clucks and growls, with one reader on The New York Times Web site advising the grandchildren to “go kill that stupid dog.”
Marc Hauser, professor of psychology at Harvard and author of “Wild Minds: What Animals Really Think,” says ambivalence and tension have long been woven into our feelings about animals. “On the one hand, we feel a connection to other animals and we can’t imagine a world where we’re the only species on the planet,” he said. “On the other hand, we’re always trying to show that we’re not animals. We’re like them, yet we don’t want to be like them.”
Dr. Hauser traces this tension to self-defense. We use animals, and we want to feel justified in using animals. We eat their muscles for meat, flay their hides for shoes and accessories, inject them with experimental vaccines, genetically engineer them into grotesque morphologies to study human diseases. This requires a certain mental distance.
So we adore our pets and lavish time and money on them. Annual pet expenditures in this country have doubled in the last decade and are now more than $40 billion a year. And then we scold ourselves for our foolish fiscal priorities.
We adore our pets and can come to identify with them so deeply that we attribute to them some truly daffy notions, like the radio listener who called in a comment to Colin Allen, a philosopher and cognitive scientist at Indiana University’s Center for the Integrative Study of Animal Behavior. “She wanted to tell me about how her cat had very gingerly brought in an injured bird to show her, as though to say, It’s hurt, please take care of it,” Dr. Allen said. “I suggested there might be other interpretations for her cat’s behavior.”
Yes, we love our pets and anthropomorphize them to the point where we think our cat might enjoy wearing the mouse hat Halloween costume now on sale at Petsmart.com. And still we abandon difficult pets, and shelters euthanize some 10 million pets a year.
I understand the ambivalence of the human-animal bond. I loved my cats, and I miss them, but I resent them, too, for showing me what a creature of small habits I am, and for reminding me that even love is not enough. Life, like the laundry, will always cool down.
Fossil DNA Expands Neanderthal Range
By NICHOLAS WADE, The New York Times, October 2, 2007
In the Treaty of Tordesillas, Spain and Portugal divided the world outside Europe between them. That was not the first time that two rival groups carved up the globe. More than 50,000 years ago, all the world outside Africa was divided between two archaic human species.
The Neanderthals held sway in Europe and the Near East, bottling up the troublesome ancestors of modern humans in Africa, and Homo erectus dominated East Asia. But a new discovery suggests that this division of the world may not have been quite so clear-cut.
Neanderthals evolved their distinctive features some 400,000 years ago, but these are often hard to detect in fragmentary pieces of bone. Another way of identifying Neanderthals has been developed by Svante Paabo at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.
Even though all fossil bones in museums are heavily contaminated with human DNA, Dr. Paabo has shown that Neanderthal DNA can be picked out and identified. So far, he and others have identified DNA from 13 European Neanderthals.
He and colleagues have now identified Neanderthal mitochondrial DNA in bones at two new sites, they say in an article published electronically in Nature this week. One is Teshik Tash, in Uzbekistan, some 750 miles east of the Caspian Sea and, until now, the easternmost known limit of Neanderthal territory. The other bones are from the Okladnikov cave in the Altai mountains, some 1,250 miles farther east.
This huge extension of the Neanderthal’s known range puts them well into southern Siberia.
Because the mitochondrial DNA sequence of the new finds differs only slightly from that of the European Neanderthals, Dr. Paabo believes that they may have moved into Siberia relatively late in the Neanderthal period, perhaps as recently as 127,000 years ago, when a warm period made Siberia more accessible.
If Neanderthals penetrated as far as Siberia, might they have reached ever farther east, trespassing far into the assumed domain of Homo erectus? “We now know that they are on the doorstep to Mongolia and even China, so I would not be surprised if we one day find a Marco Polo Neanderthal,” Dr. Paabo said in an e-mail message. “Conceivably, they may even have contributed to the extinction of H. erectus forms in Asia.”
But Richard Klein, a paleoanthropologist at Stanford University, said the many archaic human fossils of this period from China “bear no resemblance to the Neanderthals.” Any DNA from these fossil bones would be interesting, Dr. Klein said, but “I’d be amazed if it was Neanderthal-like.”
Arctic Melt Unnerves the Experts
By ANDREW C. REVKIN, The New York Times, October 2, 2007
The Arctic ice cap shrank so much this summer that waves briefly lapped along two long-imagined Arctic shipping routes, the Northwest Passage over Canada and the Northern Sea Route over Russia.
Over all, the floating ice dwindled to an extent unparalleled in a century or more, by several estimates.
Now the six-month dark season has returned to the North Pole. In the deepening chill, new ice is already spreading over vast stretches of the Arctic Ocean. Astonished by the summer’s changes, scientists are studying the forces that exposed one million square miles of open water — six Californias — beyond the average since satellites started measurements in 1979.
At a recent gathering of sea-ice experts at the University of Alaska in Fairbanks, Hajo Eicken, a geophysicist, summarized it this way: “Our stock in trade seems to be going away.”
Scientists are also unnerved by the summer’s implications for the future, and their ability to predict it.
Complicating the picture, the striking Arctic change was as much a result of ice moving as melting, many say. A new study, led by Son Nghiem at NASA’s Jet Propulsion Laboratory and appearing this week in Geophysical Research Letters, used satellites and buoys to show that winds since 2000 had pushed huge amounts of thick old ice out of the Arctic basin past Greenland. The thin floes that formed on the resulting open water melted quicker or could be shuffled together by winds and similarly expelled, the authors said.
The pace of change has far exceeded what had been estimated by almost all the simulations used to envision how the Arctic will respond to rising concentrations of greenhouse gases linked to global warming. But that disconnect can cut two ways. Are the models overly conservative? Or are they missing natural influences that can cause wide swings in ice and temperature, thereby dwarfing the slow background warming?
The world is paying more attention than ever.
Russia, Canada and Denmark, prompted in part by years of warming and the ice retreat this year, ratcheted up rhetoric and actions aimed at securing sea routes and seabed resources.
Proponents of cuts in greenhouse gases cited the meltdown as proof that human activities are propelling a slide toward climate calamity.
Arctic experts say things are not that simple. More than a dozen experts said in interviews that the extreme summer ice retreat had revealed at least as much about what remains unknown in the Arctic as what is clear. Still, many of those scientists said they were becoming convinced that the system is heading toward a new, more watery state, and that human-caused global warming is playing a significant role.
For one thing, experts are having trouble finding any records from Russia, Alaska or elsewhere pointing to such a widespread Arctic ice retreat in recent times, adding credence to the idea that humans may have tipped the balance. Many scientists say the last substantial warming in the region, peaking in the 1930s, mainly affected areas near Greenland and Scandinavia.
Some scientists who have long doubted that a human influence could be clearly discerned in the Arctic’s changing climate now agree that the trend is hard to ascribe to anything else.
“We used to argue that a lot of the variability up to the late 1990s was induced by changes in the winds, natural changes not obviously related to global warming,” said John Michael Wallace, a scientist at the University of Washington. “But changes in the last few years make you have to question that. I’m much more open to the idea that we might have passed a point where it’s becoming essentially irreversible.”
Experts say the ice retreat is likely to be even bigger next summer because this winter’s freeze is starting from such a huge ice deficit. At least one researcher, Wieslaw Maslowski of the Naval Postgraduate School in Monterey, Calif., projects a blue Arctic Ocean in summers by 2013.
In essence, Arctic waters may be behaving more like those around Antarctica, where a broad fringe of sea ice builds each austral winter and nearly disappears in the summer. (Reflecting the different geography and dynamics at the two poles, there has been a slight increase in sea-ice area around Antarctica in recent decades.)
While open Arctic waters could be a boon for shipping, fishing and oil exploration, an annual seesawing between ice and no ice could be a particularly harsh jolt to polar bears.
Many Arctic researchers warned that it was still far too soon to start sending container ships over the top of the world. “Natural variations could turn around and counteract the greenhouse-gas-forced change, perhaps stabilizing the ice for a bit,” said Marika Holland, of the National Center for Atmospheric Research in Boulder, Colo.
But, she added, that will not last. “Eventually the natural variations would again reinforce the human-driven change, perhaps leading to even more rapid retreat,” Dr. Holland said. “So I wouldn’t sign any shipping contracts for the next 5 to 10 years, but maybe the next 20 to 30.”
While experts debate details, many agree that the vanishing act of the sea ice this year was probably caused by superimposed forces including heat-trapping clouds and water vapor in the air, as well as the ocean-heating influence of unusually sunny skies in June and July. Other important factors were warm winds flowing from Siberia around a high-pressure system parked over the ocean. The winds not only would have melted thin ice but also pushed floes offshore where currents and winds could push them out of the Arctic Ocean.
But another factor was probably involved, one with roots going back to about 1989. At that time, a periodic flip in winds and pressure patterns over the Arctic Ocean, called the Arctic Oscillation, settled into a phase that tended to stop ice from drifting in a gyre for years, so it could thicken, and instead carried it out to the North Atlantic.
The new NASA study of expelled old ice builds on previous measurements showing that the proportion of thick, durable floes that were at least 10 years old dropped to 2 percent this spring from 80 percent in the spring of 1987, said Ignatius G. Rigor, an ice expert at the University of Washington and an author of the new NASA-led study.
Without the thick ice, which can endure months of nonstop summer sunshine, more dark open water and thin ice absorbed solar energy, adding to melting and delaying the winter freeze.
The thinner fresh-formed ice was also more vulnerable to melting from heat held near the ocean surface by clouds and water vapor. This may be where the rising influence of humans on the global climate system could be exerting the biggest regional influence, said Jennifer A. Francis of Rutgers University.
Other Arctic experts, including Dr. Maslowski in Monterey and Igor V. Polyakov at the University of Alaska, Fairbanks, also see a role in rising flows of warm water entering the Arctic Ocean through the Bering Strait between Alaska and Russia, and in deep currents running north from the Atlantic Ocean near Scandinavia.
A host of Arctic scientists say it is too soon to know if the global greenhouse effect has already tipped the system to a condition in which sea ice in summers will be routinely limited to a few clotted passageways in northern Canada.
But at the university in Fairbanks — where signs of northern warming include sinkholes from thawing permafrost around its Arctic research center — Dr. Eicken and other experts are having a hard time conceiving a situation that could reverse the trends.
“The Arctic may have another ace up her sleeve to help the ice grow back,” Dr. Eicken said. “But from all we can tell right now, the means for that are quite limited.”
Observatory: In a Primitive Tool, Evidence of Trading in the Pacific
By HENRY FOUNTAIN, The New York Times, October 2, 2007
East Polynesia, those remote eastern Pacific islands like Tahiti, the Marquesas and the Tuamotus, was the last part of the planet to be settled, reached by peoples from the western Pacific who voyaged over broad stretches of ocean in canoes, starting about 4,000 years ago.
There has always been a question of how expert these ocean travelers were — whether the voyages were lucky accidents or purposeful expeditions. Most anthropologists think these voyagers knew what they were doing, but no one knows for certain, nor whether there was extensive cross-ocean trading among the islands once they were settled.
But Kenneth D. Collerson and Marshall I. Weisler of the University of Queensland in Australia provide some clues, through a study of old stone adzes found on the Tuamotus.
The adzes have basalt blades. Since they were found on coral atolls, the basalt had to come from volcanic islands elsewhere. By determining concentrations of trace elements and certain isotopes in each blade, the researchers were able to determine where they came from. The study was published in Science.
Most of the blades were found to have come from four island groups, suggesting there was extensive trading across more than 1,000 miles of ocean. And one of the blades was from much farther away — Hawaii, 2,400 miles to the northwest. Hawaiian oral histories include mentions of long voyages to Tahiti by way of the Tuamotus, so this finding supports those histories — and the idea that the early Polynesian settlers were skillful navigators as well.
By NATALIE ANGIER, The New York Times, October 2, 2007
A couple of weeks ago, while I was out of town on business, our cat, Cleo, died of liver failure. My husband and daughter buried her in the backyard, not far from the grave of our other cat, Manny, who had died just a few months earlier of mouth cancer.
Cleo was almost 16 years old, she’d been sick, and her death was no surprise. Still, when I returned to a home without cats, without pets of any sort, I was startled by my grief — not so much its intensity as its specificity.
It was very different from the catastrophic grief I’d felt when I was 19 and my father died, and all sense, color and flooring dropped from my days. This was a sorrow of details, of minor rhythms and assumptions that I hadn’t really been aware of until, suddenly, they were disrupted or unmet. Hey, I’m opening the door to the unfinished attic now. Doesn’t a cat want to try dashing inside to roll around in the loose wads of insulation while I yell at it to get out of there?
I’ve just dumped a pile of clean laundry on the bed and I’m starting to fold it. Why aren’t the cats jumping up for a quick sit? Don’t they know everything is still warm?
We expect the bonds between children and parents, or between lovers or close friends, to be fierce and complex, and that makes them easy to understand. We expect the bonds between people and their pets to be simple and innocent, an antidote to human judgment and the fog of human speech, and that can make the bond paradoxically harder to track or explain. How do we feel about the nonhuman animals whose company we crave? We think we know. Our pet is our “best friend,” a “member of the family,” a surrogate child for the adults, in loco parentis for the kids and the best possible pillow for whoever has first dibs.
Pets are growing ever more popular. In 1988, according to the American Pet Products Manufacturers Association, 56 percent of American households had a pet. By 2006, that figure had climbed to 63 percent, which works out to a national census of 88 million owned cats, 75 million dogs, 16 million birds, 14 million horses, 142 million fish, assorted small mammals and the occasional leopard or Madagascan hissing cockroach.
We love our pets and we love the idea of pets, of reaching beyond the parochial barriers of the human race to commune with other species. When Alex the African gray parrot, renowned for his ability to communicate, do simple arithmetic and describe objects by their color, size, shape and material, died last month of cardiovascular disease at the age of 31, his obituary appeared everywhere, and Irene Pepperberg, the scientist who had trained Alex since 1977, was flooded with condolences.
“Alex touched so many people,” Dr. Pepperberg, a lecturer and research associate at Harvard University, said in a telephone interview. “He broke all preconceived notions of what it means to be a bird brain.” She admitted to feeling devastated. “There’s a parrot-size hole in my life,” she said.
Yet part of the reason Alex’s death attracted so much sympathy, and why Dr. Pepperberg’s grief seems normal rather than excessive, is that Alex, in the public eye, was neither pet nor ordinary parrot. He was Pinocchio, striving to realize his full potential — his humanity. Importantly, Alex didn’t merely nuzzle his affection for Dr. Pepperberg. He had genuine dying words, the fine four-hanky phrase, “I love you.”
By contrast, when Leona Helmsley, the hotel magnate who died in August, specified in her will that she was leaving $12 million to her pet dog, Trouble, while stiffing two of her grandchildren, there was scant talk of dogs as best friends. There were hoots, clucks and growls, with one reader on The New York Times Web site advising the grandchildren to “go kill that stupid dog.”
Marc Hauser, professor of psychology at Harvard and author of “Wild Minds: What Animals Really Think,” says ambivalence and tension have long been woven into our feelings about animals. “On the one hand, we feel a connection to other animals and we can’t imagine a world where we’re the only species on the planet,” he said. “On the other hand, we’re always trying to show that we’re not animals. We’re like them, yet we don’t want to be like them.”
Dr. Hauser traces this tension to self-defense. We use animals, and we want to feel justified in using animals. We eat their muscles for meat, flay their hides for shoes and accessories, inject them with experimental vaccines, genetically engineer them into grotesque morphologies to study human diseases. This requires a certain mental distance.
So we adore our pets and lavish time and money on them. Annual pet expenditures in this country have doubled in the last decade and are now more than $40 billion a year. And then we scold ourselves for our foolish fiscal priorities.
We adore our pets and can come to identify with them so deeply that we attribute to them some truly daffy notions, like the radio listener who called in a comment to Colin Allen, a philosopher and cognitive scientist at Indiana University’s Center for the Integrative Study of Animal Behavior. “She wanted to tell me about how her cat had very gingerly brought in an injured bird to show her, as though to say, It’s hurt, please take care of it,” Dr. Allen said. “I suggested there might be other interpretations for her cat’s behavior.”
Yes, we love our pets and anthropomorphize them to the point where we think our cat might enjoy wearing the mouse hat Halloween costume now on sale at Petsmart.com. And still we abandon difficult pets, and shelters euthanize some 10 million pets a year.
I understand the ambivalence of the human-animal bond. I loved my cats, and I miss them, but I resent them, too, for showing me what a creature of small habits I am, and for reminding me that even love is not enough. Life, like the laundry, will always cool down.
Fossil DNA Expands Neanderthal Range
By NICHOLAS WADE, The New York Times, October 2, 2007
In the Treaty of Tordesillas, Spain and Portugal divided the world outside Europe between them. That was not the first time that two rival groups carved up the globe. More than 50,000 years ago, all the world outside Africa was divided between two archaic human species.
The Neanderthals held sway in Europe and the Near East, bottling up the troublesome ancestors of modern humans in Africa, and Homo erectus dominated East Asia. But a new discovery suggests that this division of the world may not have been quite so clear-cut.
Neanderthals evolved their distinctive features some 400,000 years ago, but these are often hard to detect in fragmentary pieces of bone. Another way of identifying Neanderthals has been developed by Svante Paabo at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.
Even though all fossil bones in museums are heavily contaminated with human DNA, Dr. Paabo has shown that Neanderthal DNA can be picked out and identified. So far, he and others have identified DNA from 13 European Neanderthals.
He and colleagues have now identified Neanderthal mitochondrial DNA in bones at two new sites, they say in an article published electronically in Nature this week. One is Teshik Tash, in Uzbekistan, some 750 miles east of the Caspian Sea and, until now, the easternmost known limit of Neanderthal territory. The other bones are from the Okladnikov cave in the Altai mountains, some 1,250 miles farther east.
This huge extension of the Neanderthal’s known range puts them well into southern Siberia.
Because the mitochondrial DNA sequence of the new finds differs only slightly from that of the European Neanderthals, Dr. Paabo believes that they may have moved into Siberia relatively late in the Neanderthal period, perhaps as recently as 127,000 years ago, when a warm period made Siberia more accessible.
If Neanderthals penetrated as far as Siberia, might they have reached ever farther east, trespassing far into the assumed domain of Homo erectus? “We now know that they are on the doorstep to Mongolia and even China, so I would not be surprised if we one day find a Marco Polo Neanderthal,” Dr. Paabo said in an e-mail message. “Conceivably, they may even have contributed to the extinction of H. erectus forms in Asia.”
But Richard Klein, a paleoanthropologist at Stanford University, said the many archaic human fossils of this period from China “bear no resemblance to the Neanderthals.” Any DNA from these fossil bones would be interesting, Dr. Klein said, but “I’d be amazed if it was Neanderthal-like.”
Arctic Melt Unnerves the Experts
By ANDREW C. REVKIN, The New York Times, October 2, 2007
The Arctic ice cap shrank so much this summer that waves briefly lapped along two long-imagined Arctic shipping routes, the Northwest Passage over Canada and the Northern Sea Route over Russia.
Over all, the floating ice dwindled to an extent unparalleled in a century or more, by several estimates.
Now the six-month dark season has returned to the North Pole. In the deepening chill, new ice is already spreading over vast stretches of the Arctic Ocean. Astonished by the summer’s changes, scientists are studying the forces that exposed one million square miles of open water — six Californias — beyond the average since satellites started measurements in 1979.
At a recent gathering of sea-ice experts at the University of Alaska in Fairbanks, Hajo Eicken, a geophysicist, summarized it this way: “Our stock in trade seems to be going away.”
Scientists are also unnerved by the summer’s implications for the future, and their ability to predict it.
Complicating the picture, the striking Arctic change was as much a result of ice moving as melting, many say. A new study, led by Son Nghiem at NASA’s Jet Propulsion Laboratory and appearing this week in Geophysical Research Letters, used satellites and buoys to show that winds since 2000 had pushed huge amounts of thick old ice out of the Arctic basin past Greenland. The thin floes that formed on the resulting open water melted quicker or could be shuffled together by winds and similarly expelled, the authors said.
The pace of change has far exceeded what had been estimated by almost all the simulations used to envision how the Arctic will respond to rising concentrations of greenhouse gases linked to global warming. But that disconnect can cut two ways. Are the models overly conservative? Or are they missing natural influences that can cause wide swings in ice and temperature, thereby dwarfing the slow background warming?
The world is paying more attention than ever.
Russia, Canada and Denmark, prompted in part by years of warming and the ice retreat this year, ratcheted up rhetoric and actions aimed at securing sea routes and seabed resources.
Proponents of cuts in greenhouse gases cited the meltdown as proof that human activities are propelling a slide toward climate calamity.
Arctic experts say things are not that simple. More than a dozen experts said in interviews that the extreme summer ice retreat had revealed at least as much about what remains unknown in the Arctic as what is clear. Still, many of those scientists said they were becoming convinced that the system is heading toward a new, more watery state, and that human-caused global warming is playing a significant role.
For one thing, experts are having trouble finding any records from Russia, Alaska or elsewhere pointing to such a widespread Arctic ice retreat in recent times, adding credence to the idea that humans may have tipped the balance. Many scientists say the last substantial warming in the region, peaking in the 1930s, mainly affected areas near Greenland and Scandinavia.
Some scientists who have long doubted that a human influence could be clearly discerned in the Arctic’s changing climate now agree that the trend is hard to ascribe to anything else.
“We used to argue that a lot of the variability up to the late 1990s was induced by changes in the winds, natural changes not obviously related to global warming,” said John Michael Wallace, a scientist at the University of Washington. “But changes in the last few years make you have to question that. I’m much more open to the idea that we might have passed a point where it’s becoming essentially irreversible.”
Experts say the ice retreat is likely to be even bigger next summer because this winter’s freeze is starting from such a huge ice deficit. At least one researcher, Wieslaw Maslowski of the Naval Postgraduate School in Monterey, Calif., projects a blue Arctic Ocean in summers by 2013.
In essence, Arctic waters may be behaving more like those around Antarctica, where a broad fringe of sea ice builds each austral winter and nearly disappears in the summer. (Reflecting the different geography and dynamics at the two poles, there has been a slight increase in sea-ice area around Antarctica in recent decades.)
While open Arctic waters could be a boon for shipping, fishing and oil exploration, an annual seesawing between ice and no ice could be a particularly harsh jolt to polar bears.
Many Arctic researchers warned that it was still far too soon to start sending container ships over the top of the world. “Natural variations could turn around and counteract the greenhouse-gas-forced change, perhaps stabilizing the ice for a bit,” said Marika Holland, of the National Center for Atmospheric Research in Boulder, Colo.
But, she added, that will not last. “Eventually the natural variations would again reinforce the human-driven change, perhaps leading to even more rapid retreat,” Dr. Holland said. “So I wouldn’t sign any shipping contracts for the next 5 to 10 years, but maybe the next 20 to 30.”
While experts debate details, many agree that the vanishing act of the sea ice this year was probably caused by superimposed forces including heat-trapping clouds and water vapor in the air, as well as the ocean-heating influence of unusually sunny skies in June and July. Other important factors were warm winds flowing from Siberia around a high-pressure system parked over the ocean. The winds not only would have melted thin ice but also pushed floes offshore where currents and winds could push them out of the Arctic Ocean.
But another factor was probably involved, one with roots going back to about 1989. At that time, a periodic flip in winds and pressure patterns over the Arctic Ocean, called the Arctic Oscillation, settled into a phase that tended to stop ice from drifting in a gyre for years, so it could thicken, and instead carried it out to the North Atlantic.
The new NASA study of expelled old ice builds on previous measurements showing that the proportion of thick, durable floes that were at least 10 years old dropped to 2 percent this spring from 80 percent in the spring of 1987, said Ignatius G. Rigor, an ice expert at the University of Washington and an author of the new NASA-led study.
Without the thick ice, which can endure months of nonstop summer sunshine, more dark open water and thin ice absorbed solar energy, adding to melting and delaying the winter freeze.
The thinner fresh-formed ice was also more vulnerable to melting from heat held near the ocean surface by clouds and water vapor. This may be where the rising influence of humans on the global climate system could be exerting the biggest regional influence, said Jennifer A. Francis of Rutgers University.
Other Arctic experts, including Dr. Maslowski in Monterey and Igor V. Polyakov at the University of Alaska, Fairbanks, also see a role in rising flows of warm water entering the Arctic Ocean through the Bering Strait between Alaska and Russia, and in deep currents running north from the Atlantic Ocean near Scandinavia.
A host of Arctic scientists say it is too soon to know if the global greenhouse effect has already tipped the system to a condition in which sea ice in summers will be routinely limited to a few clotted passageways in northern Canada.
But at the university in Fairbanks — where signs of northern warming include sinkholes from thawing permafrost around its Arctic research center — Dr. Eicken and other experts are having a hard time conceiving a situation that could reverse the trends.
“The Arctic may have another ace up her sleeve to help the ice grow back,” Dr. Eicken said. “But from all we can tell right now, the means for that are quite limited.”
Observatory: In a Primitive Tool, Evidence of Trading in the Pacific
By HENRY FOUNTAIN, The New York Times, October 2, 2007
East Polynesia, those remote eastern Pacific islands like Tahiti, the Marquesas and the Tuamotus, was the last part of the planet to be settled, reached by peoples from the western Pacific who voyaged over broad stretches of ocean in canoes, starting about 4,000 years ago.
There has always been a question of how expert these ocean travelers were — whether the voyages were lucky accidents or purposeful expeditions. Most anthropologists think these voyagers knew what they were doing, but no one knows for certain, nor whether there was extensive cross-ocean trading among the islands once they were settled.
But Kenneth D. Collerson and Marshall I. Weisler of the University of Queensland in Australia provide some clues, through a study of old stone adzes found on the Tuamotus.
The adzes have basalt blades. Since they were found on coral atolls, the basalt had to come from volcanic islands elsewhere. By determining concentrations of trace elements and certain isotopes in each blade, the researchers were able to determine where they came from. The study was published in Science.
Most of the blades were found to have come from four island groups, suggesting there was extensive trading across more than 1,000 miles of ocean. And one of the blades was from much farther away — Hawaii, 2,400 miles to the northwest. Hawaiian oral histories include mentions of long voyages to Tahiti by way of the Tuamotus, so this finding supports those histories — and the idea that the early Polynesian settlers were skillful navigators as well.
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Date: 2007-10-03 05:30 pm (UTC)no subject
Date: 2007-10-02 05:52 pm (UTC)The news accompanying the picture is not so good. :(
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Date: 2007-10-03 04:00 am (UTC)no subject
Date: 2007-10-03 05:29 pm (UTC)no subject
Date: 2007-10-04 03:03 am (UTC)what's sad is I just emailed my mom yesterday saying I thought Minnie would make a cute princess, Zeus a good jester, and her cat Riley a good clown, with links to the petsmart costumes. The mouse was cute, but I thought the others were better. :P