Burning all the world’s deposits of

Burning all the world’s deposits of coal, oil and natural gas would raise the temperature enough to melt the entire ice sheet covering Antarctica, driving the level of the sea up by more than 160 feet, scientists reported Friday.
In a major surprise to the scientists, they found that half the melting could occur in as little as a thousand years, causing the ocean to rise by something on the order of a foot per decade, roughly 10 times the rate at which it is rising now. Such a pace would almost certainly throw human society into chaos, forcing a rapid retreat from the world’s coastal cities.
The rest of the earth’s land ice would melt along with Antarctica, and warming ocean waters would expand, so that the total rise of the sea would likely exceed 200 feet, the scientists said.
“To be blunt: If we burn it all, we melt it all,” said Ricarda Winkelmann, a researcher at the Potsdam Institute for Climate Impact Research in Germany and the lead author of a paper published Friday in the journal Science Advances.
A sea level rise of 200 feet would put almost all of Florida, much of Louisiana and Texas, the entire East Coast of the United States, large parts of Britain, much of the European Plain, and huge parts of coastal Asia under water. The cities lost would include Miami, New Orleans, Houston, Washington, New York, Amsterdam, Stockholm, London, Paris, Berlin, Venice, Buenos Aires, Beijing, Shanghai, Sydney, Rome and Tokyo.
Nobody alive today, nor even their grandchildren, would live to see such a calamity unfold, given the time the melting would take. Yet the new study gives a sense of the risks that future generations face if emissions of greenhouse gases are not brought under control.

“This is humanity as a geologic force,” said Ken Caldeira, a researcher at the Carnegie Institution for Science in Stanford, Calif., and another author of the paper. “We’re not a subtle influence on the climate system – we are really hitting it with a hammer.”

Climate scientists have long assumed that countries would recognize the dangers of continuing to dig up and burn the world’s fossil fuels. Yet they have been saying that for 30 years, and political efforts in that time to limit the burning have been ineffectual.

With a major push from President Obama, the nations of the world will convene in Paris in December in another attempt to reach an ambitious deal for reducing emissions. Yet Mr. Obama faces fierce opposition from the Republican Party in putting limits into effect in the United States, which uses more fossil fuels per person than any other large country.

The long-running political gridlock has prompted scientists to start thinking about worst-case scenarios. And recently, major advances have been made in the computerized analysis of the huge ice sheets covering Antarctica and Greenland.

The researchers involved in Friday’s paper decided to use one of these ice-sheet models to attempt the most detailed analysis yet of the potential consequences of burning all fossil fuels. As the first of its kind, the paper is likely to undergo intense scientific scrutiny.

In certain ways, the findings are reassuring. They offer no reason, for instance, to revise the sea-level forecast for the coming century.

A United Nations panel has said that the rise of the sea would not likely exceed three feet in that period, and would probably be less. While some island nations may be wiped out by a rise of that magnitude, experts believe most major cities could be protected from it, though at a likely cost in the trillions of dollars.

The ice sheets respond slowly enough to changes in the climate that it simply takes longer than a century for large-scale melting to begin. But from that point, the paper found, about half the Antarctic ice sheet would melt or fall into the sea in the first thousand years.

“I didn’t expect it would go so fast,” Dr. Caldeira said. “To melt all of Antarctica, I thought it would take something like 10,000 years.”

The more basic finding that the whole ice sheet could eventually melt is less surprising, at least to scientists who specialize in studying the history of the earth. “As a paleoclimate person, I don’t feel like this is necessarily a shock to me,” said Robert E. Kopp, a professor of earth system history at Rutgers University, who studies sea level but was not involved in the new research.

Paleoclimatologists have established that Antarctica was once a lush, green continent, icing over only in the past 35 million years, amid a general cooling of the world’s climate. Moreover, rates of sea level rise like those outlined in the paper have occurred in the past.
Human civilization is built on the premise that the level of the sea is stable, as indeed it has been for several thousand years. But the deeper history of the earth reveals enormous shifts, on the order of a hundred feet or more within a few thousand years.
Sea levels far higher than those of today have been documented at more than a thousand sites around the world. Along the East Coast, seashells from just 3 million years ago can be dug up by the shovel-full a hundred miles inland from the current shore.
Studying this evidence, scientists concluded long ago that the great ice sheets are sensitive to small changes in the earth’s average temperature, caused by wobbles in its orbit around the sun. They believe that human emissions are about to produce a large change.
Though the climate is still in the earliest stages of this shift, the ice sheets in both Greenland and the low-lying, western part of Antarctica are already showing serious signs of instability.
The higher, colder ice sheet in eastern Antarctica, by far the largest chunk of land ice on the planet, had long been assumed to be more stable. But for several years, evidence has been accumulating that at least large parts of that ice sheet are vulnerable, too.

The new study confirms previous findings that how much of the world’s ice will melt is closely linked to how much total fossil fuel humans burn. These studies suggest that a rapid shift away from those fuels over coming decades would preserve much of the ice, or at least slow the melting drastically.
On the other hand, if the use of fossil fuels were to continue rising at the same rate it rose over the past century, the estimated deposits would be burned by about the middle of the 22nd century, Dr. Caldeira said, and complete destruction of the world’s land ice would be well underway.
The exact timing is open to question, he said, but “the idea that most of it would melt, I believe, is a robust result.”

Scientists focus on melting ice in part because the consequences are relatively easy to visualize. But if anything like the scenario in the paper were to play out in the real world, the problems would go far beyond a rise of the sea and a retreat from the coasts.

In a rough calculation, the scientists found that burning all fossil fuels might raise the average temperature of the planet by something like 20 degrees Fahrenheit. Past research suggests that an increase that enormous would likely render vast stretches of the earth too hot and humid for human habitation, cause food production to collapse, and drive much of the plant and animal life of the planet to extinction.

In interviews, scientists said that such long-term risks raise profound moral questions for people of today.

“What right do we have to do things that, even if they don’t affect us, are going to be someone else’s problem a thousand years from now?” asked Ian Joughin, an ice sheet expert at the University of Washington who was not involved in the new research. “Is it fair to do that so we can go on burning fuel as fast as we can?”

Kết quả (Việt) 1:

Đốt cháy tất cả của thế giới các mỏ than đá, dầu mỏ và khí tự nhiên sẽ tăng nhiệt độ đủ để làm tan chảy băng toàn bộ bảng bao gồm Antarctica, lái xe cấp biển lên bởi hơn 160 feet, các nhà khoa học báo cáo thứ sáu.Trong một bất ngờ lớn cho các nhà khoa học, họ tìm thấy rằng một nửa sự tan chảy có thể xảy ra trong ít nhất là một ngàn năm, gây ra đại dương tăng lên của một cái gì đó trên thứ tự của một chân mỗi thập kỷ, khoảng 10 lần tỷ lệ mà tại đó nó đang tăng lên bây giờ. Một tốc độ sẽ gần như chắc chắn ném xã hội con người vào hỗn loạn, buộc một rút lui nhanh chóng từ các thành phố ven biển của thế giới.Phần còn lại của trái đất đất băng sẽ tan chảy cùng với Antarctica, và sự nóng lên biển sẽ mở rộng, vì vậy mà sự nổi lên tất cả biển nào có khả năng vượt quá 200 feet, các nhà khoa học nói."Để được thẳng thừng: nếu chúng ta đốt cháy tất cả, chúng tôi làm tan chảy tất cả," nói Ricarda Winkelmann, một nhà nghiên cứu tại Viện Potsdam cho khí hậu tác động nghiên cứu ở Đức và tác giả của một bài báo được đăng thứ sáu trên tạp chí khoa học tiến bộ.Mực nước biển dâng 200 feet sẽ đưa hầu như tất cả Florida, Louisiana và Texas, toàn bộ bờ biển phía đông Hoa Kỳ, phần lớn của Anh, phần lớn vùng đồng bằng châu Âu, và phần lớn của các châu á ven biển dưới nước. Các thành phố bị mất sẽ bao gồm Miami, New Orleans, Houston, Washington, New York, Amsterdam, Stockholm, London, Paris, Berlin, Venice, Buenos Aires, Bắc Kinh, Shanghai, Sydney, Rome và Tokyo.Không ai còn sống ngày hôm nay, cũng không thậm chí cháu của họ, sẽ sống để chứng kiến tai ương mở ra, cho thời gian sự tan chảy sẽ mất. Được nghiên cứu mới cho một cảm giác của những rủi ro mà phải đối mặt thế hệ tương lai nếu lượng phát thải khí nhà kính không được đưa ra dưới sự kiểm soát."Đây là nhân loại như một lực lượng địa chất,", ông Ken Caldeira, một nhà nghiên cứu tại viện Carnegie khoa học tại Stanford, California, và các tác giả khác của giấy. "Chúng tôi không phải là một ảnh hưởng đến tinh tế hệ thống khí hậu-chúng tôi đang thực sự nhấn nó với một cái búa."Các nhà khoa học khí hậu lâu đã giả định rằng nước nào công nhận sự nguy hiểm của tiếp tục khai thác và đốt cháy nhiên liệu hóa thạch của thế giới. Nhưng họ có nói rằng trong 30 năm qua, và những nỗ lực chính trị trong thời gian đó để giới hạn việc đốt đã không hiệu quả.Với một đẩy lớn từ tổng thống Obama, các quốc gia trên thế giới sẽ triệu tập tại Paris trong tháng mười hai trong một nỗ lực để đạt được một thỏa thuận đầy tham vọng cho việc giảm lượng khí thải. Được ông Obama phải đối mặt với phe đối lập ác liệt từ Đảng Cộng hòa ở đặt giới hạn chế có hiệu lực tại Hoa Kỳ, sử dụng nhiên liệu hóa thạch thêm cho mỗi người hơn bất kỳ quốc gia lớn nào khác.Bế tắc chính trị dài chạy đã nhắc nhở các nhà khoa học để bắt đầu suy nghĩ về kịch bản trường hợp xấu nhất. Và gần đây, tiến bộ lớn đã được thực hiện trong phân tích trên máy vi tính các phiến băng lớn bao gồm châu Nam cực và Greenland.The researchers involved in Friday’s paper decided to use one of these ice-sheet models to attempt the most detailed analysis yet of the potential consequences of burning all fossil fuels. As the first of its kind, the paper is likely to undergo intense scientific scrutiny.In certain ways, the findings are reassuring. They offer no reason, for instance, to revise the sea-level forecast for the coming century.A United Nations panel has said that the rise of the sea would not likely exceed three feet in that period, and would probably be less. While some island nations may be wiped out by a rise of that magnitude, experts believe most major cities could be protected from it, though at a likely cost in the trillions of dollars.The ice sheets respond slowly enough to changes in the climate that it simply takes longer than a century for large-scale melting to begin. But from that point, the paper found, about half the Antarctic ice sheet would melt or fall into the sea in the first thousand years.“I didn’t expect it would go so fast,” Dr. Caldeira said. “To melt all of Antarctica, I thought it would take something like 10,000 years.”The more basic finding that the whole ice sheet could eventually melt is less surprising, at least to scientists who specialize in studying the history of the earth. “As a paleoclimate person, I don’t feel like this is necessarily a shock to me,” said Robert E. Kopp, a professor of earth system history at Rutgers University, who studies sea level but was not involved in the new research.
Paleoclimatologists have established that Antarctica was once a lush, green continent, icing over only in the past 35 million years, amid a general cooling of the world’s climate. Moreover, rates of sea level rise like those outlined in the paper have occurred in the past.
Human civilization is built on the premise that the level of the sea is stable, as indeed it has been for several thousand years. But the deeper history of the earth reveals enormous shifts, on the order of a hundred feet or more within a few thousand years.
Sea levels far higher than those of today have been documented at more than a thousand sites around the world. Along the East Coast, seashells from just 3 million years ago can be dug up by the shovel-full a hundred miles inland from the current shore.
Studying this evidence, scientists concluded long ago that the great ice sheets are sensitive to small changes in the earth’s average temperature, caused by wobbles in its orbit around the sun. They believe that human emissions are about to produce a large change.
Though the climate is still in the earliest stages of this shift, the ice sheets in both Greenland and the low-lying, western part of Antarctica are already showing serious signs of instability.
The higher, colder ice sheet in eastern Antarctica, by far the largest chunk of land ice on the planet, had long been assumed to be more stable. But for several years, evidence has been accumulating that at least large parts of that ice sheet are vulnerable, too.

The new study confirms previous findings that how much of the world’s ice will melt is closely linked to how much total fossil fuel humans burn. These studies suggest that a rapid shift away from those fuels over coming decades would preserve much of the ice, or at least slow the melting drastically.
On the other hand, if the use of fossil fuels were to continue rising at the same rate it rose over the past century, the estimated deposits would be burned by about the middle of the 22nd century, Dr. Caldeira said, and complete destruction of the world’s land ice would be well underway.
The exact timing is open to question, he said, but “the idea that most of it would melt, I believe, is a robust result.”

Scientists focus on melting ice in part because the consequences are relatively easy to visualize. But if anything like the scenario in the paper were to play out in the real world, the problems would go far beyond a rise of the sea and a retreat from the coasts.

In a rough calculation, the scientists found that burning all fossil fuels might raise the average temperature of the planet by something like 20 degrees Fahrenheit. Past research suggests that an increase that enormous would likely render vast stretches of the earth too hot and humid for human habitation, cause food production to collapse, and drive much of the plant and animal life of the planet to extinction.

In interviews, scientists said that such long-term risks raise profound moral questions for people of today.

“What right do we have to do things that, even if they don’t affect us, are going to be someone else’s problem a thousand years from now?” asked Ian Joughin, an ice sheet expert at the University of Washington who was not involved in the new research. “Is it fair to do that so we can go on burning fuel as fast as we can?”