EDMONTON, Alberta. A chunk of ice spreading across seven square miles has broken off a Canadian ice shelf in the Arctic, scientists said Tuesday. Derek Mueller, a research at Trent University, was careful not to blame global warming, but said it the event was consistent with the theory that the current Arctic climate isn't rebuilding ice sheets.
"We're in a different climate now," he said. "It's not conducive to regrowing them. It's a one-way process."
Mueller said the sheet broke away last week from the Ward Hunt Ice Shelf off the north coast of Ellesmere Island in Canada's far north. He said a crack in the shelf was first spotted in 2002 and a survey this spring found a network of fissures.
The sheet is the biggest piece shed by one of Canada's six ice shelves since the Ayles shelf broke loose in 2005 from the coast of Ellesmere, about 500 miles from the North Pole. Formed by accumulating snow and freezing meltwater, ice shelves are large platforms of thick, ancient sea ice that float on the ocean's surface. Ellesmere Island was once entirely ringed by a single enormous ice shelf that broke up in the early 1900s.
At 170 square miles and 130-feet thick, the Ward Hunt shelf is the largest of those remnants. Mueller said it has been steadily declining since the 1930s. Gary Stern, co leader of an international research program on sea ice, said it's the same story all around the Arctic.
Speaking from the Coast Guard icebreaker Amundsen in Canada's north, Stern said He hadn't seen any ice in weeks. Plans to set up an ice camp last February had to be abandoned when usually dependable ice didn't form for the second year in a row, he said.
"Nobody on the ship is surprised anymore," Stern said. "We've been trying to get the word out for the longest time now that things are happening fast and they're going to continue to happen fast."
Canadian Ice Shelf Loses 7 Square Mile Section
Can We Bury Global Warming?
When William Shakespeare took a breath, 280 molecules out of every million entering his lungs were carbon dioxide. Each time you draw breath today, 380 molecules per million are carbon dioxide. That portion climbs about two molecules every year.
No one knows the exact consequences of this upsurge in the atmosphere's carbon dioxide (CO2) concentration nor the effects that lie ahead as more and more of the gas enters the air in the coming decades--humankind is running an uncontrolled experiment on the world. Scientists know that carbon dioxide is warming the atmosphere, which in turn is causing sea level to rise, and that the CO2 absorbed by the oceans is acidifying the water. But they are unsure of exactly how climate could alter across the globe, how fast sea level might rise, what a more acidic ocean could mean, which ecological systems on land and in the sea would be most vulnerable to climate change and how these developments might affect human health and well-being. Our current course is bringing climate change upon ourselves faster than we can learn how severe the changes will be.Global Warming Could Increase the Incidence of Kidney Stones
Add kidney stones to the growing list of possible consequences of global warming. A new study warns that as many as 2.3 million more people may develop these mineral deposits in their kidneys by the year 2050 as the result of a warming world. The reason? There's a greater risk that they will be subject to dehydration in more sultry climes, which is believed to be a major contributor to stone formation, according to research published this week in Proceedings of the National Academy of Sciences USA.
"I think the reality of this study is accurate as temperatures do play a great role in stone diseases," says Stephen Nakada, chair of urology at the University of Wisconsin–Madison.
In the U.S., about 10 percent of men and 7 percent of women will develop a kidney stone during their lifetimes. The rate has been rising in recent decades, increasing from 3.6 percent of the overall population in 1976 to 5.2 percent by the mid-'90s. The study notes that this uptick correlates with an increase of half a degree Fahrenheit (0.28 degree Celsius) during the same period.
Most kidney stones form from minerals deposited in the two fist-size organs (located in the lower back on each side of the spine) as they filter urea, mineral salts, toxins and other products from the blood; others form from too much (uric) acid in the urine. Most of the sandlike crystals are tiny enough to exit the kidneys. Larger ones, however, may get stuck in the thread-like ureter that connects each kidney to the bladder, thereby blocking the flow of urine. When blockage occurs, a procedure (usually lithotripsy, which uses a surgical instrument or shock waves) is required to break it into small enough fragments to pass through the thin ureter. Urologists often suggest drinking plenty of water to help flush minerals from the kidneys to prevent stones from forming.
Researchers at the University of Texas Southwestern Medical Center at Dallas, using estimates from the International Panel on Climate Change (IPCC) of temperature swells over the next 40 years, found that the percentage of the U.S. population living in high-risk areas for kidney stones will rise from 40 percent in 2000 to 56 percent in 2050. According to their data, the greatest jump in cases will likely be in the Midwest, with an overall rise in incidence of between 10 and 11 percent.
Study co-author Yair Lotan, an assistant professor of urology, acknowledges that the study is based on estimates that may change. "This means that things may not get as bad as we predict," he says, "or it could be that there will be even more cases of kidney stones than our models tell us."
Nuclear Power Can Stop Global Warming
And unlike a recent Hollywood movie, this is not just a lot of hot air and silly special effects. The planet is warming up; glaciers are melting, ice caps in the Arctic and Antarctic are breaking up, low islands in the Pacific are becoming uninhabitable because of rising sea levels, heat waves and droughts… A seemingly unending litany of natural disasters pointing towards our planet becoming warmer and warmer.
Maybe what we need is a good old fashioned nuclear winter. I’m sure Dubya and his boys would be more than willing to launch a few dozen warheads, kick up a few megatons of fallout and dust to cool the planet a few degrees. Yee ha, stop global warming (excuse me, climate change) and teach those ungrateful Iraqis a little respect for freedom and democracy. Praise the Lord and pass the ammunition.
Panel Supports a Controversial Report on Global Warming
An influential and controversial paper asserting that recent warming in the Northern Hemisphere was probably unrivaled for 1,000 years was endorsed Thursday, with a few reservations, by a panel convened by the nation's pre-eminent scientific body.
The panel said that a statistical method used in the 1999 study was not the best and that some uncertainties in the work "have been underestimated," and particularly challenged the authors' conclusion that the 1990's were probably the warmest decade in a millennium.
But in a 155-page report, the 12-member panel convened by the National Academies said "an array of evidence" supported the main thrust of the paper. Disputes over details, it said, reflected the normal intellectual clash that takes place as science tests new approaches to old questions.
The study, led by Michael E. Mann, a climatologist now at Pennsylvania State University, was the first to estimate widespread climate trends by stitching together a grab bag of evidence, including variations in ancient tree rings and temperatures measured in deep holes in the earth.
It has been repeatedly attacked by Republican lawmakers and some industry-financed groups as built on cherry-picked data meant to create an alarming view of recent warming and play down past natural warm periods.
At a news conference at the headquarters of the National Academies, several members of the panel reviewing the study said they saw no sign that its authors had intentionally chosen data sets or methods to get a desired result.
"I saw nothing that spoke to me of any manipulation," said one member, Peter Bloomfield, a statistics professor at North Carolina State University. He added that his impression was that the study was "an honest attempt to construct a data analysis procedure."
More broadly, the panel examined other recent research comparing the pronounced warming trend over the last several decades with temperature shifts over the last 2,000 years. It expressed high confidence that warming over the last 25 years exceeded any peaks since 1600. And in a news conference here on Thursday, three panelists said the current warming was probably, but not certainly, beyond any peaks since the year 900.
The experts said there was no reliable way to make estimates for surface-temperature trends in the first millennium A.D.
In the report, the panel emphasized that the significant remaining uncertainties about climate patterns over the last 2,000 years did not weaken the scientific case that the current warming trend was caused mainly by people, through the buildup of heat-trapping greenhouse gases in the atmosphere.
"Surface temperature reconstructions for periods prior to the industrial era are only one of multiple lines of evidence supporting the conclusion that climatic warming is occurring in response to human activities, and they are not the primary evidence," the report said.
The 1999 paper is part of a growing body of work trying to pull together disparate clues of climate conditions before the age of weather instruments.
The paper includes a graph of temperatures in the Northern Hemisphere that gained the nickname "hockey stick" because of its vivid depiction of a long period with little temperature variation for nearly 1,000 years, followed by a sharp upward hook in recent decades.
The hockey stick has become something of an environmentalist icon. It was prominently displayed in a pivotal 2001 United Nations report concluding that greenhouse gases from human activities had probably caused most of the warming measured since 1950. A version of it is in the Al Gore documentary "Inconvenient Truth."
Senator James M. Inhofe, Republican of Oklahoma, and Representative Joe L. Barton, Republican of Texas, have repeatedly criticized the Mann study, citing several peer-reviewed papers challenging its methods.
The main critiques were done by Stephen McIntyre, a statistician and part-time consultant in Toronto to minerals industries, and Ross McKitrick, an economist at the University of Guelph in Ontario.
They contended that Dr. Mann and his colleagues selected particular statistical methods and sets of data, like a record of rings in bristlecone pine trees, that were most apt to produce a picture of unusual recent warming. They also complained that Dr. Mann refused to share his data and techniques.
On his Web log, climateaudit.org, on Thursday, Mr. McIntyre said the panel's report seemed to have "two completely distinct personalities," upholding specific criticisms of Dr. Mann's methods, but still positing it was plausible that recent warming exceeded any warm periods for 1,000 years.
In an interview, Dr. Mann expressed muted satisfaction with the panel's findings. He said it clearly showed that the 1999 analysis had held up over time.
But he complained that the committee seemed to forget about the many caveats that were in the original paper. "Even the title of the paper on which all this has been based is as much about the caveats and uncertainties as it is about the findings," he said.
The paper, published in the journal Geophysical Research Letters, was called "Northern Hemisphere Temperatures During the Past Millennium: Inferences, Uncertainties and Limitations."
Raymond S. Bradley, a University of Massachusetts geoscientist and one of Dr. Mann's co-authors, said that the caveats were dropped mainly as the graph was widely reproduced by others. (The other author of the 1999 paper was Malcolm K. Hughes of the University of Arizona.)
The report was done at the request of Representative Sherwood Boehlert, the New York Republican who is chairman of the House Science Committee, who called last November for a review of the 1999 study and related research to clear the air.
In a statement, Mr. Boehlert, who is retiring at the end of the year, expressed satisfaction with the results, saying, "There is nothing in this report that should raise any doubts about the broad scientific consensus on global climate change — which doesn't rest primarily on these temperature issues, in any event — or any doubts about whether any paper on the temperature records was legitimate scientific work."
Critics of the paper remain unconvinced.
A separate panel of statisticians is dissecting Dr. Mann's data and papers for the House Committee on Energy and Commerce, a spokesman for the chairman, Mr. Barton, said.
