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Today's Top News
Climate Warning as Antarctic Ice Bridge Shatters
An ice bridge which held a vast Antarctic ice shelf in place shattered at the weekend and could herald a wider collapse linked to global warming, a leading scientist has warned.
Cracks show how the Wilkins Ice Shelf is collapsing rapidly due to increased temperatures. It is one of 10 shelves in the Antarctic that have shrunk in recent years (British Antarctic Survey/AP) "It's amazing how the ice has ruptured. Two days ago it was intact," said David Vaughan, a glaciologist with the British Antarctic Survey.
A satellite picture from the European Space Agency showed that a 25 mile-long strip of ice believed to pin the Wilkins Ice Shelf in place had splintered at its narrowest point, about 500 metres wide.
The Wilkins, now the size of Jamaica, is one of 10 shelves to have shrunk or collapsed in recent years on the Antarctic Peninsula, where temperatures have risen in recent decades apparently because of global warming.
The satellite image showed a jumble of huge flat-topped icebergs in the sea where the ice bridge had been on Friday. Mr Vaughan, who landed on the flat-topped ice bridge in January in a ski-equipped plane said change in Antarctica was rarely so dramatic. It was his first - and last - visit to the area.
In January, the remaining ice bridge had been surrounded by icebergs the size of shopping malls, many of them trapped in sea ice. A few seals were visible lolling on sea ice in the low Antarctic sunshine.
The loss of the ice bridge, jutting about 20 metres out of the water and almost 100km (62 miles) wide in 1950, may now allow ocean currents to wash away far more of the Wilkins shelf. "My feeling is that we will lose more of the ice, but there will be a remnant to the south," said Mr Vaughan. Ice shelves float on the water, and can be hundreds of metres thick.
Nine other shelves have receded or collapsed around the Antarctic Peninsula in the past 50 years, often abruptly like the Larsen A in 1995 or the Larsen B, further north, in 2002. Cores of sediment on the seabed indicate some of these ice shelves had been in place for at least 10,000 years.
Temperatures on the Antarctic Peninsula have risen by up to about 3C in the past 50 years, the fastest rate of warming in the southern hemisphere. "We believe the warming on the Antarctic Peninsla is related to global climate change, though the links are not entirely clear," Mr Vaughan said. Antarctica's response to warming will go a long way to deciding the pace of global sea level rise.
About 175 nations have been meeting in Bonn, Germany, since 29 March 29 as part of a push to negotiate a new treaty ahead of the United Nations Climate Change Conference in Copenhagen, from 7 to 18 December of 2009. The current talks end on Wednesday.
The loss of ice shelves does not affect sea levels - floating ice contracts as it melts and so does not raise ocean levels. But their loss can allow glaciers on land to slide more rapidly towards the sea, adding water to the oceans.
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Show All"An ice bridge which held a vast Antarctic ice shelf in place shattered at the weekend and could herald a wider collapse linked to global warming, a leading scientist has warned."
Isn't it Climate Change now? This guy didn't get the memo.
A decade of zero-discernable warming, recent reliable predictions of multi-decadal cooling seems to contradict all the theories like this.
Thomas,
Are you serious? Is that really you? You have been the voice of reason...or maybe, the voice of reason has no credibility anymore.
"The eight warmest years on record (since 1850) have all occurred since 1998, with the warmest year being 2005." http://www.epa.gov/climatechange/science/recenttc.html
"The recent warmth has been greatest over North America and Eurasia between 40 and 70°N. Lastly, seven of the eight warmest years on record have occurred since 2001 and the 10 warmest years have all occurred since 1995." http://www.ncdc.noaa.gov/oa/climate/globalwarming.html#q3
Temperatures have been increasing since the Little Ice Age which peaked 300 years ago and finally ended in 1850. Temperatures are below what they were in the MWP when Greenland was green from 900-1300. The fact that temperatures peaked in 1998 due to a super El Nino and have not increased in the past 10 years, and in fact have decreased is not really important, nor is the fact that the temperatures are warmer than most years since 1850. I mean, we are talking about 1 deg F rise per century which started before man was burning fossil fuels.
The suns quiet now, while the last 50 years before this it was in a very active phase, and a period when temperatures increased, actually, temperatures were dropping from 1945 to 1975 before rising, despite increasing CO2 levels, so even the sun takes a bit of time to effect climate.
Cambridge astrophysicist Nigel Weiss:
Typically, sunspots flare up and settle down in cycles of about 11 years. In the last 50 years, we haven't been living in typical times: "If you look back into the sun's past, you find that we live in a period of abnormally high solar activity," Dr. Weiss states.
These hyperactive periods do not last long, "perhaps 50 to 100 years, then you get a crash," says Dr. Weiss. 'It's a boom-bust system, and I would expect a crash soon."
In addition to the 11-year cycle, sunspots almost entirely "crash," or die out, every 200 years or so as solar activity diminishes. When the crash occurs, the Earth can cool dramatically. Dr. Weiss knows because these phenomenon, known as "Grand minima," have recurred over the past 10,000 years, if not longer."
"ScienceDaily (Mar. 29, 2009) — During the Maunder Minimum, a period of diminished solar activity between 1645 and 1715, sunspots were rare on the face of the sun, sometimes disappearing entirely for months to years. At the same time, Earth experienced a bitter cold period known as the "Little Ice Age."
Were the events connected? Scientists cannot say for sure, but it's quite likely. Slowdowns in solar activity -- evidenced by reductions in sunspot numbers -- are known to coincide with decreases in the amount of energy discharged by the sun. During the Little Ice Age, though, few would have thought to track total solar irradiance (TSI), the amount of solar energy striking Earth's upper atmosphere. In fact, the scientific instrument needed to make such measurements -- a space borne radiometer -- was still three centuries into the future."
How is the sun doing today?
http://science.nasa.gov/headlines/y2009/01apr_deepsolarminimum.htm
"April 1, 2009: The sunspot cycle is behaving a little like the stock market. Just when you think it has hit bottom, it goes even lower.
2008 was a bear. There were no sunspots observed on 266 of the year's 366 days (73%). To find a year with more blank suns, you have to go all the way back to 1913, which had 311 spotless days: plot. Prompted by these numbers, some observers suggested that the solar cycle had hit bottom in 2008.
Maybe not. Sunspot counts for 2009 have dropped even lower. As of March 31st, there were no sunspots on 78 of the year's 90 days (87%).
It adds up to one inescapable conclusion: "We're experiencing a very deep solar minimum," says solar physicist Dean Pesnell of the Goddard Space Flight Center.
"This is the quietest sun we've seen in almost a century," agrees sunspot expert David Hathaway of the Marshall Space Flight Center."
In Russia, scientists are preparing for the next ice age.
Who stands to profit from denying global warming?
The melting of Antarctic ice sheets is not a theory but a fact due to the warming ocean water below the ice sheets. Even an increase in snowfall to balance it would still be consistent with global warming due to the higher moisture capacity of warmer air (a cold Antarctica is as dry as a desert). The net result of all this melting is reduced blockage of the flow of land-based ice to the sea, which will raise sea levels.
There is no way to assess the "reliability" of predictions of multi-decadal cooling until after the fact. I am confident that the underlying warming trend has been offset by the recent lulls in solar activity and El Nino, which should have given us more cooling. When they kick back in the trend will accelerate.
By the way, the memo about renaming global warming as "climate change" was written by a denier in an attempt to make it sound less threatening.
Sounds plausible except ice that is already in the water will not raise the sea levels as much or abruptly as the land based ice sheets that will slide or crash into the ocean when the ice such as wilkins has broken up and melted. That would have to be a very curious scenario if a truly massive sheet of land based ice slid into the sea and how fast the sea level would rise.
How is the USO tour going? Where is Bing?
Two-mile thick ice, almost three-miles thick in Antarctica, flows like really thick taffy. It doesn’t slide or crash anywhere.
I'll try to remember that, but there is research that indicates it will, probably the outer edges near shore lines or where the main glacier flows into the water. And I would think if warming really gets into the ice the water under the ice sheets could create a slick bed to move the ice faster than it is moving now.
There already is water under the Antarctic ice sheet, that is because of the enormous pressure of 2-3 miles of ice allows ice to melt at temperatures below 0 deg C.
The air temperatures are so cold in the Antarctic there is little melting of ice on the surface. For example about half of the Greenland ice sheet is warm enough for surface melting to occur, but the Antarctic land mass is much closer to the 90 degree latitude of the pole and typically less than 5% of the surface, which is in the peninsula, gets warm enough for melting to occur, and that for only a brief period in the Antarctic summer (our winter). Overall, the ice sheet in Antarcrica has been growing, not shrinking, even if some parts of the ice shelves break off. That means the Antarctica's contribution to any sea level rise is 0, if not negative.
The West Antarctic ice sheet, comprising only 12% of the total, is as much as 2500 meters below sea level. It would take significant warming to affect this ice sheet, and as much of the ice sheet is under water, the impact on sea levels would not be as great as if the eastern sheet were to melt.
In the last interglacial warm period, 120,00 years ago, temperatures were much higher than today, and sea level may have been 6 meters higher than today, and the West Antarctic ice sheet may in fact have disintegrated along with significant melting of the ice sheet in Greenland. This is without mans CO2. So it could happen, but if it does, it won't be quick, and it is unlikely due to mans CO2.
During the last ice age, about 15,000 years ago, huge ice sheets covered parts of Eurasia and much of North America,extending as far south a Pennsylvania. As the climate has warmed up, sea level rose about 125 meters at an average rate 2.5cm/yr for roughly 5000 years. Although northern ice sheets melted, the Antarctica ice sheet decreased by only 10%.
In Greenland, which would be more susceptibe to melting, most of the ice sheet is surrounded by mountains, it is not likely to just slide into the sea.
Anyways, the CryoSat satellite loss in 2005 was a great loss. It was to provide high-resolution radar altimeter measurements over the margins of the Antarctic and Greenland ice sheets to test the prediction that Arctic ice is thinning due to global warming and to determine to which extent the Greenland and Antarctic ice sheets are contribution to global sea level rise. It would have alleviated a lot of the concern over this issue. There is a great conspiracy theory there.
It wasn't lost.
Neither Global Warming nor Climate Change are very descriptive of what is happening. Some scientists have been using the more accurate and descriptive term of "Global Climate Disruption."
I think Global Warming is an apt description. That people don't understand that the word "global" means the globe and not their back yards, and hence an average, says more about those people than it does about the larger issue.
In the end, it matters not how descriptive the words are, people will believe what they want to believe...come hell or high water.
It's my understanding that the best way to grasp what's happening is by thinking in terms of increasing climate instability---wetter wet spells, drier droughts, hotter summers and colder winters.
Growing seasons, the migration patterns of birds and sea creatures, ocean currents; all are changing in unforeseen and unpredictable ways, but it's beyond credible dispute that these changes are caused by human activity, largely the burning of fossil fuels and deforestation.
The good news---a relative term---is that these changes are, for a rapidly-closing window of opportunity, susceptible to human efforts to reverse them.
Is there any chance increased ultraviolet through the ozone hole is part of this? Its going to be absorbed by something and eventually emitted as infrared. The "hole" may not technically be there any more, and ozone depleters are under control, but the ozone layer is still something like 30% thinner all over the globe and thinnest at the south pole.
Global Dimming has reduced pan evaporation rates, but I sure can get a bad sunburn in March these days.
A current (2008) interpretation of the IPCC reports worth reading. "Dire Predictions" by Machael Mann and Lee Kump.
Oh my!
oh well
whatever
get over it
Where's mine?
Time is quickly running out!
Global warming is the #1 international security threat to mankind in 2009!
Steve
Global Environmentalist
California USA
http://geocities.com/climatechange777
Let's tax babies and let's tax big corps at double the tax of citizens. After all, 1/3 of the footprint is due to each of these categories (peasants "slash and burn" clearing is 1/3 of the global carbon footprint.)
Nothing can stop this melting, imho. The Ocean in the past was 400 feet higher than it is today. All the conservation in the world will do nothing if you humans cannot control your numbers.
TJ
"All tyranny needs to gain a foothold is for people of good conscience to remain silent." - Thomas Jefferson
The geological record shows that during the era of dinosaurs when the carbon dioxide levels were much higher than now the Earth was much warmer. Large areas were desert. Greenhouse gas warming effect is simple physics so the minority of scientists like physicist Weiss who contradict this probably have an irrational addiction to their big green house gas spewing internal combustion machines. A few cycles of less sunspots and a cooler sun will just partially mask the effects of global warming though some warming will continue. Then when greater sunspots cycles return later in the century there will be a sudden very big rise in temperature. Its interesting that some psychologists who have hypnotized hundreds of people to scenes of the next few centuries show a global warming scenario by the end of the 21st century far worse than the scientists are predicting. Scientists keep finding feedback effects such as methane gas from melting Tundra soil and the melting frozen methane from the ocean floor that will worsen global warming. Evidence shows a massive rise in green house gases as the probable cause of the Permian Extinction and ocean bacteria emitting hydrogen sulfide gas poisoned the Permian atmosphere. Sulfur gas producing bacteria has spread off the coast of Namibia with an almost 1000 kilometers of dead zone. Soon after the end of this century only 1/3rd of the population will be given space in underground and domed cities, the rest will be left to slowly die from the poisoned atmosphere. Those who don’t understand their own shadow side don’t understand the shadow in collective events. Those who deny man caused global warming are threatening the survival of our species. When analysis and intuition agree only fools disagree, when the large majority of scientists and psychics agree that man caused global warming is a threat to our planet then those who deny this are simply reflecting a dangerous delusion. Buddha said that the delusion of egotism is the root of all evil. It is height of selfish egotism to not act to save future generations of this planet from global warming.
Nobody denies CO2 causes some warming, what is contested is the amount of warming and the extent that man is causing it, and we are nowhere near the 2000 ppm levels 55 - 255 million years ago. The world has been in an ice age lasting 2 million years, with periods of interglacials like the present, some of which were much warmer than today. Over the last 600,000 ages, we have had 5 interglacials each lasting on average 12,000 years. The current interglacial is 12,000 years old.
As for methane concerns, see attached:
http://www.co2science.org/subject/p/summaries/permafrostmethane.php
"China, Zhuo et al. (1998), during the Holocene Optimum they determined that temperatures during this period were 2-6°C warmer than at present..... resulted in a retreat of the southern permafrost limit to 100 km north of its current location.
China, Jin et al. (2007) studied the evolutionary history of permafrost in the central and eastern Qinghai-Tibetan Plateau. They conclude that during the Holocene Climatic Optimum, areas of permafrost were about 40-50% of those at present, and that mean annual air temperatures were 2-3°C higher. Likewise, they report that during the MWP "the retreating of permafrost resulted in a total permafrost area of ~20-30% less than at present," and that mean annual air temperatures were "1.5-2.0°C warmer than at present."
Alaska, Muhs et al. (2001) This analysis revealed that the overall picture for Alaska and the Yukon during the peak warmth of the last interglacial was that of "a region with warmer-than-present summers, an absence of permafrost in the interior, and probably greater precipitation in the interior." Based upon the expanded boreal forest ranges in this area, they estimate that summer temperatures were at least 1-2°C warmer than they are presently, and that in some locations summer temperatures may have been as much as 3-5°C higher than they are now.
Atmospheric methane concentrations reconstructed from Antarctic ice core data indicate methane concentrations were at an interglacial minimum on the order of 600 ppb or less, while during the MWP, centered on about AD 1000, they ranged between 600 and 700 ppb, which values are to be compared to values close to 1800 ppb today. Hence, it should be abundantly clear that the warming today could not produce the envisioned catastrophic increases in atmospheric methane concentration (although I must admit to being skeptical about ice core data producing artificially low results for CO2 and CH4)
In fact, recurrent interglacial warmings have not been able to do so over the past 650,000 years that we have been able to track atmospheric methane concentration via Antarctic ice-core data (Loulergue, 2008), even during the prior four interglacials, which experienced maximum temperatures that exceeded those of the Holocene Climatic Optimum by an average in excess of 2°C (Petit et al., 1999)."
If the worst case happens, and 80% of man is eliminated, some people on this site believe it would be a good thing as they are neo-malthusians, believing we are running out of resources and have too many people. I am not one of them.
I am more concerned about the debt we are leaving future generations with, and believe they are more likely to see the end of the current interglacial in the future, than catastrophic warming from mans CO2. I can see them 100 years from now as debt slaves living in igloos during an ice age cursing us for going into debt that they must pay to fight CO2, which was delaying the ice age.
Hello.
debt slaves living in igloos. you just gotta love some of these reality show concepts.
and thomas more being the voice of reason. now there's some fodder for the opening monologue of the tonite show. thomas more, living in texas of all places, suggests "a decade of zero-discernable warming, recent reliable predictions of multi-decadal cooling..." that's quite a mouthful, even for a texan. i'm not sure what part of texas you're living in, maybe pecos, that would give him substance to come up with that one.
anyone denying global warming should go spend a couple of hours on any of the planet's receeding glaciers, watching in wonder, and sadness, at the effects of global warming, a direct result of man's intervention in the life cycle of this planet. just sit there, on your denying ass, in the quiet of the pristine wilderness, save for sound of the melting of ice and the trickles of water upon and into the glacier and the currents of water flowing below the glacier and then call it "multi-decadal cooling" or "climate change" or "slowdowns in solar activity" or "spotless" sunspot days. like going to the restroom or taking a dump or taking a crap or having a morning constitution, you can deny it or you can sugarcoat it any way you want. the end result is the same.
as thomasjefferson states, taxing babies is a step in the right direction. maybe even a tax on stupid people as well.
When Greenland was "green" (warmer) in the MWP the Vikings came and they seemed quite happy about the receeding Glaciers. In fact, when it started getting colder and the glaciers came back, making Greenland not as green, they left. Global Cooling drove them out.
Around 900 AD, the climate in the Northern Hemisphere had become so mild that the North Atlantic Ocean was free of icebergs (this enabled explorers such as the Vikings to cross and colonize Greenland, Iceland and Newfoundland in small ships – by today’s standards). Trees grew 100 km farther north than they do today and the Vikings were able to farm and support a community north of the Arctic Circle. However, from 1500 to 1800 the permafrost and ice had taken over the farmland and the treeline was pushed southward. Sea ice filled the sea and the Vikings were forced to move south. Therefore, the Vikings were affected by naturally occurring changes in the Earth’s climate 800 years ago, yet the average global temperature decreased by only 1 degree Celsius during this period! This period of time was known as the Little Ice Age!
Near the end of the Little Ice Age in North America, the winter of 1784 was the longest and one of the coldest on record. It was the longest period of below-zero temperatures in New England, the largest accumulation of snow in New Jersey, and the longest freezing over of Chesapeake Bay. There was ice skating in Charleston Harbor, a huge snowstorm hit the south, the Mississippi River froze at New Orleans, and there was ice in the Gulf of Mexico. Temperatures today are much more to my liking, and I suspect most of nature agrees.
As for alarmist predictions, I have looked into it with an open mind, the science has such a poor level of understanding of climate, and paleoclimatogical data is so uncertain, not to mention problems with measurements even today, that any forecasting of climate 30 to 100 years from now is not much better than a witch looking into their crystal ball to predict the future. You can not predict what you don't understand. And even IPCC scientists agree doubling CO2 would only cause a 1 deg C temperature rise, thats the consensus, however, the alarmists assume only positive feedbacks that will cause an additional 4 deg C. Unfortunately, they neglect the negative feedback effects of clouds and precipitation systems which will prevent such dramatic warming and are not very well understood so are neglected or minimized by the models (and we have little historical data).
Also, they do not take into account the high solar activity of the last 50 years and the fact that this level of solar activity was not a normal level and that reduced solar activity such as we seem to be in now would occur. Our only source of heat is from the sun, and by IPCC's own admission, their level of understanding of solar forcing is low.
As for taxing babies, I agree with that. Not the first 2 kids, but anymore more than that should carry a heft tax since kids are a tax burden, given they need to get a free education, and it's not like we need a growing population, just enough kids to maintain our population.