It is one of a string of shelves that have collapsed in the West Antarctic Peninsula in the past thirty years. The Larsen B became the most well-known ice shelf to collapse, disappearing in just over thirty days in 2002.
In the past 50 years, the western Antarctic Peninsula has been warming by 0.9 degree Fahrenheit (0.5 degree Celsius) per decade. In early 2005, some 75% of the 400 mountain glaciers were in retreat on the peninsula. If the ice on the peninsula melts entirely it will raise global sea levels by one foot (0.3 metres).
Glaciers within the much larger west Antarctic Ice sheet are also starting to disappear. In 2005, after evaluation of data from three glaciers, including Pine Island and Thwaites, the conclusion was that they were losing more ice - mainly through the calving of icebergs - than was being replaced by snowfall, the difference between the mass lost and mass replaced being some 60%. The melting of these three glaciers alone was contributing an estimated 0.01 inch (0.24 millimetres) per year to sea level.
Antarctica contains more than 90% of the world's ice and 70% of the freshwater on Earth. The Antarctic ice sheet is losing as much as 36 cubic miles of ice a year. The west Antarctic ice sheet alone contains enough water to contribute metres of sea level rise. The disappearance of the West Antarctic ice sheet could raise worldwide sea levels by an estimated 20 feet (6.1 metres). In 2001, the Intergovernmental Panel on Climate Change (IPCC) said that collapse of this ice sheet was unlikely during the 21st century. This assessment now seems rather conservative.
References:
Antarctic ice sheet is an 'awakened giant' - New Scientist
Antarctic Ice Sheet Is Melting Rapidly - Washington Post
Increasing Amounts Of Ice Mass Have Been Lost From West Antarctica - Science Daily
Antarctic Ice Shelf Disintegration Underscores a Warming World - NSIDC, University of Colorado
rate
email
print
link to this page
Comments: 66 ( 1 removed by Sam Carana )
I also saw this on the news somewhere.
In addition:
there is this:Lakes Beneath Antarctic Ice Sheets Found To Initiate And Sustain Flow Of Ice To Ocean
And what about this:Scientists Detect Thickening Of West Antarctic Ice Sheet
I think we can all agree the climate is "changing." But that's where the agreement ends. Even IF-- big IF, mankind is to blame for this change there's NOTHING WE CAN DO to prevent it, or mitigate the damage.
Some would like to blame mankind for current global events, even though such events have been around far longer than mankind.
I can't imagine why such faith based beliefs are called "science."
I will look at the other link you have here.
Thank you,
Blessings ~
Rene
I think you did a better job of explaining the menace behind this news.
Anybody live in south Florida? What's your elevation above sea level?
Glad you Both posted...
However, the shelves contribute to holding back the ice sheets. If the shelves melt away, the ice sheets will be more prone to melt into the ocean, which will raise the sea levels.
Nor is it independent of the CO2 levels in the sky above it that raises the ambient temperature of all the players in the drama, which is the whole point.
And these draconian policies would do what to the economy ???
Let's say we achieved that random goal--- what would happen to sea levels ???
NOTHING ! ! ! ! ! ! When talking about a .3% meters rise in sea level, won't flood anything, much less the states of Florida, California, or any other state that has a coast line.
That's not a "solution," it is a call to arms by fueling irrational fears of a whole .3 meters rise--- big deal.
Apparently some people believe we can control the weather by saving toilet paper and driving less *chuckle* what rubes.
From Earthweek.com:
"If there is a little bit more retreat, this last 'ice buttress' could collapse and we'd likely lose about half the total ice shelf area in the next few years," Scambos said.
...
"Western sections of the Antarctic Peninsula have experienced the greatest observed warming anywhere else in the Southern Hemisphere over the past 50 years..."
...
"Climate warming has increased the volume of summer meltwater on top of Wilkins, which has weakened the ice shelf, according to the survey."
[Warming Causes Antarctic Ice Shelf to Shatter March 28, 2008]
Secondly, the policies I propose are beneficial, both for the economy and the environment. Waiting with taking action is only making the multitude of problems associated with global warming worse, and rising sea levels is only one of them.
Finally, iJack, if you have an alternative theory on global warming, feel free to submit it to the IPCC and the wider scientific community, but if your theory comes down to "I don't give a ****" then I don't think they'll be very interested.
Of course not, from YOUR perspective. Try to sell it on the Hill and I'm bettin' you'll get the same word thrown in your face more often than not.
the policies I propose are beneficial, both for the economy and the environment.
Well, that's your spin-- and there is no way you can prove it.
if you have an alternative theory on global warming
Why should I give a shit, eh ??? NO ONE HAS PRODUCED ANY EVIDENCE THAT MANKIND IS TO BLAME FOR GLOBAL WARMING. None whatsoever.
I have already presented my "idea" on the concept of "global warming," but I'll repeat it just for you Sammie old buddy.......
My idea is that we DO NOTHING until these acolytes of the faith based religion of global warming PROVE BEYOND A SHADOW OF A DOUBT that we are to blame and that we have a solution that would actually WORK.
Of course, how could that solution even come about, if we don't fully understand what is happening.
You, nor anyone else has CONCLUSIVE EVIDENCE we should be spending billions and billions and billions of dollars for a booger man that never shows up. You can't prove what causes global warming, all you can do is look at the history of the earth to know there is REASONABL DOUBT about mankind being to blame for such catastrophic events that have been occuring on the planet LONG BEFORE MANKIND EVER SHOWED UP.
example from the article:
"Meanwhile the ice mass in East Antarctica has been roughly stable, with neither loss nor accumulation over the past decade.
Professor Jonathan Bamber at the University of Bristol and colleagues estimated the flux of ice from the ice sheet into the ocean from satellite data that cover 85% of Antarctica's coastline, which they compared with simulations of snow accumulation over the same period, obtained using a regional climate model.
They arrived at a best estimate of a loss of 132 billion tonnes of ice in 2006 from West Antarctica -- up from about 83 billion tonnes in 1996 -- and a loss of about 60 billion tonnes in 2006 from the Antarctic Peninsula."
also note all the uses of "estimate" in the early to mid 70's many "estimates" spoke of an oncoming IceAge... those studies were by many of the same people who now are yelling about global warming.
Politics imply choice, iJack, we choose specific policies because we're convinced they are best. Apart from that, I would love to see more scientific research into the effectiveness of the various policies. Far too little work is being done in that area and I do blame politicians for refusing to fund research into that. Now, more than ever, do we need to implement policies that work and, sadly, few people even bother to think about this.
iJack: "My idea is that [we do nothing until we have proof and spend] billions of dollars.."
Well, we don't have time to wait first and see if catastrophic climate change will indeed be catastrophic. Moreover, we won't be wasting money, but we'll be better off financially. By implementing the right policies, we'll be better off not just in environmental respects, but also economically, healthwise, morally, etc, etc. We'll have more job opportunities and more rewarding work. We'll leave a better legacy for our children. Why spend money on importing polluting fossil fuel, when there are better alternatives that are also cheaper, healthier, as well as less polluting? The Bush administration's support for polluting practices stands in the way of this much-needed move towards better alternatives, yet you don't demand Bush to provide proof and evidence before implementing those policies, did you?
What are you suggesting, Emmett, that people who pollute should be even further supported in those practices, like the Bush administration is doing? Your icon shows the statue of liberty against a US flag. Is that supposed to reflect a view that people who inflict harm should be rewarded for doing that?
Why on earth should we be spending BILLIONS on things we may NEVER have a need to use ???? It is LUDICROUS.
Nice to see you M. --- hoping your life is going better since the last time I saw you.
Just coming off of the rancorous discussion following Chris's article, I am prone to warn against "group think". If the Ice of Antarctica is getting ready to flow into the ocean, we need to know this by a rigorous examination of counter arguments, or alternative explanations. I am not the bearer of such arguments.
What I really want to see is data. How much ice, and where is it? How have conditions changed, and where are these changed conditions positioned relative to the ocean? I tried to find data on the amount of ice held in the ice sheets of Antarctica and Greenland, and I could not. I have searched for data on how much water is held in these ice sheets and how much this water would raise sea levels. I tried to make these evaluations based on data in an old style Atlas showing actual square miles and elevations, and I had to make some very crude simplifying assumptions. I wanted to know "What is the maximum increase in elevation of sea level, if all of the ice melted?" My crude estimate was about 260 feet.
My other desire is to see contour maps that will show the extent of coverage, in the event that sea levels rise dramatically. I know this work has been done, because hints of it glint in the news here and there, but I have never seen it. what I have seen contemplates one foot, two feet, etc. But I am expecting 20 feet or 40 feet or one hundred feet in one massive domino effect event. This is the scale at which a set of contour maps would reveal the danger to civilization as we know.
Of all of the effects of Global Climate Chaos, melting of the major ice sheets is the one that holds sufficient dramatic potential to get people's attention, and sufficient potential damage to bring human life back within the carrying capacity of our planet, and restore humanity to its most primitive survival state. Humanity is likely to survive, but does any one of us want to be the cull in this event?
While there are commentators who dispute the verity of Global Warming, and there are commentators (usually the same) who tell us that humanity is not responsible, I am not much impressed by their arguments. If CO2 has no effect, so what? If we cannot regulate CO2, so what? If Climates around the globe are being disrupted, if ice sheets are softening, if water is lubricating the ice-earth interface, if people lives are being disrupted by shifting rain fall patterns, ecological dependencies are being challenged and new diseases are cropping up throughout the animate world, danger swirls around us that is not about nature, but is about our human capacity to talk to each other and abound with solutions and cooperation. Whatever the cause, whatever the over-arching patterns, humanity has already exceeded carrying capacity and only draconian, selfless action, derived from choices that we humans make as the default stewards of Earth, will spare us from wars, more misery, and the violent conclusion of one of life's great extinction events. Suppose none of the least of the climate dangers fulfills its potential. Suppose that sea levels remain where they are and abundant oil continues to flow for another two centuries (this scenario is exaggerated to extract the meaning), we are still over stuffing the planet with people, crowding out all the other creatures, and when there is finally no more room for any other form of life, we will still encounter devastating contractions in available resources that will kill billions of people. Somehow we must learn to talk to each other, not as self absorbed individuals, not as clan representatives, not as national leaders, but as the stewards of life, responsible for its protection and survival. We must make every necessary effort to embrace every person in a global safety net of food security, water security, physical security and health security, while the resources we have still exceed our actual need, so that when we reach that point of equality, where needs equal resources, we will feel secure enough to share.
I am afraid I have gotten on a rant. Please forgive me all! The vision of Global Climate Chaos as disrupting plane flights and drowning some south pacific islands is just too banal for me. The real danger, and the real cause of Global Climate Chaos, is too much demand for the same resources by a single species. We have exceeded carrying capacity.
Why should we spend billions on supporting the polluting practices of burning fossil fuel, driving in gasoline cars, producing meat? We don't have to spend taxpayers money to improve things, jJack, we need to get the Bush administration to stop spending our taxpayers money to support polluting practices. Government doesn't need to spend money, instead we need a FeeBate policy that adds a fee to things that pollute, with proceeds used to support better local alternatives. Such a policy is budget-neutral, respects consumer choice and uses market mechanisms to sort out what works best where.
The last time oil was all the rage in the public arena of "debate," was 1973 when OPEC first began to flex their muscle. They passed all kinds of greenie meanie silliness legislation, and FORCED the big three in Detroit to make cares more fuel efficent.
I don't think it is a coincidence this madness occured in synchronicity with the introduction smaller lighter cars. Guess what ??? There were unintended consequences of such lunacy that still haunts us today.
By the way, why don't you find out how many deaths are attributable the idiotic restrictions in the form of CAFE, making cars so small and light as to be dangerous?
I'll lay odds another 20-25% accidents/deaths were added to the bliss of eternity, because those tiny little cars offered no real protection. In fact, what happened the first time we got hit by OPEC in 73 ??? People startinig MOSTER SUVs, that's what, and the old law of unintend consequences once again raised its visiage to the hoi polloi.
Lastly there is no valid measurement to prop up your very confused statement--
Such a policy is budget-neutral
*chuckle* I don't suppose you could show me the math that lead you to state such nonsense.
Why should we spend billions on supporting the polluting practices of burning fossil fuel, driving in gasoline cars, producing meat?
I really don't thind we are supporting spending "billions" of dollars to prop up any business. Again, if you can show me something that states the auto industry is "subsidized," plese do.
As for farmers, just thank your luck charms (incredibly delicious, but mostly fluff) farmers ARE subsidized or the price could reasonably be predicted to triple, or more.
This kind of nonsense worries me, jJack. I wonder if there is any logic behind your posting. You talk a lot about force, jJack, did you perhaps have a casual flirt with libertarianism? Let me then wake you up. You support government tax, i.e. taking money by force. You support that a lot of that money is used to subsidize practices that are inflicting harm to ecosystems on a global scale, forcing people from their land and destroying their livelihood. Moreover, this support comes at the expense of the alternatives that we need instead in order to get a cleaner environment. This forces good businesses out of the market and forces consumers to buy polluting products and services. Note that I didn't need to use bold type or capitals to highlight how many times you supported the use of force in the process. If you had the illusion that you were following some libertarian logic, then let this be a wake-up call, jJack, because you are perverting libertarianism in a disgraceful way. If - on the other hand - you are just posting here because some company pays to to do so, I'll just remove your future messages.
http://climatesci.org/2008/03/27/reality-check-on-antarctic-sea-ice/
http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/current.365.south.jpg
http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/global.daily.ice.area.withtrend.jpg
Also, there are different developments in different parts of the continent. The IPCC predicted in 2001 that the Antarctic ice sheet would gain mass in the 21st century, due to increased precipitation in a warming climate. This turns out not to be the case. Research at the University of Colorado at Boulder in 2006 concluded that the Antarctic ice sheet is experiencing an annual loss of up to 36 cubic miles of ice, or 152 cubic kilometers, with the bulk of loss occurring in the West Antarctic ice sheet. While the West Antarctic ice sheet is about eight times smaller in volume than the East Antarctic ice sheet, the development in West Antarctica is most worrying. Temperatures on the West Antarctic ice sheet appear to rise most rapidly and, as said, melting of the West Antarctic ice sheet could raise global sea levels by more than 20 feet.
So, the situation is worse than the IPCC predicted. The IPCC, as Reuters reports, thought that Antarctica would not contribute at all to sea level rise, and in fact predicted a growth of the big ice sheet that covers much of the continent from enhanced precipitation, resulting from increased evaporation from the oceans due to global warming. However, this has turned out not to be the case.
These findings are in line with what is happening to the Greenland ice sheet, which melted at a record rate last year, and with studies of Arctic sea ice, which ebbed to its lowest level ever measured in 2007. Researchers at the University of Colorado at Boulder found that older, thicker Arctic sea ice that lasts from year to year is giving way to younger, thinner sea ice that is more susceptible to melting.
While much of the media focus is on the Arctic, the West Antarctic Ice Sheet is most worrying. Ice loss in Antarctica increased by 75 percent in the last 10 years due to a speed-up in the flow of its glaciers and is now nearly as great as that observed in Greenland, according to a recent study by NASA and two California universities.
Simultaneous warming on Earth and Mars suggests that our planet's recent climate changes have a natural—and not a human-induced—cause, according to one scientist's controversial theory.
Earth is currently experiencing rapid warming, which the vast majority of climate scientists says is due to humans pumping huge amounts of greenhouse gases into the atmosphere.
Mars, too, appears to be enjoying more mild and balmy temperatures.
In 2005 data from NASA's Mars Global Surveyor and Odyssey missions revealed that the carbon dioxide "ice caps" near Mars's south pole had been diminishing for three summers in a row.
Habibullo Abdussamatov, head of space research at St. Petersburg's Pulkovo Astronomical Observatory in Russia, says the Mars data is evidence that the current global warming on Earth is being caused by changes in the sun.
"The long-term increase in solar irradiance is heating both Earth and Mars," he said.
Solar Cycles
Abdussamatov believes that changes in the sun's heat output can account for almost all the climate changes we see on both planets.
Mars and Earth, for instance, have experienced periodic ice ages throughout their histories.
"Man-made greenhouse warming has made a small contribution to the warming seen on Earth in recent years, but it cannot compete with the increase in solar irradiance," Abdussamatov said.
By studying fluctuations in the warmth of the sun, Abdussamatov believes he can see a pattern that fits with the ups and downs in climate we see on Earth and Mars.
Abdussamatov's work, however, has not been well received by other climate scientists.
No Tyler, there's no such suggestion. I don't see why you felt a need to cut-and-paste a one-year-old article from National Geographic here. As the article explains on its next page and as is also explained in another article in National Geographic, temperatures on Mars have increased slightly over a 20-year period due to the action of Martian winds, which is cyclical, caused by Mars' orbital cycles, not by the sun.
There is no correlation between solar activity and the strong warming on Earth over the past 40 years. Claims that this was the case have not stood up to scrutiny, according to this study. Earth temperatures are rising dramatically, without a corresponding rise in any kind of solar activity, neither in ultraviolet output nor in cosmic rays. Sunspots have also been ruled out as cause of global warming in this study.
Reinventing the Wheel
I'll keep your group in mind next time I post articles, cheers!
http://wattsupwiththat.wordpress.com/2008/03/26/evidence-of-a-significant-solar-imprint-in-annual-globally-averaged-temperature-trends-part-1/
http://wattsupwiththat.wordpress.com/2008/03/30/evidence-of-a-significant-solar-imprint-in-annual-globally-averaged-temperature-trends-part-2/
Nah, too much trouble. It would inconvenience large political donors who can afford to manufacture their own science.
All of the presidential candidates understand the climate change issue. All of them have a plan to address it. Obama's and Clinton's plans are similar, and they are very different from McCain's. The issue is not controversial - even politically - anymore. The debate has moved on to solutions. I waste far too much time "debating" with contrarians.
Albedo change is the main reason why the IPCC predict a rapid rise in polar temperatures, particularly in the Arctic, where the retreat of sea ice causes the sea water to be exposed to the sun and capture much of the light that was previously reflected by the ice. Ocean surfaces usually are dark; they have an albedo of about 10-15%. The Antarctic ice sheets, which are white, act like a mirror; the surface albedo on Antarctica can be as high as 90%.
Antarctica receives an average of less than one meter (3 feet) of precipitation each year, but most snow falls within 200 to 300 kilometers (120 to 190 miles) of the coast because the big storm systems can only carry the snow that far. The South Pole gets less than an inch of snow each year. The Antarctic Peninsula, where these dramatic losses have occurred, also has the highest precipitation of the continent, 90 centimeters (36 inches). While the poles only get about 60% of the sunshine that reaches the Equator (since Earth is a sphere), in summer the sun shines for more hours at the poles. If the albedo changed, this long period of exposure to sunlight can cause dramatic loss of ice in summer that will not grow back in the form of snow. Reduced albedo can be caused by loss of ice, uncovering blacker earth and rocks, as well as by dark particles released in the air by the global burning of wood and fossil fuel. [source: Letter from Stephanie]
According to this article in Science Daily, ice core samples taken from Greenland show that between 1880 and the 1950s, the amount of soot that feel on Greenland's glaciers and ice sheets dramatically increased. There was seven times more soot from industry than from forest fires in Greenland snow during this period. What worries me is the impact of industry, aviation, shipping, vehicles and power plants that are all burning fossil fuel and emitting particles and soot. Furthermore, desertification and increased burning of wood adds dust to the atmosphere. When settling down on the ice in Antarctica, this could cause a change in albedo, as discussed in this study that found that a 20th-Century doubling in dust archived in an Antarctic Peninsula ice core parallels climate change and desertification in South America.
A European Union directive was adopted in 2001 that called for an increase in the share of renewables in electricity generation from 13.9% in 1997 to 22.1% in 2010 in the 15 EU countries. That target was later extended to all 25 members, although the overall target was somewhat lowered.
In a January 2007 report by the International Energy Agency (IEA), a body within the Organisation for Economic Co-operation and Development (OECD), a scenario is described with additional policies, forecasting 38% of electricity to be based on renewables for OECD Europe in 2030.
My forecast is for a huge rise in the U.S., particularly for solar power and wind power, perhaps also for geothermal power. The policies I advocate can reduce greenhouse gas emissions in the U.S. by 80% by 2020. While market mechanisms should sort out what works best where, I suggest that such reductions can easily be achieved by switching to electric cars and by generating clean electricity, particularly by means of solar power and wind power, complemented by geothermal power and transforming biowaste into energy and agrichar. Moreover, there would be many benefits of such a policy, including less imports, more employment opportunities, economic growth, better health, better food, more water, etc., on top of the environmental benefits. Did you have a look at the Change our World blog?
http://www.livescience.com/environment/080710-ice-shelf.html
For more, read the story New rifts form on Antarctic ice shelf at CNN. If you go to CTV News, you can read the story and also view a videoclip of this news.
I've heard that the largest icemelt danger comes from the ice covering Greenland, and that its melting would result a 20-foot sea level rise, or something close to that.