While this article is encouraging when looking at the title, they are still pushing that “ice-free summer” meme.
A late-winter expansion of Arctic sea ice is a good example of ice-forming dynamics that could keep the Arctic from hitting a “tipping point” in the near future.
Some scientists have predicted that rising temperatures could create a runaway feedback loop in the Arctic. Sunlight-reflecting ice sheets would give way to sunlight-absorbing water, driving up temperatures and melting even more ice. The Arctic climate would change so dramatically that winter ice couldn’t form again, producing planet-wide ripples in weather patterns.
But some research suggests that other, previously underappreciated forces may stabilize the melt before it’s complete. The Arctic will soon be ice-free in summer, and winter ice will decline, but it won’t suddenly become permanently ice-free.
“Everyone thought there would be a tipping point,” said Dirk Notz, a Max Planck Institute climate scientist. “But that’s too simple.”
…
Tipping-point evidence is stronger for western Antarctica than Greenland, said Notz. But even the absence of a tipping point wouldn’t necessarily be reassuring. “It doesn’t mean Greenland won’t melt away,” he said. “It just means it will happen gradually.”
Read More http://www.wired.com/wiredscience/2010/04/polar-ice-review/
Polar Sea Ice
Dwindling Arctic sea ice and crumbling Antarctic ice sheets are now a common sight. Whether they signal an impending tip, with rapid melts causing Earth’s seas to inundate heavily-populated coastal plains, is debated.
The process appears to accelerate itself: Warming ice melts, which exposes darker areas, causing local temperatures to rise further. But in the Arctic, another feedback may stabilize the ice, wrote Max Planck Institute meteorologist Dirk Notz in PNAS. Though most of the ice “will disappear during summer,” much of it will re-freeze in the winter. Arctic sea ice loss “is likely to be reversible if the climate were to become cooler again.”
But Notz is less optimistic about Antarctic sea ice, its undersides heated by eddying Southern Ocean currents. And the West Antarctic and Greenland ice sheets have shrunk suddenly at least twice in the last several million years, a behavior that’s backed up by climate models. It’s “well possible that a tipping point exists for a possible collapse” for those sheets, wrote Notz. It could “render the loss of ice sheets and the accompanying sea-level rise unstoppable beyond a certain amount of warming.”
Climate ‘Tipping Points’ May Arrive Without Warning, Says Top Forecaster
From a UC Davis press release
Though, my favorite environmental tipping sign is this one :
Saying there are no tipping points for the arctic is as extreme a stance as saying there are. It’s all junk science. There are tipping points in every dynamic system where it suddenly shifts to some new state that was unpredictable from the previous input– the problem is, no one knows where those points are. Saying there are or aren’t tipping points is junk science as it really says nothing at all. Pushed far enough, every system will change to a new mode– the more important question is, will AGW push the arctic far enough? The only honest thing to say is– we don’t know.
O/T but good news, i think.
Excerpts from a small article in a MAJOR Chicago newspaper, regarding glaciers in Glacier National Park:
“He warned many of the rest of the glaciers may be gone by the end of the decade.”
But, here is the stunning last paragraph of said small article.
“The park’s glaciers have been slowly melting away since about 1850, when the centuries-long Little Ice Age ended. They once numbered as many as 150, and 37 of those glaciers were named.
Seems encouraging ?
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My original comment seems to be stuck in moderation ??
So here it is again.
@ur momisugly Jim Steele (16:12:33) :
“Permanently” was the operative word used in the original article.
Your citation does not answer my question.
Bob (Sceptical Redcoat) (13:02:19) :
There’s no GOOD NEWS in the world of AGW promoters. They won’t be happy till the Earth freezes over!
Which should start happening in earnest in about 2,000 years. Why? Orbital mechanics.
Mike Ramsey
Does the ‘runaway feedback loop’ in their model take into consideration that the surface of the ‘sunlight-absorbing water’ becomes nearly parallel to the propagation direction of the incoming solar energy as the north pole is approached?
It seems to me, that as the angle of incidence approaches zero, the percentage of the available solar energy that can be absorbed also approaches zero. In other words, reflection bcomes more dominant and there is less absorbed solar energy available to ‘drive up temperatures’ and ‘melt even more ice’ the closer you get to the north pole.
I’d like to know how or if this variable is handled in their model!
R. Gates (16:43:27) :
RE: Tipping points
Give me proof of one tipping point, ever.
Oh, and by the way, define; “tipping point”.
arch stanton (13:10:27) :
Which scientist(s) predicted the Arctic would “suddenly become permanently ice-free.”
Too late to keep Arctic sea ice from vanishing?
‘It’s hard to see how the system may come back,’ expert says
updated 6:21 p.m. ET, Tues., Feb. 12, 2008
ANCHORAGE, Alaska – Arctic sea ice next summer may shrink below the record low last year and it’s hard to see how it won’t eventually melt away completely, according to a University of Washington climatologist.
http://www.msnbc.msn.com/id/23134090/
‘Frightening’ projection for Arctic melt
The Arctic Ocean could be free of ice in the summer as soon as 2010 or 2015 – something that hasn’t happened for more than a million years, according to a leading polar researcher.
By CanWest News ServiceNovember 16, 2007
QUEBEC — The Arctic Ocean could be free of ice in the summer as soon as 2010 or 2015 – something that hasn’t happened for more than a million years, according to a leading polar researcher.
Louis Fortier, scientific director of ArcticNet, a Canadian research network, said the sea ice is melting faster than predicted by models created by international teams of scientists, such as the Intergovernmental Panel on Climate Change (IPCC).
Fortier told an international conference on defence and security in Quebec City Thursday that the worst-case scenarios are becoming reality.
“The frightening models we didn’t even dare to talk about before are now proving to be true,” Fortier told CanWest News Service, referring to computer models that take into account the thinning of the sea ice and the warming from the albedo effect – the Earth is absorbing more energy as the sea ice melts.
According to these models, there will be no sea ice left in the summer in the Arctic Ocean somewhere between 2010 and 2015.
“And it’s probably going to happen even faster than that,” said Fortier, who leads an international team of researchers in the Arctic looking for clues to climate change.
http://www.canada.com/topics/news/national/story.html?id=c76d05dd-2864-43b2-a2e3-82e0a8ca05d5&k=53683
“R. Gates (16:43:27) :
Saying there are no tipping points for the arctic is as extreme a stance as saying there are. It’s all junk science. There are tipping points in every dynamic system where it suddenly shifts to some new state that was unpredictable from the previous input– the problem is, no one knows where those points are. […]”
Except for the class of dynamic systems that have no tipping points.
http://en.wikipedia.org/wiki/Pendulum
The image of ice emerging from larger bodies of ice (or were those islands) is powerful and beautiful, flowing in a sweep of nature, before our eyes.
Oh, how we wonder, when explanations lacking.
Observation & measurement.
They are scared to buck the consensus even when the info says it is wrong. That is like being called a racist. The truth will set them free. Just say it :” CO2 AGW is BS.” Now lets work on some real problem in the environment: fish depletion and forest diversification.
Yosemite Valley used to be a mile deep in ice, as did Chicago and New York. They both reached their tipping points a long time ago, and I doubt anyone feels badly about it – except for maybe the Sabre Toothed Tigers.
Has anyone taken the trouble to check this man Mike Roddy’s credentials, who posted at 16.03.02, by clicking on his name to reveal his contribution to “The Beast” with “14 Most Heinous Climate Villains.” He appears to be proud of his sick and loathsome Ad Hominem attacks.
With contributions like his I know I am definitely on the right and the righteous side.
Look at his entry for Steve McIntyre
9) Stephen McIntyre, Mathematician
Misdeeds: Despite having no training or field experience in climate science, McIntyre runs the blog ClimateAudit.org, whose mission is to use arcane statistical analyses to break the “hockey stick” reconstruction of historical climate patterns. He recently claimed victory over the Briffa tree ring data controversy, but failed to note that there are at least 15 studies that don’t need tree ring data to show the identical late 20th century hockey stick shape of rising temperatures and CO2 concentrations.
Corporate teats: McIntyre lives in tar sands besotted Canada as a “semiretired minerals consultant,” and served as President of Northwest Exploration Co Ltd before they became CGX Energy, Inc. His funding sources are hidden, since the Canadian government is legally somewhere between Texas and Saudi Arabia, and transparency is not required.
Most egregious lie: “I constructed a variation on the CRU data set, removing the 12 selected cores and replacing them with the 34 cores from the Schweingruber Yamal sample….” The echo chamber goes wild, but neither they nor McIntyre himself have any idea what he’s talking about, since Climate Audit is all about masturbating to numbers. Even Briffa’s tree ring work was later vindicated by something McIntyre never considered: further scientific research.
Comeuppance: Sent to the Maldives, given cement shoes and used to mark the rising tide.
He has similarly sick comments for others who he obviously sees as a major threat, such as James Inhofe, Patrick Michaels, Fred Singer, Roy Spencer, Richard Lindzen Bjorn Lomborg and even our own Lord Monckton.
R Gates wrote:
“Pushed far enough, every system will change to a new mode– the more important question is, will AGW push the arctic far enough? The only honest thing to say is– we don’t know.”
You bring up an important disconnect in the use of the term “tipping point,” so the first thing we need to do is get our terms defined properly. Some people use the term to simply mean a situation where a previously-stable state is changed to a different state, where it then re-stabilizes. Others use the term in the sense of a slippery slope, in which case once you are over the “tipping point” there is an inevitable slide to chaos, destruction, or some similar horrific result.
The scare stories almost always play on general public fear of the latter sense of the term, although when pressed, most advocates would acknowledge that they are really talking about the former.
As to whether we can whether the Arctic will reach a tipping point, we would have to ask what kind of tipping point we are talking about. I think some of the commenters who suggest that there is no known process in nature that results in a tipping point are talking about the latter definition.
Of course, if the former is used in a narrow enough sense, then it simply means good old fashioned change — In other words, the “tipping point” simply becomes a confirmation of the fact that nature is not forever static.
“mike roddy (16:03:02) :
Good article, thanks for citing this.
Tipping points, such as those that could lead to sudden arctic ice disappearance, are less important than feedback loops, which exacerbate GHG caused global warming. Changes could occur in century time scales, not in the abrupt pattern that “tipping point” implies.
The problem is that these changes are going to be very difficult to reverse, since so much CO2 will be in the atmosphere. It may be a slow moving train, but the train’s arrival at 7c (as predicted by the MIT business as usual model) will depopulate this planet, and it won’t be pretty.”
What the AGW crowd calls tipping points is mathematically the local maximum between two local minima of a potential function. By perturbing the state of the system you can push it up, if the perturbation is strong enough you make it over the local maximum and the system will then fall into the potential well behind this wall and stay there as long as it isn’t perturbed again.
The positive feedbacks you and the AGW crowd often quote are not a magical force in this picture that move our state around; but they are depressions in the landscape, in other words, guiding our system state to a lower energy level; to a local minimum.
I hope you get the picture; it would mean that once we push the state over a wall (CO2 emissions being the external force) it follows these depressions, seeking a new minimum (minimum not as in temperature minimum but in potential minimum for the system).
So it makes no sense to say when there no tipping points the feedbacks can still mess things up; there are really only 3 possibilities:
1) there is a tipping point and behind it looms positive-feedback-land and your 7C.
2) there is no tipping point and we already descend into the new state (+7C-land).
3) There is no tipping point but negative feedbacks work against our system state perturbation – the walls around our system state become steeper and cannot be crossed.
(All of this assuming for the moment that CO2 is a significant climate driver)
For a good illustration see here about gradient descent:
http://en.wikipedia.org/wiki/Steepest_descent
Do not underestimate Dirk Notz, read what he says:
“Arctic sea ice loss “is likely to be reversible if the climate were to become cooler again.”
Now that is what I call a bright mind. He does not work at the Max Planck Institute for nothing !!!
Minor point is that his assumption is not backed up yet by a climate model. So grand the man a couple of millions so he can build a model that will generate proof (95% confidence level) that lower temperatures, combined with high CO2 levels may well lead to more ice…
Krugman the economist in his NYT diatribe today mentions a tipping point. The point Joe Romm at Climateprogress referred to as Permanent droughts in southwestern states. The droughts and heat tipped the opposite direction. Floods and mudslides in LA, blizzards from Arizona to Houston and no end to moisture.
Since I am also an economist in addition to other professions, the tipping point that will hurt the most is the coming choking of grants and funding. In fact as disgusting as the state supported forecasts are, I suspect we need to fire some of them. The fetish clause that was inserted in many grant applications included some hypothesis slanted toward warming matters.
Why would someone send research money to PSU when Mann has cheated on archived temp records?
The equities markets destroyed the market price for Enron common share because the financial reports could not be trusted.
Let’s name this crash of warming related funding the Enron effect.
The week in November of the 19th as I recall was a tipping point. It started tipping the wrong way. There was nothing sweeter than private e-mail confessions of error, falsification and DECLINING temps.
One of my favorite moments of the tipping point was around Christmas last year. Nasty winter had taken most of any sort of fun out of the Copenhagen fiasco and around Christmas Joe Bastardi says it is going to get nasty wet and cold in the UK. It is coming hard. Even Jan 1, The Met Office as it started turning nasty said they had no idea what was Joe talking about. The Met Office could greatly improve their forecasts if they stuck with reporting what they could see with their eyes looking out the window.
Briffa’s tree rings are so discredited that even Briffa refuses to publicly defend them. There is nothing to defend. He used a selected sample for crucial data, He cannot find the tree rings used. He used proxies for proxies from 1980 onwards because his proxies were not such when compared with real temp measurement. Pure scientific fraud. A PHD candidate would have been blackballed.
mike roddy (16:03:02) :
Please tell me how a warming of 7 degrees C kills everyone on the planet. Even if it was instantaneous, the human death tool would likely be less than what we had during our two world wars. The warming would be mainly in winter at high latitudes where few people live. Sea level rise would accelerate, but a crawling baby could easily out pace the advancing water.
Of course, it can not happen instantly and there is no evidence that it will happen at all, but if it did over 100 years time, humans would easily handle the physical challenges and survive.
You wrote:
“Alarmists” like myself don’t welcome all of the bad news that has been coming in lately, including record global highs in March. We would rather be wrong. Unfortunately, the probability of that appears to be very, very small.”
How can you have so little evidence that you are right and still insist that you can’t be wrong? And what bad news are you talking about? We have had no significant warming for the last 12 years, aside from the minor ups and down associated with ENSO events. Global sea ice is near the 30 year norm, which is remarkable considering that the satellite record started at the end of a global cooling period and we are now at the end of a warming period. The PDO is likely in the beginning of its cool phase, which resulted in global cooling in the mid-20th Century, despite the rapid increase in atmospheric CO2, so cooling is, once again, almost certain. The sun does not appear to be nearly as active as it was last Century. There is no significant evidence of the vital positive feedbacks required to make CO2 a climate crisis and the evidence is growing for negative (stabilizing) feedbacks. ‘Alarmists’ have been caught ‘cooking’ the books on past and current climate to make it seem worse than it actually is. Sea level is rising slower now than it has for the last 100 years. There is no trend in severe weather. There is no trend in tropical cyclone activity. There is nothing happening out of the ordinary at all! Yet you insist that you can not be wrong about the impending doom.
Seriously…in the face of almost no supporting evidence that you are right, why do you feel that you can not be wrong?
I predict that if we don’t do something immediately at least 9 billion people will die by 2100.
Of course if we do absolutely nothing at all I also predict at least 9 billion people will die by 2100.
Ok so there’s not tipping point.
How about tilting point or leaning point.
If this keeps up warmers won’t have anything left but their climate models.
u.k.(us) (17:18:02) :
I’d say a tipping point is a point in a dynamic system where positive feedbacks take over and push it toward a different balance point. That is akin to pushing the top of a tall glass until its centre of gravity is past the base – it ‘tips’, hence the name.
And to be fair, we are aware of tipping points in our climate. They cause ice ages as far as we can see, and also bring us out of them to interglacials such as the current one. I am not aware of any tipping points that have occurred to turn the climate into some raging fireball, despite many times the CO2 trace we have now. That tells us two things (if true):
1. There is no tipping point that leads to runaway warming. Just none at all. If there were, it would have occurred already, and I am pretty certain it has not.
2. CO2 is not the main driver of temperature.
Oh, yes, and when the temperature was at a particularly high point for a seriously long time, all that nasty evil carbon was actually running around as dinosaurs eating all sorts of other carbon. Only when it got terribly cold (I believe) did they pretty much die out, and get sequestered for millions of years as coal and oil for us to use later on. Neat, that.
“Everyone thought there would be a tipping point,” said Dirk Notz.
Everyone? He needs to get out more often.
“Tipping-point evidence is stronger for western Antarctica than Greenland, said Notz. But even the absence of a tipping point wouldn’t necessarily be reassuring. “It doesn’t mean Greenland won’t melt away,” he said. “It just means it will happen gradually.”
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This is a man in need of an ark.