Scientists warn on climate tipping points
March 17, 2009(PhysOrg.com) -- A survey of top climate scientists has revealed there is a real chance of key climate tipping points being passed with serious consequences for the planet.
In a major study involving 43 of the world’s leading climate experts, scientists have for the first time worked out the likelihood of one of the major climate thresholds being breached.
Tipping points are used to describe a situation where damage due to climate change occurs irreversibly and at an increasing rate.
In this latest research - published today in the Proceedings of the National Academy of Sciences - the internationally-renowned climate team conclude there is a 1 in 6 chance of at least one threshold being passed with a rise of just 2-4 degrees in global average temperature.
If the average increase in temperature is higher than this, then the probability becomes 1 in 2.
Newcastle University’s Professor Jim Hall, Deputy Director, Engineering, of the Tyndall Centre on Climate Change and one of the five authors of the paper, said the aim was to produce policy-relevant information about the likelihood of a tipping point being toppled.
“For the first time we have managed to quantify the uncertainty of these phenomena and the take-home message is tipping points are serious and should play a key role in policy decision making,” said Professor Hall.
“Think of it as like taking out insurance cover. Insurers use probabilities to work out how much we should pay to protect ourselves in the event of something going seriously wrong.
“And it’s exactly the same for the climate. We have provided real data for these key climate indicators and what this has shown is there are good reasons why we should be taking urgent action now to reduce the possibility of something going catastrophically wrong in the future.”
What the study found
The research team asked 43 climate experts to estimate the likelihood of major impacts to five components of the climate system in the 21st and 22nd centuries under different warming scenarios.
The five systems concerned major changes in the North Atlantic Ocean Circulation, the Greenland and Western Antarctic ice sheets, the Amazon rainforest and El Nino.
The probabilities given by the experts varied, but on average they assigned significant chances to a major tipping point being passed in this or the next century for at least the high to medium warming scenarios.
The authors conclude that uncertainty among experts about the prospect of triggering major changes in the climate system does not necessarily imply that such events are remote.
Newcastle University’s Professor Hall added: “In the past, tipping points have been studied in isolation. Here we have looked at them as one Earth system and how one tipping point being passed may have an impact on the others.”
More information: Imprecise probability assessment of tipping points in the climate system. Elmar Kriegler, Jim W. Hall, Hermann Held, Richard Dawson and Hans Joachim Schellnhuber. Published in: Proceedings of the National Academy of Sciences. http://www.pnas.org/cgi/doi/10.1073/pnas.0809117106
Provided by Newcastle University
Feb 04, 2008 |
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If you watch history progams or study history from a lay point of view it is obvious that the Earth has been warmer many times, even in the geologicaly recent past. Lines like "it was three degrees warmer" occur often. In the times of the dinosaurs it was up to FIFTEEN degrees warmer.
There was no tipping points then, so why now.
To use British Rail's usual excuse of "wrong type of snow" or "wrong type of leaves on the rails" perhaps it is the wrong type of heat! You know, a type previously unknown to man. Shall we call it MANN MADE GLOBAL WARMING HEAT to differentiate it from reality.
Firstly, it's "passed".
Secondly, the reality is not that "at current temperatures everything is melting", as it isn't.
http://www.physor...102.html
Noein/DKA/MsDeeNyer, let's see some current references.
It is only 7 hrs since the first comment, do they come "loaded" with 5/5 after 60 votes?
And as you stated, to properly identify a tipping point you need knowledge of all relevant aspects of the system.
How are we identifying tipping points if we have relatively no knowledge of our climate system?
Didn't these same pinheads fathers claim Global Cooling in the 70's?! When you call them on this thy just say, 'well we have more data now'. Well you will have more data in 30 years from now too.
Of course, since they are the ones that keep publishing this bulls#$%t on their website trying to convince the world that the sky is green, surely you wouldn't put it past them to skew the article ratings?
Human activities produce amounts of greenhouse gases comparable to natural sources. According to the USGS, human activities produced 130 times the amount of CO2 produced by volcanism. Unlike many nature sources of carbon, human sources are largely produced from sequestered carbon that haven't been part of short term carbon cycle for millions of years. Based on this evidence people should be concerned.
Absolutely false. Total human GHG contribution is on the order of 2% total contribution. CO2 is 0.003% the majority is water vapor, which the agw proponents will tell you is meaningless due to the rapidity of precipitation.
Considering that's for the year of 2008, so far 2009 volcanic activity has dwarfed the amount of anthropogenic CO2 produced for the past 3 years and it is March.
Please bring facts and reference to the table, otherwise this continues to be a "he said she said" argument.
Comparison of CO2 emissions from volcanoes vs. human activities.
Scientists have calculated that volcanoes emit between about 130-230 million tonnes (145-255 million tons) of CO2 into the atmosphere every year (Gerlach, 1999, 1991). This estimate includes both subaerial and submarine volcanoes, about in equal amounts. Emissions of CO2 by human activities, including fossil fuel burning, cement production, and gas flaring, amount to about 27 billion tonnes per year (30 billion tons) [ ( Marland, et al., 2006) - The reference gives the amount of released carbon (C), rather than CO2, through 2003.]. Human activities release more than 130 times the amount of CO2 emitted by volcanoes--the equivalent of more than 8,000 additional volcanoes like Kilauea (Kilauea emits about 3.3 million tonnes/year)! (Gerlach et. al., 2002)
Math provided at that link. Current sources range from the DoE to NOAA. All contemporary measurements based on their readings for 2008 and expected growth, which is most likely erroring on the high side after the financial collapse.
I notice you've taken your figures from a large sampling of non-contemporary papers. Unfortunately, since none of them use simmilar measuring equipment, and none of them provide any sort of math showing support for their figures, I'd have to question how up to date you are.
Especially since the majority of your information is significantly dated compared to current known values.
I'm insulted at your lack of effort. You merely lazily tossed off an ad hominem attack at people who disagreed with you. You couldn't even muster up the effort to make a simple argument in your own favor. Why did you even bother typing anything?
Oh, and it would be "denialists" not "denialist". Plural, my friend, plural.
Since the goal is to control populations and overcome independent nation-states, the best method is to create fear and hysteria that is rememdied by implementing the solutions these groups offer. Using these well-tested methods of social engineering seems like a good idea at first, but the problem is that past dictatorships cound't (and didn't) root their claims to authority in science.
For a scientific dictatorship to emerge, it must somehow resolve the paradox of asserting and proving a falsehood in order to gain unjustified power and influence in society.
Thus we see the absurd spectacle of hyserical, bell-clanging doomsayers plastering the international media with single-minded effort. Their entire scheme relies absolutely on negating our sense of reason when analyzing what is occuring around us and what is to be done about it.
Just recognize the root of their will, and you'll understand what all the noise is about. This sort of power didn't work out too well in the 20th century, but a modern totalitarianism is far to tempting a prize for men.
Here's the link. http://www.eia.do...115.html
That alone is more than 12% of the roughly 200 million tons of CO2 coming from volcanoes.
Here's the link. http://volcanoes....ndex.php
So let me get this straight, are you telling me that the amount of CO2 emitted by human activities is correct (30 billion tons) and that volcanoes produce hundreds of times more than that, or are saying that amount produced by volcanoes (145-255 million tons) is correct and humans produce 2% of that amount.
If we consider the later to be correct, than consider this: In 2006 the world consumed 6.771 million tons of coal. Each ton of coal produces nearly 4 tons of CO2. That means that in 2006, roughly 24 million tons of CO2 was produced just from the burning of coal. This is from the EIA. Note the link. (http://www.eia.do...15.html)
That alone is more than 12% of the roughly 200 million tons of CO2 coming from volcanoes.
That is a coal consumption chart. Meaning that you're either ignoring technology and assuming we burn coal in an open pit with no reclaimation, or you have no idea what you're looking at when it comes in table form.
If by reclamation you're referring to carbon sequestering coal fired power plants, they are not around. If your referring to land reclamation, the result is still the same, 12 grams of coal produces 44 grams of CO2. In addition to burning the coal, the machinery that digs it out of the ground and carries it to the place where it is used also produces carbon. If you add that in, you raise the 12% even higher. And we still haven't mentioned the impacts of oil and gas yet.
I think some of the discrepancy in the data is because some people insist on including water vapor.. I think this is wrong. Water vapor is a greenhouse gas, but its concentration is nearly totally dependent on the temperature of the atmosphere. If you go outside and spray water vapor into the air, you%u2019re not going increase the overall concentration of water vapor on planet earth. On the other hand, if you spray CO2 into the air, most of it will still be there after 50 years. Water vapor is basically along for the ride. When the climate warms, more water vapor enters the atmosphere, when the earth cools, it drops out.
http://www.timeso...0442.ece
Who will understand the true danger? The greatest threat to humans and the evolution of our sentient mind is and will always be when evil men and women bring madness to reign.
I hope you wake up from false security and understand the dragon that is stirring under cover of "ecology" and "sustainability". Pause the empirical debate for a moment and consider the larger concept: The idea that human beings be reduced to a fraction of their present number.
Before you do anything else, mete the response to statements made by those in public positions such as Jonathon Porritt.
Not even in the most bloodthirsty days of Hitler's insanity did he dare publicly describe the dark plot of his "final solution."
Never would any of the psychotic tyrants of the 19th and 20th centuries have even whispered their intentions towards those they murdered.
So how is it that these persons announce in the full sun of day the need to eliminate more human life than was extinguished in our whole aeon of internecine war?
Furthermore, how is it tolerated that those who dare hiss such deformities in public continue to hold publicly funded positions either in government or in state funded schools?
It is an act of self-destruction and treason to legitimize any of these ideas to children of any age. The doctrines of "green socialism" are equal in every way to the indoctrinations of the soviet and the NAZI whose creeds of submission of self to state pressed more human blood into the earth than all the natural acts of climate ever did.
I cannot fathom the lack of outrage grown adults have when presented with the mere suggestion that they must submit their most fundamental rights as living beings and kneel before the most complete tyranny that has ever been forged for the shackling of this world.
You're out of your depth. Water vapor is included because it inhabits the same bands as CO2 and is 20,000 time more prevailent than CO2. Water vapor also brings CO2 out of the atmosphere during precipitation.
Let me ask you a question:
Based on the knowledge that CO2 is a well mixed gas in the troposphere by what mechanism do the deserts lose their heat over night but humid areas retain their heat?
If CO2 is a main driver of climate and is solely responsible for the retention of excess heat energy in our climate, then logic would say that the desert should stay hot over night. Conversely, the humidity of an area wouldn't dictate it's average temperature or it's propensity to gain or lose heat at an exaggerated rate. So this means something is wrong in your assumption.
The reason why the desert drops to freezing at night and humid areas stay just as warm at night as they were during the day is water vapor. Water vapor is THE greenhouse gas. To discount it in any way shape or form is intellectually dishonest, regardless of it's atmospheric half life.
CO2 doesn't have the concentration, nor the physical ability to cause warming to any discernable degree as evidenced by past measurement and observation.
You do know where they measure atmospheric CO2 content, right? Yep, side of an active volcano.
Those scary pictures of power plants belching out thick white "smoke". That's water vapor, or at least 99% of it is.
Human's main effect on ecosystems and climate are through our land use changes, not our industrial exhaust.
Yeah, trying to say the holocaust didn't happen is a pretty poor stance to bring to the table.
If you were to go to west coast of Washington State and put huge amounts of water vapor in the air, by the time the air reaches the Yakima Valley the water would have precipitated out. Thus, there would be no change in vapor pressure. On the other hand, put large amounts of CO2 in the air and it will remain there for many, many years. We have dug into the earth, removed billions of tons of sequestered carbon and put it into the atmosphere. Much of the carbon put into the atmosphere in the 1950%u2019s is still there today. Much of the water put into the atmosphere a week ago has now precipitated. The only way to make a noticeable change in the concentration of water vapor in the air is to raise the overall air temperature. Therefore, water vapor does not cause climate change it acts as a feedback loop.
As far as the dishonesty remark goes, it's just not so. Each comment I made, I believe to be true to best of my knowledge. I can tell that you feel very strongly that climate change is not real. I was interest in your opinions and was listening not just talking. What I have learned from our discussion is this: You don't believe CO2 is an effective enough greenhouse gas to warm the earth, you don%u2019t believe CO2 levels have been accurately measured, and you don't believe humans can produce enough CO2 to change the climate. You made all of those arguments in your comments. Perhaps we will talk again in the future when we've both gathered new and interesting details about this topic. See ya around.
Stop. This is untrue. I know the climate is changing. I think the A in AGCC is falsly applied.
Also not true. CO2 is a very effective greenhouse gas, one need only look at Venus. Difference is there are no other gasses occupying the same absorption spectra that CO2 occupies in the atmosphere of Venus, nor is the concentration on Earth of any significant amount in global temperature change. CO2 is less than 1 percent of our atmosphere, the human added protion of which is less than 1% of the total amount of CO2.
If changing the concentration of CO2 in Earth's atmosphere by 0.0000028% will result in an increase of 5 degrees F then the Earth wouldn't have given rise to man in the first place, let alone allow us to evolve to the point were we can have this conversation.
That's completely correct. There are research papers dating back to 1819 that speak to the concentrations of our atmosphere listing CO2 as high as 500ppm. These are peer reviewed, well understood papers, written by experts in the field at that time. These papers exist in greater volume than any "alarmis" AGW imminent doom paper, yet they never see the front page. Reason: there's no money to be made by the media when all is well.
No, I don't. I do think through construction and land use we can greatly affect the climate of the planet, but not through releasing an innocuous, non-toxic, and completely spectrally masked gas in concentrations lower than the plant life of this planet releases in a single evening.
The biggest fact against CO2 being the driver is that warming has preceded the increases in CO2 levels. This makes it difficult to name CO2 as the driver unless you fudge the graphs like the IPCC did.
No, no it's not. That is unless you've determined a way to generate mass out of nothing by burning coal. To use the weights you've already lain out. 12 grams of top end coal, (highest carbon content) will yield 30 grams of CO2 if combusted at 100% efficiency. That means no carbon ash, no carbon smoke, just h2o co2 and cho3. Problem is there are sulfur impurities, oxygen impurities, etc.
On average 12 grams of coal will actually net about 20 grams of co2.
But Velanarris, your not playing by the rules of consensus :)