Scientists warn on climate tipping points

(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 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 - 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 .

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 to estimate the likelihood of major impacts to five components of the 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. www.pnas.org/cgi/doi/10.1073/pnas.0809117106

Provided by Newcastle University


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Citation: Scientists warn on climate tipping points (2009, March 17) retrieved 20 October 2019 from https://phys.org/news/2009-03-scientists-climate.html
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Mar 18, 2009
Lets look at this from a different point of view---REALITY! instead of computer games.
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.

Mar 18, 2009
Pah. More pseudo-science. This is a glorified opinion survey. It describes its own methods as subjective, with respondents who were self-selected, and whose responses included a high degree of variability. All the statistical analysis paraded about cannot hide the fact that this is no better than a Vogue "Who's the Hunkiest" survey.

Mar 18, 2009
AGW is a scam, paid for with $10 billion annually of government money to pay scientists to support dire predictions. The IPCC was formed by socialists to help form a world government. When AGW collapses, they will find some other excuse to try to establish world rule. The EU is their model. Despite repeated votes by the populations of European countries to reject submitting to EU dominance, Euro-socialists keep the EU process moving forward, ignoring the popular will. The EU elites scorn the populace, and are dedicated only to establishing dominance.

DKA
Mar 18, 2009
We have past the temperature tiping point already. Reality is that at current temperatures, everything is metling and will be completely melted after some time. The current temperatures are not sustainable.

Mar 18, 2009
Has anyone noticed the high, nay, impossible, rating for the last few propaganda screeches on these pages. 4.6/5 after 63 votes on the first day.
It is only 7 hrs since the first comment, do they come "loaded" with 5/5 after 60 votes?

Mar 18, 2009
Reality is that IF tipping points are passed, no one will know until it is too late. That is the nature of tipping points; everything appears normal right up until the tipping point is breached, then things head to hell in a hurry. IMHO, it is similar to what happens in a lake when the air is cooling quickly. Everything is calm and normal until the upper layers of the water cool past a certain point, then all at once, the lake become turbulent as the colder water sinks down. The point at which the water starts moving is the "tipping point". I've seen this phenomenon and it is quite interesting.

Mar 18, 2009
QW is absolutely the biggest scam in history. There is no way that scientists have an adaquate handle of global climate (the Sun cycles as well), to the extent that spending trillions and handing governments socialism, is anywhere close to justified. These buffoons can't even predict the hurricane season anywhere better than a guess, much less comprehend thousand year old cycles. When you consider the minute effect man has (co2) and the lack of understanding in regard to the sun, and why other planets experience cycles, you will see this as a scam.



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.

Mar 18, 2009
...and a survey is not a scientific analysis! This scam was politicised for a reason.

Mar 22, 2009
You denialist belong in the same group as the mentally challenged.

Mar 22, 2009
The strongest case for climate change rests on two pieces of evidence: 1. Carbon dioxide and other greenhouse gases are rising. 2. When greenhouse gas levels reach some concentration, be it 500 ppm or 1000 ppm, our climate will be significantly warmer then before. Both of these facts are undisputable.

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.

Mar 23, 2009
Sorry. My references are below. You can find additional information on the U.S. Department of Interiors website. I didn't offer them earlier because I didn't notice references from the other people that were commenting. Which, by the way, includes your comments.

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)



Mar 23, 2009
You denialist belong in the same group as the mentally challenged.


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.

Mar 23, 2009
The most fatal flaw in the efforts of AGW propagandists is that they are trying to use scientific methodology (or the similtude thereof) as the foundation of new social authority.

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.

Mar 23, 2009
It doesn't sound to me as though you went to the right link. This information comes from the United States Department of Interior, U.S. Geological Survey. They provided the references not the math.

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.
















Mar 23, 2009
It doesn't sound to me as though you went to the right link. This information comes from the United States Department of Interior, U.S. Geological Survey. They provided the references.
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.

Mar 23, 2009
Yes, that is a coal consumption table. That's how much coal the world consumed. Well over 90% of that coal is used to produce electricity. Each time 12 grams of coal is burned (consumed), 44 grams of CO2 is produced. Weather you burn it in a pit or a power plant the chemistry is the same.


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.




Mar 23, 2009
Whispers of the Green Final Solution:

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.

Mar 24, 2009
I would argue with a Denialist as much as I would argue with a flat earther.

Mar 24, 2009
Deserts lose heat by the same mechanism that the rest of the world does. And yes, the lack of water in the atmosphere is responsible for the rapid cooling at night in the desert. And if there were no CO2 in the desert air, it would be even cold at night. The point is that the desert air is lacking water because it was removed by a cooling process. The air was cooled, lost its water and was carried to an area where water was not available. It should be obvious that the mechanisms that control the concentrations of water vapor in the air are much different from the mechanism that control CO2.

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.


Mar 24, 2009
The strongest case for climate change rests on two pieces of evidence: 1. Carbon dioxide and other greenhouse gases are rising. 2. When greenhouse gas levels reach some concentration, be it 500 ppm or 1000 ppm, our climate will be significantly warmer then before. Both of these facts are undisputable.

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.

Mar 24, 2009
Nice posts Arkaleus! :)

But Velanarris, your not playing by the rules of consensus :)

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