Is the non-mitigation of contrails a deliberate policy?

[Trailspotter]

The engine efficiency is irrelevant to the contrail persistence. If the atmospheric conditions are right for this, the contrail will form and persist and, if the conditions are right for this too, spread, regardless of the engine efficiency. And if they are not right, the contrail will dissipate, regardless of the engine efficiency as well. The engine efficiency only affects the life-time of a non-persistent contrail. The more efficient the engine, the cooler its exhaust. Therefore the vapor concentration in the exhaust is less diluted by the atmospheric air by the time when it has cooled to the temperature, at which vapor begin to condense. This means that at the equivalent atmospheric conditions, a more efficient engine generates a denser contrail, that takes longer time to dissipate. And longer time means longer contrails. If contrail dissipates, say, in just five minutes, its length will reach about fifty miles.

[Mick]

Please don't get into epistemology. It's pointless. There's no absolute proof, only very strong convincing evidence. There's no absolute knowledge, only strongly justified beliefs. There's also a range of qualities of both evidence and justified beliefs.

Okay? Now can we discuss what are the agreed-upon facts, help each other where there are gaps, and narrow down where the real disagreement is?

[George B]

Because they don't know what the quantitative effect of that slight increase in contrails is across all domains, nor do they know the costs of effects of mitigation attempts.

And scientists research, they don't legislate. Since mitigation would cost the airlines money, it requires legislation. Since the scientists don't know much about it, they can't yet present a good argument either way.

But you think someone figured it out 20 years ago?

I am quite aware that scientists don't make policy . . .what I do know is that science is used to justify policy . . . it is clear to me there was a decision to ignore the increase in persistent trails and more cirrus cloud overcast in favor of limiting greenhouse gases and burning less fuel . . . on the part of the airlines this was easy because it added to their bottom-line . . . for the regulatory agencies and the behind the scenes policy wamps could have been different motives . . .

1) An opportunity to experiment with the use of commercial aircraft to see how local temperature range perturbations could be manipulated
2) To see if Global Dimming could be influenced by the high altitude influences of aviation and how it affected Global Warming

[Mick]

The engine efficiency is irrelevant to the contrail persistence. If the atmospheric conditions are right for this, the contrail will form and persist and, if the conditions are right for this too, spread, regardless of the engine efficiency. And if they are not right, the contrail will dissipate, regardless of the engine efficiency as well.

Agreed.

The engine efficiency only affects the life-time of a non-persistent contrail.

Disagree. Engine efficiency ALSO affects whether a contrail forms at all. The air can be ice-supersaturated, but if the exhaust is very hot, then it might never pass though the dew point as it mixes with the cold drier air.

Consider these charts from NASA

http://science-edu.larc.nasa.gov/con...on_English.pdf



The line B->A shows the cooling and drying of air via mixing with ambient air. I've added the point B' for comparison with the gray mixing line. Now this is just hotter, as the engine is less efficient, so more energy is expelled as heat in the exhaust. So this shifts the cooling line, so B'->A never enters the region of water supersaturation, so never condenses, and so no water forms and nothing freezes, so no contrail at all is formed.

The more efficient the engine, the cooler its exhaust. Therefore the vapor concentration in the exhaust is less diluted by the atmospheric air by the time when it has cooled to the temperature, at which vapor begin to condense. This means that at the equivalent atmospheric conditions, a more efficient engine generates a denser contrail, that takes longer time to dissipate. And longer time means longer contrails. If contrail dissipates, say, in just five minutes, its length will reach about fifty miles.

If you look at the diagram, you can kind of see this visually (B->A1 is a short-persistence contrail), the cooler the exhaust, the longer the exhaust gases will have in the condensation region, so more and/or bigger water droplets can form and freeze. So this will certainly change the density and lifetime of the contrail. But it can also make the difference between contrail and no-contrail.

[Mick]

I am quite aware that scientists don't make policy . . .what I do know is that science is used to justify policy . . . it is clear to me there was a decision to ignore the increase in persistent trails and more cirrus cloud overcast in favor of limiting greenhouse gases and burning less fuel . . . on the part of the airlines this was easy because it added to their bottom-line . . . for the regulatory agencies and the behind the scenes policy wamps could have been different motives . . .

It maybe be clear to you, but it's not clear to anyone else.

It simple seems to me like something where the science is not in, it's not a big deal anyway, and government has simply not addressed it. They have not chosen to ignore it, it's simply not even come to their attention.

I guess your point is that you think it's obvious that government would have introduced contrail reduction legislation by now, unless they have some secret motive not to? Is that what you think?

[George B]

It maybe be clear to you, but it's not clear to anyone else.

It simple seems to me like something where the science is not in, it's not a big deal anyway, and government has simply not addressed it. They have not chosen to ignore it, it's simply not even come to their attention.

I guess your point is that you think it's obvious that government would have introduced contrail reduction legislation by now, unless they have some secret motive not to? Is that what you think?

In some ways, Yes . . . this noise is below the radar screen of legislation and that is where the policy people want to keep it . . . "we don't want no stinkin legislation" . . . they don't want their hands tied . . .

[Mick]

But how have you determined that this is the case?

[George B]

But how have you determined that this is the case?

That is ultimately the rub isn't it . . . no absolute empirical evidence to prove or disprove . . . I guess one has to use the proverbial right brain . . . knowledge of human behavior, institutional proclivities, historical precedence, etc . . . it fits into my intuitive constructs and does not fit in yours . . . I see possible manipulation you see . . . simply things just bungling along . . .

I think IPCC and the people behind IPCC are more capable than you do . . . I believe IPCC influences the direction and strength of national strategies to cope with Global Warming . . .

The Intergovernmental Panel on Climate Change (IPCC) is a scientific intergovernmental body^[1][2] first established in 1988 by two United Nations organizations, the World Meteorological Organization (WMO) and the United Nations Environment Programme (UNEP), and later endorsed by the United Nations General Assembly through Resolution 43/53. Its mission is to provide comprehensive scientific assessments of current scientific, technical and socio-economic information worldwide about the risk of climate change caused by human activity, its potential environmental and socio-economic consequences, and possible options for adapting to these consequences or mitigating the effects.^[3] It is chaired by Rajendra K. Pachauri.
http://en.wikipedia.org/wiki/Intergo...Climate_Change

[Mick]

I think the IPCC is as capable as their output indicates. They admit to a lot of uncertainty regarding contrails and climate, the science is just not in yet. That's not lack of capability, it just takes time, especially when you are dealing with system that has oscillations measured in decades.

You seem to think there's some secret super-capable parallel version of everything that had everything figured out 20 years ago.

[Noble1965]

But how have you determined that this is the case?

magical intuition...of course!

[SR1419]

thanks for clarifying: but maybe you put the emphasis in the wrong place - I think I demonstrated quite clearly that 'global coordination of any sort' (Your exact words)is the norm. This would be in direct contradiction of your statement. It shows where your bias is; it is easy to see that your position is not correct, but you prefer to believe this to be the case rather than knowing it to be so - as it so clearly is not so.
You also said:

Global commerce is easy.

global regulation? ...not so much.

Again, your assertion is easily taken apart. Are you saying there is no regulation in global commerce? Come now - I think you really need to check your logic, judgement etc. Statements like these are bordering on disingenuous. But they do provide opportunity to expose your cognitive bias.

Sigh...try and keep up...I amended my comment to say "of THIS sort"- ie; global regulation of emissions etc...You need to go back and read the thread for clarity and comprehension.

Your "demonstration" involved one example...I am sure you can see the problems with a single example being put forth as "the norm"- Global regulation is NOT easy. One only need to look at the difficulties of Kyoto, fisheries management and even in the WTO where it literally takes decades to come to an agreement.

Alas, your failed point is moot - as there is no deliberate non-mitigation of persistent contrails to exact a purposeful outcome.

[Trailspotter]

Mick,

thank you for the correction. I'm aware of the possibility of no-contrail for a very hot exhaust. My point was that newer, more efficient engines do not result in more persistent contrails, as stated, for example, in a chart in the George's post above. They merely produce longer contrails in the conditions where contrails do not persist and dissipate without spreading into cirrus clouds.

[George B]

I think the IPCC is as capable as their output indicates. They admit to a lot of uncertainty regarding contrails and climate, the science is just not in yet. That's not lack of capability, it just takes time, especially when you are dealing with system that has oscillations measured in decades.

You seem to think there's some secret super-capable parallel version of everything that had everything figured out 20 years ago.

The capability is not secret . . . but some of the findings may be . . . we only see them telegraphed

http://en.wikipedia.org/wiki/System_dynamics

System dynamics is an approach to understanding the behaviour of complexsystems over time. It deals with internal feedback loops and time delays that affect the behaviour of the entire system.^[1]What makes using system dynamics different from other approaches to studying complex systems is the use of feedback loops and stocksand flows. These elements help describe how even seemingly simple systems display baffling nonlinearity.

The second major noncorporate application of system dynamics came shortly after the first. In 1970, Jay Forrester was invited by the Club of Rome to a meeting in Bern, Switzerland. The Club of Rome is an organization devoted to solving what its members describe as the"predicament of mankind" -- that is, the global crisis that may appear sometime in the future, due to the demands being placed on the Earth's carrying capacity (its sources of renewable and nonrenewable resources and its sinks for the disposal of pollutants) by the world's exponentially growing population.At the Bern meeting, Forrester was asked if system dynamics could be used to address the predicament of mankind. His answer, of course, was that it could.On the plane back from the Bern meeting, Forrester created the first draft of asystem dynamics model of the world's socioeconomic system. He called this modelWORLD1. Upon his return to the United States, Forrester refined WORLD1 inpreparation for a visit to MIT by members of the Club of Rome.Forrester called the refined version of the model WORLD2. Forrester publishedWORLD2 in a book titled World Dynamics.^[2]

[Mick]

Mick,

thank you for the correction. I'm aware of the possibility of no-contrail for a very hot exhaust. My point was that newer, more efficient engines do not result in more persistent contrails, as stated, for example, in a chart in the George's post above. They merely produce longer contrails in the conditions where contrails do not persist and dissipate without spreading into cirrus clouds.

Aha. Well that also depend on if it's:

(more persistent) contrails - i.e. contrails that last longer

or

more (persistent contrails) - i.e. a larger number of contrails that persist.

George?

(and to confuse matters, NASA's middle classification of contrail - persistent non-spreading, is really just a non-persistent contrail that lasts a long time. The point A1 and A2 are in the same region, just A2 is closer to ice saturation. Poor use of persistent really. Maybe they should be "fading", or "growing" contrails. )

Edit - and actually more efficient engines DO produce both of the cases listed above, as it makes the fading contrails persist longer, and will result in slightly larger numbers of both types of contrails.

[Trigger Hippie]

LoL . . . I never met a scientist, politician, physician or any professional that did not disagree with someone's theory not their own . . . theirs the only one that has any chance to be correct . . .

What a ridiculously naive and ignorant comment suggesting all professionals only accept their own theories. Perhaps you are projecting your inability to accept any theory but your own.

[lee h oswald]

And scientists research, they don't legislate. ...Since the scientists don't know much about it, they can't yet present a good argument

For some context, let's not forget that scientists are people, not some kind of super-race with a direct line to the truth. Like everyone they need to house, feed and cloth themselves; they are just as much slave to the system as anyone - perhaps even more so given the environment in which they earn their living. They need funding (pay) for their work. It is true that most people, scientists alike, would not wish to jeopardise their future employment prospects with their current employer. It is true most scientists are funded either by corporations, whose only goal is to maximise profit; or, the other major hirer and firer of scientists: the government - and they work for the corporations, quite literally in many cases for many a year. Isn't it likely that corporations might act in their interest rather than yours? Isn't it patently clear that this is the case? The human factor.

You like to imbue scientists with some kind of mythical status, but they are subject to all the faults of humanity, at the least. You do it through this quasi-worship you pay to science and nothing else. Therein lies a grave fault in your assessment, for science does not forgive or make allowance for human weakness, condition etc. Therefore it does not recognise the role of what it is to be human as a factor in its workings. Science can only ever give you one small part of the 'truth' of a matter such as this. Science, also, has been quite spectacularly wrong countless times, and will continue to be for as long as it exists. Science is just a mutable, transient state of our understanding of something we feel we need to understand - it will be falsified and superceded at some point....always at some point...

[George B]

Mick,

thank you for the correction. I'm aware of the possibility of no-contrail for a very hot exhaust. My point was that newer, more efficient engines do not result in more persistent contrails, as stated, for example, in a chart in the George's post above. They merely produce longer contrails in the conditions where contrails do not persist and dissipate without spreading into cirrus clouds.

FORMATION, PROPERTIES AND CLIMATIC EFFECTS OF CONTRAILS
^{http://aero-net.info/fileadmin/aeron..._Contrails.pdf Page 17}

10. MITIGATION OPTIONS

The main contrail induced climate problem identified so far is the greenhouse effect of contrailcirrus. Short-lived contrails are less a problem because of very small global area coverage [29].If short contrails are to be avoided for other reasons one has to fly in sufficiently warm and dry atmospheres,as indicated by the Schmidt-Appleman threshold temperature. The introduction of more efficient aircraft engines does not solve the problem of contrail formation; just the opposite is true, because the threshold temperature increases with increased overall efficiency h of the engines[12]. An increased efficiency h is desirable of course for economic and climatereasons by reducing the fuel consumption and reducing emissions of carbondioxide (CO2).

[Mick]

You like to imbue scientists with some kind of mythical status

No I don't.

but they are subject to all the faults of humanity, at the least.

I agree.

You do it through this quasi-worship you pay to science and nothing else.

No I don't.

Scientists are just people. They are people who are good at science. Like carpenters are just people, people who are good at carpentry. I respect anyone who is good at what they do. That does not mean I trust all carpenters equally to do exactly the right thing every time.

Therein lies a grave fault in your assessment, for science does not forgive or make allowance for human weakness, condition etc.

Science has very specifically and explicitly evolved over the years to to make allowances for human weaknesses. That's a very large part of the process of science.

[Mick]

George, when you cut-and-paste something, I'd appreciate it if you accompany it with a clear explanation of what you think it means and how it pertains to the discussion. The above post seems to add nothing at all new.

Hmm, I suppose it's a counterpoint to Trailspotter. But still. Commentary please.

[Trigger Hippie]

for the regulatory agencies and the behind the scenes policy wamps could have been different motives . . .

1) An opportunity to experiment with the use of commercial aircraft to see how local temperature range perturbations could be manipulated
2) To see if Global Dimming could be influenced by the high altitude influences of aviation and how it affected Global Warming

Yes it COULD.

Persistent contrails COULD also be a deliberate government ploy to hide UFO's, the flying spaghetti monster, or an immanent collision with the planet Niburu. Using your standards of evidence and rationale all of these scenarios are equally credible.

[George B]

What a ridiculously naive and ignorant comment suggesting all professionals only accept their own theories. Perhaps you are projecting your inability to accept any theory but your own.

Perhaps you don't live in the real world . . .where humans are imperfect and fall to all types of deception including their own . . .

Are you a professional . . . ? Do you not disagree with your peers on a daily basis . . . . do you not debate the merits of your position and theories above theirs . . . ?

[George B]

George, when you cut-and-paste something, I'd appreciate it if you accompany it with a clear explanation of what you think it means and how it pertains to the discussion. The above post seems to add nothing at all new.

Hmm, I suppose it's a counterpoint to Trailspotter. But still. Commentary please.

Seemed pretty clear to me . . . but I will include comment in the future . . .

[George B]

Yes it COULD.

Persistent contrails COULD also be a deliberate government ploy to hide UFO's, the flying spaghetti monster, or an immanent collision with the planet Niburu. Using your standards of evidence and rationale all of these scenarios are equally credible.

I will repeat what I said above . . . there is no evidence available to prove or disporve the premise for this particular debate . . . it is all inference and supposition . . . I am sorry you have problems with that . . .

That is ultimately the rub isn't it . . . no absolute empirical evidence to prove or disprove . . . I guess one has to use the proverbial right brain . . . knowledge of human behavior, institutional proclivities, historical precedence, etc . . . it fits into my intuitive constructs and does not fit in yours . . . I see possible manipulation you see . . . simply things just bungling along . . .

[Trailspotter]

and to confuse matters, NASA's middle classification of contrail - persistent non-spreading, is really just a non-persistent contrail that lasts a long time. The point A1 and A2 are in the same region, just A2 is closer to ice saturation. Poor use of persistent really. Maybe they should be "fading", or "growing" contrails. .

Well, in my own definition 'persistent contrail' is one that remains in the sky for some time after the (straight flying) aircraft has gone. That is more than 15 minutes old.

[lee h oswald]

1 Your "demonstration" involved one example...I am sure you can see the problems with a single example being put forth as "the norm"-

2 Alas, your failed point is moot - as there is no deliberate non-mitigation of persistent contrails to exact a purposeful outcome.

1 Commerce encapsulates a wide range of activities, not just one, doesn't it?

2 Still no evidence for your assertions. Not one piece, unless you count 'what you say' as evidence.

[Mick]

2 Still no evidence for your assertions. Not one piece, unless you count 'what you say' as evidence.

So you are saying that we can't prove that they didn't deliberately not take action?

What does that even mean?

George just thinks that they would have done some mitigation, and it's suspicious that they have not.

Almost nobody else shares this view.

The scientists say the science is not in. George thinks that secretly it is in.

That's it.

[Trigger Hippie]

there is no evidence available to prove or disporve the premise for this particular debate . . . it is all inference and supposition . . . I am sorry you have problems with that . . .

You are the one suggesting a conspiracy. It's up to you to support you assertion; not me to disprove them. I don`t have a problem with you basing your beliefs on speculation. Although you should.

My position is simple: there is no evidence of a conspiracy. Show me some evidence to the contrary and I`ll change my position.

[Mick]

Well, in my own definition 'persistent contrail' is one that remains in the sky for some time after the (straight flying) aircraft has gone. That is more than 15 minutes old.

Yeah, it's one of those things where there's no commonly accepted definition. Nasa says a persistent contrail is "a thin contrail that remains in the sky after the plane has disappeared", which is a rubbish definition. How long after? And what does "disappeared" mean?

[Trigger Hippie]

Perhaps you don't live in the real world . . .where humans are imperfect and fall to all types of deception including their own . . .

Are you a professional . . . ? Do you not disagree with your peers on a daily basis . . . . do you not debate the merits of your position and theories above theirs . . . ?

You said that scientists, politicians, physicians and all professionals believe their own view is the only one that has any possibility of being correct. If that were true, then we wouldn`t have acceptance of germ theory and evolution. Give it up, your statement is clearly wrong.

[lee h oswald]

Yes it COULD.

If you are the subject of starvation in utero, then you are more likely to suffer diabetes, obesity, high blood pressure etc. in later life. It could be there is a correlation. What do you think? Could there be?

[SR1419]

1 Commerce encapsulates a wide range of activities, not just one, doesn't it?

2 Still no evidence for your assertions. Not one piece, unless you count 'what you say' as evidence.

You suggested buying a potato from Egypt was an example of global coordination - and indeed it is.

I suggested that the regulation of global activities is often difficult to achieve...and indeed it is.

As for the evidence- it has been presented most thoroughly throughout this thread...feel free to scroll back and read lest your bias blind you...

Fact: there is no consensus on the net effects of persistent contrails.

Fact: There is no consensus on effective contrail mitigation techniques.

Fact: there have been NO formal policy discussions by any intra-national or international body capable of implementing any mitigation policy such that a deliberate decision NOT to mitigate was made.


These facts constitute evidence to the aforementioned assertions

[George B]

You said that scientists, politicians, physicians and all professionals believe their own view is the only one that has any possibility of being correct. If that were true, then we wouldn`t have acceptance of germ theory and evolution. Give it up, your statement is clearly wrong.

You are basically talking about consensus acceptance. . . If you think there is absolute acceptance of all the nuances of the theory of evolution . . . You might want to use a different example. . . .my comment is about those issues . . . Absolutes are not found in most human endeavors . . . Experts almost always find issues to disagree about and hotly debate . . . It is their nature. . . .

[lee h oswald]

So you are saying that we can't prove that they didn't deliberately not take action?

What does that even mean?

It doesn't really mean anything, you made it up. It's quite good though. The meaning of my statement: 2 Still no 'evidence' for your assertions. Not one piece, unless you count 'what you say' as evidence? Do we need to recap on the meaning of 'evidence' again?I'm just holding the correspondent to the rules you employ - show me the evidence.for what you say to be true. I see a lot of people saying what they believe, but without concrete facts to put the whole thing to bed once and for all.

[Trigger Hippie]

You are basically talking about consensus acceptance. . .

This is now tedious. I`m talking about scientists accepting theories that are not their own. Something you said never happens.

[Trigger Hippie]

If you are the subject of starvation in utero, then you are more likely to suffer diabetes, obesity, high blood pressure etc. in later life. It could be there is a correlation. What do you think? Could there be?

I don`t know anything about the consequences of prenatal starvation, nor am I in the mood to read about it. As such, I don`t know enough to comment. What`s your point.

[George B]

You suggested buying a potato from Egypt was an example of global coordination - and indeed it is.

I suggested that the regulation of global activities is often difficult to achieve...and indeed it is.

As for the evidence- it has been presented most thoroughly throughout this thread...feel free to scroll back and read lest your bias blind you...

Fact: there is no consensus on the net effects of persistent contrails.

Fact: There is no consensus on effective contrail mitigation techniques.

Fact: there have been NO formal policy discussions by any intra-national or international body capable of implementing any mitigation policy such that a deliberate decision NOT to mitigate was made.

These facts constitute evidence to the aforementioned assertions

So INACTION in the face mounting agitation from citizens and misconceptions about CHEMTRAILs, the slimpicity of some mitigation strategies . . . even trials on an experimental or superficial basis has not been attempted. . . .seems like curiosity alone would have resulted in something. . .

[George B]

This is now tedious. I`m talking about scientists accepting theories that are not their own. Something you said never happens.

I said what I mean. . . I have never found a professional that truly accepted (in total) the theories of another professional in their field of expertise. . . I will stand by that statement. . .

[Spongebob]

That is ultimately the rub isn't it . . . no absolute empirical evidence to prove or disprove . . . I guess one has to use the proverbial right brain . . . knowledge of human behavior, institutional proclivities, historical precedence, etc . . . it fits into my intuitive constructs and does not fit in yours . . . I see possible manipulation you see . . . simply things just bungling along . . .

I think IPCC and the people behind IPCC are more capable than you do . . . I believe IPCC influences the direction and strength of national strategies to cope with Global Warming . . .

The Intergovernmental Panel on Climate Change (IPCC) is a scientific intergovernmental body^[1][2] first established in 1988 by two United Nations organizations, the World Meteorological Organization (WMO) and the United Nations Environment Programme (UNEP), and later endorsed by the United Nations General Assembly through Resolution 43/53. Its mission is to provide comprehensive scientific assessments of current scientific, technical and socio-economic information worldwide about the risk of climate change caused by human activity, its potential environmental and socio-economic consequences, and possible options for adapting to these consequences or mitigating the effects.^[3] It is chaired by Rajendra K. Pachauri.
http://en.wikipedia.org/wiki/Intergo...Climate_Change

Rajendra K. Pachauri.

Rajendra Pachauri , the IPCC chairman often wrongly described in the media as the world leading climate scientist he actually a railway engineer Railway engineer A train driver , a train chauffer ......

http://ktwop.wordpress.com/tag/rajendra-k-pachauri/

http://deathby1000papercuts.com/2010...laim-debunked/

The IPCC are fairly unreliable...

[Trailspotter]

Yeah, it's one of those things where there's no commonly accepted definition.

Agree. This is because contrail behavior is not a property of contrail itself but a consequence of the atmospheric conditions in that particular layer where the contrail is. My "definition" is derived from negation: the contrail cannot be called persistent, while its source is apparent and present in the sky.*

[George B]

Rajendra K. Pachauri.

Rajendra Pachauri , the IPCC chairman often wrongly described in the media as the world leading climate scientist he actually a railway engineer Railway engineer A train driver , a train chauffer ......


http://ktwop.wordpress.com/tag/rajendra-k-pachauri/

http://deathby1000papercuts.com/2010...laim-debunked/

The IPCC are fairly unreliable...

Excellent circumstantial evidence for me. . . .Thanks! The chairman would be very easy to manipulate by experts or political agendas unknown through his lack of technical expertise and life experience. . . A perfect frontman. . . .