Debunked: Clifford Carnicom's "Contrail Physics"

Mick West

Administrator
Staff member
In this article, Clifford Carnicom make some bold claims:

http://www.carnicominstitute.org/articles/model1.htm

[bunk]1. Contrails composed of water vapor routinely dissipate, as the physics and
chemistry of this model will demonstrate. As a separate and distinct
set of events, clouds may form if temperature, relative humidity, and
aerosol conditions are favorable to their development. If "contrails"
by appearance transform into "clouds", it can be concluded that the
material of composition is not water vapor.

2.The conditions under consideration show that the ice crystals
within a contrail can warm to the melting point and subsequently melt
with the heat provided by solar radiation.

3. As demonstrated both by historical observation and this model, the
time expected for contrail dissipation is relatively short, e.g., 2
minutes or less. This assumes the contrail is composed essentially
of water vapor, per the classic definition (condensed trail).
[/bunk]

If we give Carnicom the benefit of the doubt and assume most of this science is correct, then the conclusion he reaches is that:

- First the water vapor freezes, because it's so cold
- Then it melts and evaporates, because the sun is so hot

So why doesn't is just freeze again, because it's so cold? The condensation nuclei still exist, and are now considerably cooler than when they exited the engine.

He also makes the distinction between clouds and contrails, saying clouds form on smaller condensation nuclei (0.1 to 0.2 microns). To suport this he quotes Goethe MB - Ground Based Passive Remote Sensing of Ice Clouds with Scattered Solar Radiation in the Near Infrared - Max Planck Inst Meteorol, which gives a particle size of 30-200 microns. However that Goethe study is not measuring nuclei (the tiny seed at the heart of an ice crystal), it's measuring the actual fully grown ice crystals.

The condensation nuclei for contrails that come from the exhaust are basically soot and other byproducts of combustion, having a size of 0.1 microns or less.

Hence they will behave exactly the same as clouds. If carnicom has proven here that contrails cannot persist and spread, then, since clouds must start out small and spread to a larger size, he has also proven that cirrus clouds cannot even exist at all.

Then in a second article, The RH Deception
http://www.carnicom.com/rh1.htm

He claims that if the relative humidity is between 70% and 100% then contrails should dissipate in about ten seconds, because at 10% relative humidity it would dissipate in two seconds.
[bunk]Even at a relative humidity level of 70%, which must be considered quite high for the commercial flight domain, a factor of 3.3 against the maximum evaporation rate of a completely arid environment must be considered as relatively minor. Most of us would have a difficult case of making the argument of a persistent vapor trail within a moisture-free environment, and more realistically we would expect dissipation within a matter of seconds (disregarding deliberate aerosol injections). To multiply a few seconds by a factor of 3.3 leads to no real world change in the situation at hand[/bunk]

This is nonsense for two reasons.
1) Evaporation or melting time does not scale like that. It's as if he claimed that since ice melts in ten seconds at 100 degrees, and in five seconds at 50 degrees, then it should melt in about two seconds at zero degrees. Of course it's not actually going to melt at all.
2) If Relative Humidity with respect to water is between 70% and 100% then relative humidity with respect to ice is always above 100%. In that environment ice cannot sublimate. In fact it will always accrete more ice, and the ice crystals will grow bigger, causing the contrail to spread.
 
In the first Carnicom webpage Mick cited, Carnicom is admitting that the ice crystals will form from the water vapor from combustion at flight altitudes of around -50 degrees C.

Then he proceeds to claim that solar radiation at a certain intensity would melt the ice crystal.

Next, he calulates the intensity of solar radiation that he would expect, and applys it to the ice crystal.

However, he treats the ice crystal not as if it remained exposed to the -50 degree air, but as if it were in an imaginary "thermos bottle", with no contact to the continuing cooling effect of the -50C air.

The problem with his "model" is that it doesn't account for the fact that the ice crystals of contrails are not inside an imaginary "thermos bottle", insulated from the outside air, instead they are in the real world, still in contact with the cooling effect of the -50C air, and thus do not melt.

Here is an example of what he is saying-

Carnicom's world:
1- Take an ice cube, then place it in a pan and heat it until it melts.
2- Place the resulting water in a thermos bottle and come back to see if it turns back to ice.

Of course it won't re-freeze, since it isn't exposed to anything that would refreeze it.

Real world:
3. Take another ice cube and melt it.
4. Place the pan in your freezer.

Of course, it will re-freeze, because the freezer is cold enough that the heat you put into the ice is drawn away from the melted ice cube.
 
This is nonsense for two reasons.
1) Evaporation or melting time does not scale like that. It's as if he claimed that since ice melts in ten seconds at 100 degrees, and in five seconds at 50 degrees, then it should melt in about two seconds at zero degrees. Of course it's not actually going to melt at all.
2) If Relative Humidity with respect to water is between 70% and 100% then relative humidity with respect to ice is always above 100%. In that environment ice cannot sublimate. In fact it will always accrete more ice, and the ice crystals will grow bigger, causing the contrail to spread.

In this Carnicom webpage, first of all, he assumes that his previous claim were true, but it was false.

His biggest problem in this second study was that Carnicom hadn't yet realized that there was a difference between RH with respect to water which is used on the ground, and relative humidity with respect to ice, which is what applies at the -40C temperatures at flight levels for contrails.

First of all, Carnicom based his assumptions on data regarding flight levels of 65,000 feet in the stratosphere, twice that of the commercial jets he had documented photographically at around 30-39,000 feet.

Carnicom said:
This is not the case for upper regions of the atmosphere, which is the favored domain of jet aircraft traffic. As a case in point, during congressional hearings regarding the environmental effects of projected supersonic flight traffic at 65,000 ft., the expert testimony explained that "persistent contrails" would not be a factor as the relative humidity at that level commonly is approximately 5%.

The history of this claim by Carnicom is interesting. He put out his "RH Deception", and that's what it really was, in May of 2001.

At that time, there were two main forums which discussed the chemtrails subject, Carnicom's own forum, and chemtrailcentral.com.

Here is Carnicom making his false claims in August 2000. He judges that since there is 36% relative humidity at flight levels, there should be no contrails, or the associated cirrus clouds. He gets confronted by a pilot who explains to him the amount of ordinary air traffic and advises him to track the flights using a tracking program. The pilot is responded to by A.C Griffith, who says:

Continuous debate is non-productive and a waste of time http://chemtrails.yuku.com/topic/1142/A-Contradiction

What is interesting is that Carnicom had already stumbled upon the facts about ice supersaturation in August, 2000:

Clifford Carnicom said:
Re: The Contradiction Remains
(09/09/0014:53:32)
Now five sources:
"Data from a wave cloud at temperatures below -60 C showed that nucleation of ice began at approximately 80% relative humidity with respect to water (~125-130 % saturation with respect to ice), consistent with earlier observations of Heymsfield and Larry Miloshevich in wave clouds at temperatures of -55 C."
www.mmm.ucar.edu/asr96/part_h.html
Clifford E Carnicom
http://chemtrails.yuku.com/reply/10469/The-Contradiction-Remains#reply-10469

Meanwhile, over at chemtrailcentral.com, an actual PhD. Biochemist, a woman from Lubbock, Texas, who went by the screen name of 3T3L1, had begun to believe in chemtrails but examined Carnicom's paper and realized his errors:

3T3L1 said:
Wow! Relative Humidity! I can tell already that this topic is going to be a popular one!
I got into this last night after reading Clifford Carnicom's material called "The RH [Relative Humidity] Deception." http://www.carnicom.com/rh1.htm

It contains equations (not my strong suit) but something about it didn't seem right. Clifford's table of "Persistence Factors" indicated that contrails should last on the order of minutes when the relative humidity is less than 90%. He implies that the only way contrails could last for hours is when the Persistence Factor is near infinity, i.e., when the relative humidity is near 100%, which almost never happens in the upper atmosphere. (As a general approximation, clouds form when the relative humidity is about 70%.)
http://www.chemtrailcentral.com/ubb/Forum14/HTML/000006.html

3T3L1 by September of 2000, with much of the help coming from Dr. Patrick Minnis, probably the most qualified contrail expert in the world, who posted at Carnicom's forum as "Dogbreath", and eventually at chemtrailcentral as Canex (canine exhalations).

3T3L1 eventually got it all figured out and much of what the chemmies understood at that time had been established by October.

Carnicom, however, had his papers reviewed by "dogbreath"(Minnis) who tried to straighten him out at the Carnicom messageboard.
Carnicom banned Minnis and deleted all traces that the top contrails scientist in the world had tried to talk sense to him, and Carnicom hasn't changed his website to reflect what even he himself found out in August 2000, twelve years ago, which is that there is a difference between ordinary "relative humidity" and "relative humidity with respect to ice".
 
The Carnicom Institute has released a new video edit of Aerosol Crimes explaining contrail formation. Not sure if these points have been addressed before.

The narrator repeatedly states (incorrectly) that contrails form easily in low humidity clean air... at and around the 4:30 mark.

 
"based on entirely different natural laws" - that's a rather stunning misunderstanding there.
 
I wonder where they got that nonsense.

My thought exactly. Maybe he's misunderstanding saturation of cold and warm air? Where a cold parcel of air can be saturated with less moisture than a warm parcel. Therefore cold air is drier, hence contrails form in dry air. Hard to tell since he doesn't explain his "science".
 
Carnicom has always misunderstood physics. Look at the OP to see several of his misconceptions and mistakes.
 
Contrails "need clean, dry air..."? I wonder where they got that nonsense.
Even I disagree with that . Being in a high humidity state with lots of persistent contrails . Seems to be quite the opposite ?
 
2.The conditions under consideration show that the ice crystals
within a contrail can warm to the melting point and subsequently melt
with the heat provided by solar radiation.

All through the vid they talk about contrails being "water vapor", but here they say they are ice crystals, as if the two are interchangeable.

PS: How do they image that the ice would "warm to the melting point" in the same environment which caused the freezing in the first place?
 
The whole new vid consists of them making some false assumptions, adding up to: "They can't be contrails", and then building a mountain of spurious stuff on top of that.
 
This is quite something to see. If the laws of science and aerodynamics do not conform to the beliefs of the chemtrail community, they will conveniently modify them to align with that they think they are seeing in the skies, when it comes to persistent contrails. I had one tell me the other day that airliners shut their engines off during approach and landing, hence the broken contrails.
 
I had one tell me the other day that airliners shut their engines off during approach and landing, hence the broken contrails.

Seriously?!?

It is ever increasingly difficult to counter the huge amount of misinformation that is developing RE: contrails, and the urban Legend of "chem"trails that is prevalent, today.
 
Seriously?!?

It is ever increasingly difficult to counter the huge amount of misinformation that is developing RE: contrails, and the urban Legend of "chem"trails that is prevalent, today.

I asked him how planes are able to execute missed approach procedures or taxi clear of the runways. The conversation ended very fast. Another posted on a fuel dump video, and tried to explain that since chemicals exist in fuel, it was in fact a chemtrail. One day they will decide what truly IS a chemtrail. It changes from day to day.
 
I had one tell me the other day that airliners shut their engines off during approach and landing, hence the broken contrails.

While they don't (obviously) shut off the engines, they do reduce thrust. This can theoretically cause a contrail to stop. Like with this (rather extreme case) AWACs


But of course the more important factor in approach is that planes get lower as they are getting ready to land.
 
While they don't (obviously) shut off the engines, they do reduce thrust. This can theoretically cause a contrail to stop. Like with this (rather extreme case) AWACs


But of course the more important factor in approach is that planes get lower as they are getting ready to land.


I do so agree, especially when we are executing an emergency separation from the tanker, the throttles are automatically cut to idle to increase the vertical separation. I think hearing someone claim that engines were physically shut off on approach and landing was quite humorous.
 
....the throttles are automatically cut to idle to increase the vertical separation.

In YOUR scenarios (aerial refueling procedures, in close proximity "formation" flying situations), then this makes perfect sense.

Problem is, for the "average" "chem"trail believer/enthusiast, they sometimes cannot discern the difference, or do not understand the reality of regularly scheduled airline operations, as compared to specific and (requiring EXTREME precision and utmost attention) air fueling OPs.

Just to clarify, for the casual reader:

Next time you might happen to be an airline passenger, know please that IF the engines were "shut off" completely, it would be rather noticeable, even to the layperson and non-aviation types.
 
Going back to the original bold claim by Carnicom:

http://www.carnicominstitute.org/articles/model1.htm

I think it is interesting to report his formula for the lifetime of a contrail (and of any cirrus, as already pointed out earlier) and compare it with the current models used to simulate the dynamics of contrails and cirrus.
"Thanks" to this bad physics personally I (re)learned some real physics which went forgotten during the years and I was able to debunk a nasty and arrogant chemtrailer in the process (see this Storify, sorry for the Italian).

According to Carnicom the following formula holds:

t [sec] = (m [kg] * Ht [J/kg] ) / P [W]

where t is the time to evaporation in seconds, m is the mass of an ice droplet, Ht is the heat of transformation of ice and P is the power in Watts coming from solar radiation. In turn,

Ht = dQ + heat of fusion = 4210 [J/kg/C] * (-T) [C] + 355,000 [J/kg]

therefore the impinging solar power would heat the ice droplet from the original temperature T up to 0 Celsius, when then evaporate with a specific heat of fusion. Plugging some ballpark figures for m and P one obtains lifetimes of few tens of seconds, at best.

Well, there are LOADS of reasons why this is an absurd model from a purely physical perspective.

First of all, the formula could be valid for an ice droplet in vacuum, since the environment plays no role at all, as already pointed out in earlier posts. But even in this case you have to consider P as a radiative balance between the incoming solar radiation, the incoming IR radiation from Earth and from the atmosphere, and the outgoing IR emission from the ice droplet at a certain temperature T (blackbody radiation). The absorption of incoming radiation,in turn, is a complicated affair since the droplet is quite irregular and one must make some assumptions to calculate the scattering. Intuitively, most of the incoming radiation is not absorbed, which gives a high albedo for the contrail and the cirrus. The net power could be either positive or negative, influencing the growth of droplets which are not in vacuum of course but in the atmosphere.

An example of such detailed calculations is given for example by GL Stephens, The Influence of Radiative Transfer on the Mass and Heat Budgets of Ice Crystals Failing in the Atmosphere, JAS 40 (1983), which shows cases of net heating or net cooling, affecting the growth rate (slowing or increasing, respectively, see figure 5, p.1736).

And then of course there is a feeling of weird stuff in the thermodynamics of Carnicom, I do not see why you need to go to 0 Celsius for ice-water equilibrium at standard atmospheric pressure?? Looking at the partial pressure vs temperature diagrams you could simply change temp with heating staying at the same pressure and hit the critical temperature for sublimation. But nevermind ...

Of course, as already pointed out in previous posts, there is a dynamical mass balance going on, which in full glory is described by many papers which aim at modeling the contrail and cirrus formation and evolution for detailed computer simulations. An example is given by VI Khvorostyanov and K Sassen, Cirrus Cloud Simulation Using Explicit Microphysics and Radiation, Part I and Part II, JAS 55 (1998). Just to give a feeling of all the physics involved, I quote here the abstract for Part I:

A mesoscale 2D/3D cloud model complex with explicit account for the water and ice cloud microphysics and radiative processes is described. The model has several versions suitable for the simulation of various cloud types, including, of particular concern in the current version, cirrus clouds. Model computations are based on the two kinetic equations for droplet and crystal size distribution functions, with division of droplet and crystal size spectra into 30 bins from 1 μm to 3.5 mm, and with account for the various mechanisms of cloud condensation and ice nuclei activation, condensation–deposition, and coalescence–accretion growth. These equations are solved along with supersaturation and radiative transfer equations for longwave and solar radiation. Simple yet accurate analytical expressions are presented for the scattering and absorption coefficients, and the single-scattering albedo. This allows detailed calculations of the optical and radiative characteristics of clouds (i.e., fluxes, divergence, and albedo) to be made at each grid point of the computational domain, thus yielding the spatial and time evolution of these properties along with the evolving cloud microstructure and phase state.
I think that Carnicom would have failed any Physics examination related to his Engineering degree (if any, really).
 
I've often seen people explain that, "..but the ice behind a contrail would melt very fast, because it is being warmed by the sun."
In reply, I point out that... "even at ground level, snow (ice) does not immediately melt when in sunlight if it is cold enough."

This is perhaps an easy way of explaining a similar "phenomenon", for people unwilling to tackle the math and physics.



Even in the arctic regions where there are very long days of sun....the snow is still frozen enough to become airborne all day, for days.
 
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