NASA Appleman Chart - Real contrail science

reply to post by sandwiches


Ok forget that then

Now are you going to answer my previous questions about the winds?

Originally posted by OzWeatherman
reply to post by sandwiches

Now are you going to answer my previous questions about the winds?

So demanding. This is addressed in the OP.

To me, winds do not adequately explain stationary trails with multiple breaks - sometimes it appears as though one of two trails will sputter out. I also do not find your theory explains trails starting and stopping, short "dashes" and "puffs" of chemtrails. One would be hard pressed to prove this can in fact happen with natural atmospheric variations.

reply to post by sandwiches


Hey sandwiches, good thread.

Have you read some of these peer reviewed papers?

A New Formulation for the Critical Temperature for Contrail Formation

Abstract
A new formulation of the equations describing the conditions necessary for aircraft exhaust contrail formation is derived from the fundamental necessary condition. First, the original solution of Appleman is derived from the necessary condition to illustrate the continuity of the new formulation. Then the new formulation offers an analytic solution for the critical temperature Tc expressed in terms of water vapor mixing ratio and atmospheric pressure, rather than in terms of relative humidity and pressure, thus avoiding potential forecast errors associated with the temperature sensitivity inherent in relative humidity. A variety of results is presented, including a comparison with the seminal results of Appleman, a comparison of the sensitivity of Tc to perturbations in relative humidity versus perturbations in mixing ratio, and some typical results for actual atmospheric conditions. The clear superiority of a formulation based on mixing ratio rather than relative humidity is seen in the reduced sensitivity of c, to errors or uncertainties in the input atmospheric variables.

Source

An Empirical Model to Predict Widespread Occurrences of Contrails

Abstract
The increases in total cloud amount documented for large regions during the latter half of the twentieth century have focused attention on the potential contribution from jet condensation trails (contrails). The environmental conditions that favor contrail formation and persistence are not well understood primarily due to the limited number of empirical studies. This study presents an empirical model to predict widespread occurrences of contrails (outbreaks), which was developed from a combination of rawinsonde temperature and GOES water vapor information. Environments containing persisting contrails were first identified on Defense Meteorological Satellite Program satellite imagery for the United States for January and April 1987 and then analyzed in more detail using Advanced Very High Resolution Radiometer (AVHRR) satellite digital data. Adjacent clear and cloudy environments not containing contrails were identified to compare with the conditions favorable for contrail persistence. For this purpose, a predictive logistic model was developed through multiple regression analysis. The model performance was evaluated through goodness-of-fit methods and found to be statistically significant across a range of atmospheric conditions. To further evaluate the model and to demonstrate its application on a real-time basis, predictions of the probability of persisting contrails were made for a case day. Comparisons of the predictions to satellite observations of the existing conditions (using AVHRR data) demonstrate good model performance and suggest the utility of this approach for predicting persisting contrail occurrence. Implementation of this model should allow climate researchers to better quantify the influence of contrails on surface climate and natural cloud formation.

Source

Statistical Contrail Forecasting

Abstract
The current operational Air Force Weather Agency condensation trail (contrail) forecast technique is based on the Appleman algorithm, developed in the 1950s, with minor modifications. The Appleman algorithm requires accurate measurements or forecasts of ambient flight-level temperature, relative humidity, and pressure, as well as the amount of heat and water vapor added by an aircraft to its exhaust to determine accurately the critical temperature for contrail formation. Several factors contribute to the relatively poor contrail forecasts produced by the Air Force Weather Agency contrail forecast technique, including insufficiently accurate atmospheric measurements and numerical weather prediction forecasts of temperature and humidity at flight level, as well as some of the procedures used in the Air Force Weather Agency’s implementation of the Appleman algorithm.
The Contrail Field Program was conducted in eastern Massachusetts during a 10-day period in September 1995. Radiosonde data and aircraft observations were collected from a five-station network. Radiosondes were launched every 3 h, and aircraft observations included aircraft type, aircraft speed, aircraft altitude, and whether the aircraft produced a contrail. This dataset of nearly coincident (in time and space) radiosonde and aircraft observations was used to develop a new statistical regression contrail prediction model and to compare the results of the new statistical model with nowcasts produced by the Schrader algorithm, which is very similar to the Air Force Weather Agency contrail prediction technique, known as ‘‘JETRAX.’’ The Statistical Contrail Forecast Model makes use of logistic regression techniques to relate the presence or absence of observed contrails with nearly coincident radiosonde measurements. The statistical model produced a correct diagnosis of contrail occurrence or nonoccurrence for 85% of the observations, as compared with 58% correct for the Schrader technique, for this particular dataset.

Source

As you can see, the Appleman chart, as good as it is for day to day contrail forecasting, isn't much chop for highly accurate and specific forecasts.

Thoughts?



[edit on 30/5/10 by Chadwickus]

reply to post by Chadwickus

Thoughts?

As in the OP, I mostly concern myself with the 98% accurate prediction of NO contrails by the appleman chart.

This has been sufficient (for me) in showing glaring contradictions between what we should see and what we do see.

[edit on 2010-5-30 by sandwiches]

Originally posted by sandwiches

Originally posted by OzWeatherman
reply to post by sandwiches

Now are you going to answer my previous questions about the winds?

So demanding.

This is addressed in the OP.

To me, winds do not adequately explain stationary trails with multiple breaks - sometimes it appears as though one of two trails will sputter out. I also do not find your theory explains trails starting and stopping, short "dashes" and "puffs" of chemtrails. One would be hard pressed to prove this can in fact happen with natural atmospheric variations.

Well, thats because its not winds that do it. The atmopshere is not at a constant. In other words, there can be dry pockets of air around, sometimes in between clouds. The amount of water in the exhaust is pretty constant, but the amount of moisture in the air is not. The humidity varies with altitude, and a layer of low humidity can be sandwiched between two layers of high humidity. As a plane climbs or descends through this layer, then the trail will only form in the areas of high humidity, and so look like it was “switched off” in the area of low humidity. You can also get gravity waves to which force dry air into moist areas, or convective uplift of dry surface air, causing a dry vertical column

You can also get it when there's inversion layers. Sometimes you can see th plane climb from moist air into an inversion layer, and the trail appears to stop, as there is very little humidity to support a contrail forming in that dry air.

Basic meteorology

The wind had to do with releasing something up there, and why it wouldnt reach the ground directly below where it was releassed...but forget about that now

reply to post by OzWeatherman

Perhaps wind and pockets would be a factor in conditions near-conducive to persistent contrails. To avoid error, I implore you and others to look for lingering trails in conditions completely non-conducive to any contrails at all, let alone persistent ones.

Thanks

firstly thanks for all of that guys, but I have two things i dont get it:

Are there or are there not Chemtrails?

Are ChadWickus and Sandwiches the same person or not?


Thanks and keep the good work... Peace

reply to post by Refluir


Say what?!

That's a big fat no!

Originally posted by Refluir
firstly thanks for all of that guys, but I have two things i dont get it:

Are there or are there not Chemtrails?

Are ChadWickus and Sandwiches the same person or not?


Thanks and keep the good work... Peace

Not.
No.

Originally posted by Refluir
firstly thanks for all of that guys, but I have two things i dont get it:

Are there or are there not Chemtrails?

Are ChadWickus and Sandwiches the same person or not?


Thanks and keep the good work... Peace

Nobody is sure if there are Chemtrails or not. People like chad and oz, say that there is no such thing as chemtrails. Their main argument is that Contrails exist naturally. Of course they do, doesn't mean chemtrails don't exist.

Then there are other people, who may not be sure if chemtrails exist or not, but they believe that it is more dangerous to ignore chemtrails, than to do research on them.

No, chad and Sandwiches aren't the same person.


[edit on 31/5/10 by GobbledokTChipeater]

Originally posted by OzWeatherman

...why it wouldnt reach the ground directly below where it was releassed...

I have said this in the other thread...

Perhaps whatever is being sprayed is intended for the upper atmosphere. Therefore it doesn't matter if it reaches the ground "directly below where it was releassed (sic)..."

Your insistence on this (minor) point shows that you can't think outside of the box.

Originally posted by GobbledokTChipeater
Perhaps whatever is being sprayed is intended for the upper atmosphere. Therefore it doesn't matter if it reaches the ground "directly below where it was releassed (sic)..."

I've seen silent low-flying planes leave "light" trails (also notice both are dual nozzle trails) and then weird grid-like clouds appear out of nowhere... I think sometimes they spray "wherever" then gather particles with energy. Question is.. who are they? Russians? NWO? ETs?

Then there's the usual parallel lines on warm, dry days...

Look like 30,000 ft to you? It definitely wasn't -35C that low.

[edit on 2010-5-31 by sandwiches]

reply to post by sandwiches


Interesting. So when someone says "but it's sprayed so high it would never reach it's intended target on the ground" as an argument against chemtrails, I can clearly tell they are misinformed or have only ever seen a proper contrail


Edit: Certainly looks lower than I have ever seen "contrails" form before. I have never in my life seen "persistent contrails", as shown in your vid. Every contrail I have seen tapers off a good few plane lengths behind the plane.

[edit on 31/5/10 by GobbledokTChipeater]

reply to post by GobbledokTChipeater

I don't think all particles are necessarily designed to "land" on a specific target.

There's an article called nano-chemtrails by Will Thomas.

Some particles are so small they can linger for days, months or even years.

Every contrail I have seen tapers off a good few plane lengths behind the plane.

Take a look at other planes on the same day. If it's warm and dry you might find they don't leave any contrails at all. That means on such days even these "light" trails are suspect chemtrails, even though they don't "persist" longer than 30s or so.

[edit on 2010-5-31 by sandwiches]

Originally posted by GobbledokTChipeater
reply to post by sandwiches

I have never in my life seen "persistent contrails", as shown in your vid.

Watch the skies.. especially near sunrise and sunset on days when you can see some blue. In my experience the trails never stop for more than 2-3 days. They mostly follow the sun, but sometimes they're everywhere...

You should check out the documentaries Don't Talk About the Weather and Aerosol Crimes. Also YouTube and Google images for "chemtrails"... I also have many more vids of my own from the last several months.

[edit on 2010-5-31 by sandwiches]

reply to post by sandwiches


Thankyou for the links. Very interesting I'll have a proper look tomorrow.

Also. Great thread. It makes it hard to say it's a normal contrail if the Appleman Chart predicts with a 98% certainty that contrails will not form.

Hmm this thread is trying to be scientific about chemtrails by using the Appleman chart.

So why are the three peer reviewed papers I posted being ignored??

I hope it's not because they take the Appleman chart and improve on it, thus debunking the OP's pseudo-scientific attempt at using it to prove chemtrails.

reply to post by Chadwickus

Perhaps you failed to see the response I posted immediately following your post.

There is nothing wrong with the appleman chart's 98% accurate prediction of no contrails.

I recommend using this instead of making it unnecessarily more complicated.

Thanks

Originally posted by sandwiches
Perhaps you failed to see the response I posted immediately following your post.

I saw it, it was a response of someone who shrugged it off completely.

There is nothing wrong with the appleman chart's 98% accurate prediction of no contrails.

These three papers disagree.

I recommend using this instead of making it unnecessarily more complicated.

Thanks

I recommend that you review these papers, if you're truly embracing science, then these papers are the bees knees of contrail science.

reply to post by Chadwickus

Feel free to support your claims.