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Old 05-09-2008, 06:08 AM
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stompk stompk is offline
I work for God
Join Date: Jan 2008
Location: In the valley
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Default Contrails cannot form into clouds (proof!)

The combined moisture from the jet exhaust and the atmosphere will never be enough for the mixture to produce a cloud.
Appleman Chart - Student

Now I am going to debunk the scientists that claim the contrails forming into clouds and gray haze above your heads is normal, jet exhaust polluting our atmosphere.

And I'm going to do it by using a chart, the above website.

The chart is called the Appleman Chart. And it looks like this.

Background: Military planners have been interested in condensation trail (contrail) forecasts since World War II. Contrails can make any aircraft easy to locate by enemy forces, and no amount of modern stealth technology can hide an aircraft if it leaves a persistent contrail in its wake. In 1953, a scientist named H. Appleman published a chart that can be used to determine when a jet airplane would or would not produce a contrail. For many years, the US Air Force Global Weather Center used a similar chart to make contrail forecasts.
Now, the purpose of this thread is to show that PERSISTENT contrails forming into a cloud, is a myth.

Furthmore, I will show you the science. If you see a PERSISTENT contrail, then you can go to this website;
Atmospheric Soundings
and on the map, click on the city nearest you, and it will give you the
most recent sounding of the atmosphere.
atmosphere sounding. Satellite Meteorology. Methods for retrieval of atmospheric temperature and humidity profiles.
Now the chart will look like this
(current Denver, CO sounding)

384.0 7538 -33.5 -36.9 71 0.42 237 36 315.0 316.6 315.1
379.4 7620 -34.1 -37.8 69 0.39 235 35 315.3 316.7 315.4
362.8 7925 -36.5 -41.2 62 0.29 235 34 316.2 317.3 316.2
303.4 9144 -45.9 -54.7 36 0.08 235 40 319.5 319.8 319.5
300.0 9220 -46.5 -55.5 35 0.07 235 40 319.7 320.0 319.7
We're only interested in the first 5 columns.

1st column;
is the atmospheric pressure or hPa on the left of the Appleman Chart.

2nd column;
is the metric height.
Most commercial jets fly between 8 and 12 km (26,000 and 39,000 feet, or roughly 350 hPa to 200 hPa).[/ex]
30,000 ft = 9144 m. You can use this chart to do the conversion.

3rd column;
is temperature in c. It's roughly about the same as f at that temp.
If the atmosphere were warmer than the temperature indicated by the 100% line, a contrail could not form even if the relative humidity of the atmosphere were 100 percent
4th column;
is dewpoint. This is the point at which vapor will condense into water.

5th column;
Relative Humidity. Very important. According to NASA;
Both the temperature and humidity of the atmosphere help to determine whether a contrail can form. As the relative humidity in the atmosphere increases, the atmosphere is able to supply more moisture into the jet aircraft exhaust plume, and a contrail is more likely to form. The temperature of the atmosphere does not have to be as cold to form contrails at 60% relative humidity compared to 0% relative humidity.
Surprisingly, at cold temperatures ice clouds (including contrails) can form and persist at humidities lower than 100%. The red line (dash-double dot line) in the Appleman chart shows at what humidities contrails can persist (usually between 60% and 70% relative humidity). Thus, if the air is moist enough, and colder than (temperature profile is to the left of the red line), then the Appleman chart indicates that persistent contrails can form.
(bold added)

So, what it boils down to, is that on a clear day, it's very, very unlikely that a contrail would form, let alone persist.

And I've already shown that NASA said it is impossible for clouds to form from contrails.

Last but not least.

the USAF found that the forecasts using the Appleman method were correct about 60 to 80 percent of the time. Looking more closely at the data, they found that when no contrails were forecast, the forecast was correct 98 percent of the time! However, when contrails were forecast to occur, the forecast was correct only 25 to 35 percent of the time, and often failed to predict the occurrence of contrails.
Again, the Nasa link is
Appleman Chart - Student

And the satellite sounding site is;
Atmospheric Soundings


Last edited by stompk : 05-09-2008 at 06:11 AM.
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