I assume you mean this site?

http://asd-www.larc.nasa.gov/GLOBE/science.html

Did you also have to look at the Air Force’s “Contrail Facts”? It does a very good just of explaining many contrail myths.

http://www.af.mil/shared/media/document/AFD-051013-001.pdf

Finally got around to poking through NASA’a “contrail science” education site.
Not only do they present DIFFERENT info than you do but also use very questionable terminology
which doesnt seem to align with the position you state above…”that there are no ‘chemtrails’”.

What is your video about then? Where you stand around looking at a sky full con contrails? I thought you said they are different?

Skywriting is quite different from contrails. The planes are usually much smaller. The trail dissipates at a very consistent rate. They do not fly from horizon to horizon. The trail does not spread out into a layer of cirrus. The trail is often seen to be below cumulus clouds. It often creates letter or symbols.

Now, if you are asking if it’s possible to create a trail that looks very like a contrail, then yes. But you’ve been saying all along that the trails are very different.

So which is it?

In other words, YOU COULDNT TELL THE DIFFERENCE!!!
YOU STATE that “SKY WRITING” is done by mixing a “FINE OIL” in with the exhaust!!!
And this is done at MUCH lower altitudes where the air is usually too warm and not humid enough
to form contrails!

Gotcha.
So if i show you a clip of “chemtrails” with a “rapidly dissapating contrail” there can by more explanations than just
differing altitude.
This means that if there WERE chemtrails(proven or disproven), they could be dispersed at any height and not be distinguished from a so called “normal” contrail.

So how do you know they are not persistent contrails?

I understand completely based on relative humidity and temperature how a layer of ice crystals can be formed
which one might call a cloud.

I also understand completely that there have been, and are plenty of ongoing weather modification/ionospheric/atmospheric experiments…also biological warfare and tests on civilian populations.
Because I personally find very peculiar things as I have begun to more carefully watch the skies, this is the reason
why I happen to believe that some of what you call “persistant contrails” are composed of something, or administered in a manner that is quite deliberate and undisclosed for a reason.
Beyond that I am an environmentalist and naturalist. I take it personally.

That is all.

By CTYForganization:
“So you admit you have no fucking clue how aircraft “persistant contrails” affect the environment? weather?
What a jackass. You dont actually have to be a rocket scientist to figure this out.”

If you’re done making personal attacks, maybe you’d like to discuss the actual topic at hand?

What are your thoughts on persisting ground level contrails?

Do these examples help you understand how persistent contrails are formed and can spread out?

As someone who lives in a northern state that sees -20 to -30 fahrenheit temperatures every winter, I see scenes like the pictures above all the time (although I haven’t checked out the airport when it gets that cold…I should do that).

The exhaust from cars, factories and houses all form a sort of glittery icecrystal fog that isn’t easily explained to someone who has no concept of what “cold” really is. And when the sun hits it WOW is it ever bright, Sunrises/Sunsets are so beautiful on mornings like those.

What is NOT entirely clear is what the net heating or cooling effect is. Is the heating greater than the warming? Are there secondary effects? See:

http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch2s2-6-2.html

Aircraft produce persistent contrails in the upper troposphere in ice-supersaturated air masses (IPCC, 1999). Contrails are thin cirrus clouds, which reflect solar radiation and trap outgoing longwave radiation. The latter effect is expected to dominate for thin cirrus (Hartmann et al., 1992; Meerkötter et al., 1999), thereby resulting in a net positive RF value for contrails.

i.e., they think it’s a net warming effect. Wikipedia agrees:

http://en.wikipedia.org/wiki/Contrail#Vapour_trails_or_contrails_and_climate

Vapour trails or contrails, by affecting the Earth’s radiation balance, act as a radiative forcing. Studies have found that vapour trails or contrails trap outgoing longwave radiation emitted by the Earth and atmosphere (positive radiative forcing) at a greater rate than they reflect incoming solar radiation (negative radiative forcing). Therefore, the overall net effect of contrails is positive, i.e. a warming.[3] However, the effect varies daily and annually, and overall the magnitude of the forcing is not well known: globally (for 1992 air traffic conditions), values range from 3.5 mW/m² to 17 mW/m². Other studies have determined that night flights are mostly responsible for the warming effect: while accounting for only 25% of daily air traffic, they contribute 60 to 80% of contrail radiative forcing. Similarly, winter flights account for only 22% of annual air traffic, but contribute half of the annual mean radiative forcing.[4]

Uncinus
It’s not actually entirely clear what they do – heat or cool. Have a look at this:
http://www.pbs.org/wgbh/nova/sun/contrail.html

So you admit you have no fucking clue how aircraft “persistant contrails” affect the environment? weather?
What a jackass. You dont actually have to be a rocket scientist to figure this out.