as seen from space: the fact that now the contrails persists for so
long is in itself a sign that something is not going well, but it's NOT
evidence they are "chemtrails."

A few things that should be considered when talking about so-called "chemtrails":

1) Obviously, there is some "spraying"
that goes on and it's not for the benefit of humanity. I've heard a few
stories from people about very low flying planes dispersing stuff that
lands all over everything or makes people sick. And I do mean LOW

2) Spraying that actually affects a
designated area beneath the sprayer (the plane in question) must be at a
fairly low altitude otherwise what is sprayed will not come down on the
area beneath the spraying. This is due to the fact that our atmosphere
has a number of layers and each layer has its own temperature and wind
speed and direction, and very often, things in one layer take a very
long time and distance to mix or mingle with other layers, IF they mix
at all. Usually, the wind speeds in the upper layers are such that
anything deposited there might only penetrate to lower, weather, layers,
after many thousands of miles of travel. It's a very nonlinear
situation and highly, impossibly, unpredictable.

3) So, if you are talking about chemical spraying that you can see above in the sky, that then falls on the area below it, you must be talking about low altitude spraying.

4) Therefore, trails that are very high in
the sky that have no hope of ever interacting with the ground below
them cannot properly be called "chemtrails" except, perhaps, if a
chemical is being sprayed that is supposed to affect the weather (and
even that is done fairly low). Cloud seeding is done by dispersing
elements such as dry ice crystals or silver iodide in the atmosphere
with an airplane or even ground based stations. Seeding clouds is
believed to promote condensation of water droplets, thus, rain.

5) Cloud seeding is usually done
TO clouds, it doesn't create them. Plus, it, too, must be done at a
fairly low altitude in order for the effects to affect the area below
the activity. Otherwise, the higher wind speeds in the upper layers
will carry the silver iodide away, disperse it, and the desired effect
will not be had. Here's a page about cloud seeding: http://www.sandylandwater.com/ops.htm

6) Small private planes fly at 12,000 feet maximum. Passenger airliners fly from 25,000 to 45,000 feet.
The Concorde super-sonic transport cruised at Mach 2 at 57,000 feet.
Miltary fighters get up to 80,000 feet, some specialty planes such as
The U2 spy plane and the SR-71 are thought to go as high as 120,000
feet. the x-15 has a ceiling of 354,000 feet.

7) From Wikipedia:

Cloud Types
© n/a

A chart showing the atmospheric levels and types of clouds that forms at those levels.

Cirrus clouds generally refer to atmospheric clouds that are
characterized by thin, wisp-like strands, often accompanied by tufts,
leading to their common (non-standard) name of mare's tail.[1] Sometimes
these clouds are so extensive that they are virtually indistinguishable
from one another, forming a sheet of cirrus called cirrostratus.
Sometimes convection at high altitudes produces another
form of cirrus called cirrocumulus, a pattern of small cloud tufts
which include droplets of freezed water. The term is also used for
certain interstellar clouds composed of sub-micrometre sized dust

Many cirrus clouds produce hair like filaments made of the heavier ice
crystals that precipitate from them. These "fall streaks", a form of
virga, often indicate the difference in the motion of air (wind
shear) between the upper part of the cirrus cloud and the air below it.
Sometimes the top of the cirrus cloud is moving rapidly above a slower
layer of air, or the streak is falling into a faster moving lower layer.
The directions of these winds can also vary

Cirrus clouds are formed when water vapor freezes into ice crystals at altitudes above 8000 meters (26,000 ft).[3] Due to the sparse moisture at a high altitude, they tend to be very thin.[1] At this altitude, aircraft leave condensation trails that can turn into cirrus clouds.[4]
This happens when hot exhaust, mostly water, freezes, leaving a visible
trail. Streaks may appear straight when wind shear is absent, giving
the clouds the appearance of a comma (cirrus uncinus), or tangle, an indication of high-level turbulence. The falling ice crystals evaporate before reaching the ground.

© Wikimedia Commons

A sky covered with cirrus clouds.

Cirrus clouds cover up to 30% of the Earth and have a net heating effect.
Cirrus clouds efficiently absorb outgoing infrared radiation (heat)
beneath them (greenhouse effect), while only marginally reflecting
incoming sunlight (albedo).[5]

A high number of cirrus clouds may be a sign of an approaching frontal system or upper air disturbance.
This usually signals a change in weather in the near future, usually
becoming increasingly stormy.[6] Cirrus clouds can also be the remnants of a thunderstorm. A large shield of cirrus and cirrostratus typically accompany the high altitude outflow of hurricanes or typhoons. Cirrus
clouds have also been observed developing after the persistent
formation of contrails from an aircraft. Increase in air traffic is a
possible cause of an increasing amount of cirrus clouds

8) Now, what is wrong with the picture presented above?

Answer: the altitude of cirrus clouds vs the altitude of many jetliners
that criss-cross the skies with trails which are obviously much lower
than the altitude designated for cirrus clouds.

YET the trails left by these aircraft ACT like cirrus clouds used to act at much higher altitudes.

Most logical (and scariest) conclusion: the cold layer of the upper
atmosphere has gotten lower and probably thicker and therefore, more
airplanes flying at lower altitudes are forming contrails in that icy
air which used to be the much higher domain of cirrus clouds.

Because, again, if you understand about the layers of the atmosphere,
temperatures, winds, etc, then you will realize that what is happening
is NOT spraying of the human population or even intentional weather
manipulation, it is the EVIDENCE that our planetary atmosphere has
changed dramatically in the past ten years or so. More like 20 because
that was when I began noticing the changes in cloud formation.

9) Also notice that the trails left by
planes at much LOWER altitudes, generally dissipate quickly. What is
bad news is that they leave ANY trail at all at those altitudes! (And
knowing how layers that form cirrus clouds function from the above, you
can pretty well understand that they are not spraying stuff on the
ground below.) But certainly, there CAN be the natural formation of
cirrus clouds by plane exhaust or fuel dumping AND low level spraying of
"stuff" at the same time. I would suggest that such cases are "cover
up" the same way the endless "gray alien abductions" are a cover-up for
what aliens are REALLY doing on this planet.

For example, this very stupid video that is claimed to be "cloud seeding":