According to a United States Air Force contrail fact sheet, contrails, or condensation trails, are "streaks of condensed water vapor created in the air by an airplane or rocket at high altitudes." [ 4 ] These condensation trails are the result of normal emissions of water vapor from piston engines and jet engines at high altitudes in which the water vapor condenses into a visible cloud. Contrails are formed when hot humid air from the engines mixes with the colder surrounding air. The rate at which contrails dissipate is entirely dependent on weather conditions and altitude. If the atmosphere is near saturation, the contrail may exist for some time. Conversely, if the atmosphere is dry, the contrail will dissipate quickly. [ 4 ]
Exhaust gases and emissions
Chemtrails, coming from "chemical trails" in the same fashion that contrail comes from "condensation trail" is a term coined to suggest that contrails are formed by something other than a natural process of engine exhaust hitting the cold air in the atmosphere. Proponents of chemtrails characterize these chemical trails as streams that persist for hours, and by their criss-crossing, grid-like patterns, or parallel stripes which eventually blend to form large clouds. Proponents view the presence of visible color spectra in the streams, unusual concentrations of sky tracks in a single area, or lingering tracks left by unmarked or military airplanes flying in atypical altitudes or locations as markers of chemtrails. [ 1 ] [ 3 ] [ 8 ] [ 18 ] [ 19 ] [ 20 ]
A news station reported the results of tests on what they called chemtrails. "It seemed like some mornings it was just criss-crossing the whole sky. It was just like a giant checkerboard," said Bill Nichols, who reportedly noticed the "unusual clouds" begin as normal contrails from a jet engine, but unlike normal contrails, he claims, do not fade away. He then noticed "it would drop to the ground in a haze", the material collecting on the ground and in water he had sitting in bowls. KSLA News 12 sampled the water at a lab and initially reported a high level of barium, 6.8 parts per million, more than three times the toxic level set by the EPA. After contacting the Louisiana Department of Environmental Quality, the news station was told that these levels are very unusual, but proving the source "is a whole 'nother matter". KSLA discovered during their investigation that barium is a hallmark of other chemtrail testing. [ 21 ] However the KSLA reporter had misread the reading, which was actually 68 parts per billion, well within expected ranges, and the station retracted the story. [ 22 ] The phenomenon attracted the attention of a Los Angeles network affiliate, which aired a similar investigation called "Toxic Sky?" [ 23 ] Following suit, Phoenix News Reporter Pat McReynolds at CBS KPHO interviewed Geoengineering [ 24 ] investigators and concluded that chemtrails do not exist.
Contrail testing being carried out on an Airbus A340 and much older Boeing 707 [ 4 ]
Government agencies and experts on atmospheric phenomena deny the existence of chemtrails, asserting that the characteristics attributed to them are simply features of contrails responding differently in diverse conditions in terms of the sunlight, temperature, horizontal and vertical wind shear, and humidity levels present at the aircraft's altitude. [ 1 ] [ 3 ] [ 4 ] [ 8 ] [ 18 ] Experts explain that what appears as patterns such as grids formed by contrails result from increased air traffic traveling through the gridlike United States National Airspace System's north-south and east-west oriented flight lanes, and that it is difficult for observers to judge the differences in altitudes between these contrails from the ground. [ 4 ] The jointly published fact sheet produced by NASA, the EPA, the FAA, and NOAA in 2000 in response to alarms over chemtrails details the science of contrail formation, and outlines both the known and potential impacts contrails have on temperature and climate. [ 12 ] The USAF produced a fact sheet as well that described these contrail phenomena as observed and analyzed since at least 1953. It also rebutted chemtrail theories more directly by identifying the theories as a hoax and denying the existence of chemtrails. [ 3 ] [ 4 ]
Wingtip condensation trails
Patrick Minnis, an atmospheric scientist with NASA's Langley Research Center in Hampton, Virginia, is quoted in USA Today as saying that logic is not exactly a real selling point for most chemtrail proponents: "If you try to pin these people down and refute things, it's, 'Well, you're just part of the conspiracy'," he said. [ 1 ]
In 2001, United States CongressmanDennis Kucinich introduced legislation that would have permanently prohibited the basing of weapons in space, and he listed chemtrails as one of a number of exotic weapons that would be banned. [ 25 ] Proponents have asserted that because explicit reference to chemtrails was entered by Congressman Kucinich into the congressional record, this constitutes official government acknowledgment of their existence. [ 18 ] [ 26 ] Skeptics note that the bill in question also mentions "extraterrestrial weapons" and "environmental, climate, or tectonic weapons." [ 27 ] The bill received an unfavorable evaluation from the United States Department of Defense and died in committee, [ 28 ] with no mention of chemtrails appearing in the text of any of the three subsequent failed attempts by Kucinich to enact a Space Preservation Act.
From the wikipedia article. So far the evidence you have is that the contrails criss crossed, and were in flight paths that aren't used very often. Well that sounds like a solid case for massive global government conspiracy to poison the world's population for completely ambiguous reasons.