This is to answer chemtrail debunker Jay Renolds.
"First, one should be aware that none of these claims can be considered either a hypothesis or a theory, they all fall in the realm of speculation."
Some scientific literature do exist to support some of the claim.
"-Poisonous Substance in Fuel"
One should remember that every jet exhaust produce poisonous substance for human. The difference is in the level. So it is not too important if it contain dangerous substance or not, jet engine output will still be poisonous.
"-Weather Modification & -Solar Radiation Mitigation"
Science literature exist that explain how normal contrails and cirrus cloud it produce have bad effects to the environment. The conclusion is contrails and contrail cirrus modify weather. They increase regional temperature significantly.
Also scientific reference exist about how to induce or to prevent rain with cloud seeding method. It is a known idea and had been experimented. So, weather modification is not an impossible option.
"In my words, "Contrails don't cause weather, weather causes contrails.""
Above is a wrong conclusion, without aeroplane, there would be no contrails. Contrails is man made, weather can not cause contrails. Weather is only a supporting factor, but this may be wrong too because trails also observed on unfavorable weather. Even some scientist puzzled by the existance of trails that last for hours in an impossible condition.
See my other post for reference.
"Normal persistent contrails can and do provide cirrus clouds which can block some sunlight and UV radiation, but their global coverage is miniscule."
Trails is severe problem. Many people report with photos and videos showing how the sky to become fully covered with clouds or trails dense enough to block the sun. And blocking sun for days can have severe health effects.
"-Global Warming Mitigation"
Some scientific reference mention how most scientist agree that contrails and contrail cirrus promote regional warming. And also this is concluded on observation that include only a handfull of trails in the sky. Should the observation is done during fully covered sky with trails, scientist would conclude that they promote global warming significantly too.
Even ordinary contrails have significant contribution to global warming. It is not important to differentiate chemtrail and contrails. None is harmless.
Proof exists that show sky is completely covered by trails and cloud created by the trails. They can last for days and even weeks. Refuting te possibility of hiding activity is also speculation.
Trails currently unregulated. Trails can be regulated by monitoring each plane activity and rerouting flight. It is possible to do and do not compromise the safety of flight.
Seeing how tight the government regulate ground vehicle, the none existance regulation on contrails looks like a miracle. Police should chase after the plane that produce trails like how they chase us when our car produce smoke.