Chemtrails are plausible, but hard to certify. You can open an Appleman Chart and also open atmospheric soundings published daily from the University of Wyoming and witness occasionally in person long-lasting and expanding haze created by airplanes. This phenomenon should be incredibly rare, but its a very regular occurrence despite the conditions not being met. I have witnessed this first hand.  You combine that with actual experiments and programs run by global governments to control the weather (Like KSA cloud seeding to create rain).  Chemtrails are not a crazy conspiracy. They are well into plausible territory. Especially since articles produced recently basically say that our own government wants to run this type of experiment in the USA.  Try it yourself sometime: http://weather.uwyo.edu/upperair/sounding.html https://physics.stackexchange.com/questions/380882/why-can-a-contrail-only-form-below-40-degree-celsius