Maybe following facts could be interesting for you:
In the end of June 2016 the CIA-Director John Brennan admits plans of Aerosol Spraying (Chemtrails).
I quote:

Another example is the array of technologies—often referred to collectively as geoengineering—that potentially could help reverse the warming effects of global climate change. One that has gained my personal attention is stratospheric aerosol injection, or SAI, a method of seeding the stratosphere with particles that can help reflect the sun’s heat, in much the same way that volcanic eruptions do.

I recommend you to look the source.

https://thefreethoughtproject.com/director-cia-stratospheric-aerosol-injection/