Dr. Greer has commented that he does not agree with much of “chemtrail” lore, but he does say the ETs are most concerned about the collapse of the biosphere. These reports from Dane Wigington (of Shasta County, California) are the best info I have seen on chemtrails (a.k.a. geo-engineering or climate engineering) …. and their relevance to the collapse of the environment. Mr. Wigington is as erudite on this topic as Dr. Greer is on ETs.
Dane Wigington on chemtrails (Jan 2014): https://www.youtube.com/watch?v=5yZhh2leRJA#t=1441
Dane Wigington on chemtrails (July 2014): https://www.youtube.com/watch?v=OsYG5emdZp8#t=14
Dane Wigington is a member of this organization: http://www.geoengineeringwatch.org/
Anonymous testimony from a pilot in the US Airforce (… interesting): https://www.youtube.com/watch?v=5HqqnrQWC5U