A very good video and effort at transparency. You an read the information here and here.
Meteorolgist Chris Martz and Steve Milloy also weighed in on the issues.
Those are condensation trails.
These form when impurities in aircraft exhaust (typically tiny soot and sulfur compounds) act as cloud condensation nuclei (CCN) to form artificial cirriform clouds at high altitudes. These are not a new phenomenon, the pictures below show themโฆ https://t.co/pI00SN7IOhpic.twitter.com/6UK0l0VgE3
Cloud seeding does not "modify" the weather in any significant way. If there are rainclouds in an area, it can marginally increase rainfall on a localized basis. If cloud seeding was tremendously successful, this guy would have a better haircut. https://t.co/LMYkvZPx5Chttps://t.co/m1CWwgkyTQ