PBS Documentary - Earth Emergency
This film introduces the mechanics of several major feedback loops contributing to climate change. This missing piece of the climate puzzle is pushing climate to a tipping point. It's harrowing, but is well worth the 52 minutes of your time. It will leave the viewer better able to discuss why global climate action is urgent.
It's available for $4 on Amazon Prime Video, and free for PBS members at https://www.pbs.org/search/?q=earth+emergency.