The Age of Stupid (2009)

This documentary is told from a future perspective of the last man living on earth, so it's a bit hyperbolic. It extrapolates our environmental damage to the planet to the point where all the polar ice caps have melted and all humanity (except one Brit) is lost to drought, storm, etc.

The man scans documentary footage of what is our present day of people trying to fight the trend towards obliteration. Some good stuff in terms of alternative energy, but discouraging in how very little traction their efforts make.

IMDB