In his book "Plan B 3.0: Mobilizing to Save Civilization", Lester R. Brown outlined the problematic situation we are in and proposes a set of measures as "Plan B.".
While this is not new in the list of issues and solutions, it shows some interesting numbers.
You can get a free PowerPoint slideshow summarizing his book here.
"Saving civilization is not a spectator sport."
" The choice is ours. It will be made by our generation, but it will affect life on earth for all generations to come."