Derb, of course Al Gore blames Lake Chad’s disappearence on global warming. As my colleague Marlo Lewis discovered (pages 8-9 of the PDF), Scientists who’ve studied Lake Chad say differently. Marlo concludes

In short, the Lake Chad disaster was one part local climate variation, one part local tragedy of the commons. Yet Gore blames the USA. He calls global warming a “moral issue,” but for him it is actually a moralizing issue. Global warming allows Gore to discover moral agency and guilt in the workings of inanimate nature. It allows him to “blame America first” for misfortunes around the world that may be entirely due to local actions and/or climatic factors beyond human control.

As for the Aral Sea, although he mentions it in his global warming movie, even Gore admits that its destruction is due to the Soviet Union diverting the Anu Darya and Syr Darya rivers away from it.