JAKE TAPPER: So that's- that’s the good news, the good vision, but what happens if the world doesn't act? What's the worst-case scenario? FORMER VICE PRESIDENT AL GORE: Well, the scientist who warned us of these mega-storms and the floods and mud slides and droughts and the ice melting and the sea level rising and the storms getting stronger and the tropical diseases, and climate and migrants crossing international borders in large numbers, they were dead right when they warned us about this and so we need to pay more attention to them now. Here’s one thing they say: if we don't take action, there could be as many as 1 billion climate refugees crossing international borders in the next several decades. Well, a few million has contributed to this wave of populist authoritarianism and dictatorships and so forth. Uh, what would a billion do? We can’t do this. We could lose our capacity for self-governance.
