Well, because this is roleplay and not a game, as so many people say, perhaps the GM/coGM can PM the people that would be most involved, and talk to them about the disaster or somesuch, so that it happens in a very story-line fashion, rather than a more game-breaking fashion that might happen- more like an electrical circuit blowing an entire energy network out, between the solar panels and the batteries, a mere day before a solar eclipse in a colonization game, rather than an Ion Storm in Tiberium Sun right when you started.
Aye. RPs aren't games, they are closer to books and stories. The fun comes from the co-operation and creativity rather than achieving a certain goal. When people run out of ideas, or no-one works with them, that's when they drop out. In a game, you can keep going by yourself, but in an RP you can't - a one-man RP is a story.