Nation: I haven't returned to Mount Rainier to see just how much further that glacier has receded in the last few years, but recently I went on a search to find out just how bad it might turn out to be. I discovered a set of perfectly serious scientists--not the majority of all climate scientists by any means, but thoughtful outliers--who suggest that it isn't just really, really bad; it's catastrophic. Some of them even think that, if the record ongoing releases of carbon dioxide into the atmosphere, thanks...