Lesley Stahl of '60 Minutes' travels to Greenland to investigate the effects of global warming in the Arctic. Down south, Ian Somerhalder travels to North Carolina to listen in on both sides of the evangelical community's debate over climate change and finds himself caught in the middle of not only a religious debate, but a familial one: the father is a megachurch preacher who doesn't believe in climate change; the daughter is an activist trying to shut down the local coal-fired power plant.