Associated Press: A warming planet, deadlocked politicians, feuding scientists. The headlines about climate change are a source of worry and satisfaction to Ian McEwan. The British writer’s new novel, "Solar," brings the problem of global warming up against the fallibility of human nature, a conflict vividly illustrated by the failure of December’s Copenhagen conference and the scandal over leaked e-mails in which climate scientists bad-mouthed rivals and, skeptics say, distorted data to build their …