Reuters: The world must avoid a “cheap and dirty” fix for the economy that could undermine the fight against global warming, the U.N.’s top climate official said on Sunday. Yvo de Boer said the world risked a second financial crisis if governments reacted to economic slowdown by building cheap, high-polluting coal-fired power plants that might then have to be scrapped as climate impacts hit. “What concerns me most is that the financial crisis will lead to a second set of bad investment …