Reuters: China’s goals to slow greenhouse gas growth will be tough and costly, the nation’s top climate change official said on Wednesday, presenting an absolute cap and major carbon market in the world’s top emitter as distant plans. China’s key policy for fighting global warming is to reduce its “carbon intensity” — the amount of the main greenhouse gas, carbon dioxide, emitted for each dollar of economic activity — by 40-45 percent by 2020 compared to the 2005 level. That domestic …