Agence France-Presse: The city of Tokyo on Thursday launched Asia’s first scheme to trade carbon credits, aiming to lead Japan in the battle against greenhouse gas emissions blamed for climate change. The mega-city of 13 million mandated that the 1,400 top-polluting factories and office buildings reduce emissions, with the aim of slashing Tokyo’s total output of carbon dioxide by 25 percent from 2000 levels by 2020. “We want to be a model for the Japanese government,” Yuki Arata, the director for …