Reuters: Compulsory caps on carbon emissions by big firms are not a proven tool to fight climate change, despite their mounting popularity among other rich nations, an official at Japan’s top business lobby said on Friday. The country’s industry has used a voluntary scheme to keep emissions below levels of three decades ago and critics should look at results rather than fixating on methods, said Masami Hasegawa at the Japan Business Federation (Keidanren). He rejected the warning of a …