Reuters: Climate campaigner Al Gore urged world policymakers on Thursday to change laws "not just light bulbs" in tackling global warming, and a U.N. official said world market turmoil must not be allowed to delay action. An annual meeting of world political and business leaders in Davos, Switzerland, this year has scheduled a record number of sessions and workshops on global warming. But a sharp downturn on markets and fears of recession have dominated discussion. "If we get distracted …