Reuters: Trade in controversial carbon rights under the Kyoto Protocol after 2012 could undermine emissions targets agreed under a new global climate pact, the European Union environment commissioner said on Tuesday. Under the Kyoto treaty, which expires in 2012, nations that are comfortably below their greenhouse gas emissions targets can sell the difference in the form of rights called Assigned Amount Units (AAUs) to countries struggling to meet their own targets. “If we have this …