Reuters: Targets and trust. These are at the heart of a tougher new global climate pact possibly just weeks away. The bigger the pledged emissions cuts or reductions in growth in carbon dioxide pollution, the greater the need to prove nations meet those targets and curb the pace of climate change. And proof of emissions reductions over time will help unlock billions of dollars in climate funds for poor nations. The problem, though, is that it is not yet possible to independently …