Guardian: It is easy to feel powerless in the face of global warming. Even the phrase itself is impersonal, while the science behind it is dense and its long-term implications still contentious. Now the Intergovernmental Panel on Climate Change, which is meeting in Berlin this weekend to present its draft proposals for mitigating the impact of warming, has woken up to the need to get both more specific and more positive. Big targets on emission reductions still matter, but there are lots of smaller ones too,...