Which countries have emitted the most greenhouse gases? The quick answer is, "It depends." A more definitive response is tougher than you may expect. Many factors inform the answer.
Negotiators and stakeholders headed to Bonn, Germany, for next week’s UN climate summit continue to confront a range of questions surrounding one essential query: How do we meet the imperative to lower greenhouse gas emissions now — quickly — to minimize the most severe impacts of climate change?