1) It is historic. John Kerry was right to use the phrase in his New York Times oped announcing the deal: for the first time a developing nation has agreed to eventually limit its emissions, which has become a necessity for advancing international climate negotiations.2) It isn't binding in any way. In effect President Obama is writing an IOU to be cashed by future presidents and Congresses (and Xi is doing the same for future Politburos). If they take the actions to meet the targets, then it's meaningful, but for now it's a paper promise. And since physics is uninterested in spin, all the hard work lies ahead.3) It is proof, if any more was needed, that renewable energy is ready to go. The Chinese say they'll be using clean sources to get 20 percent of their energy by 2030 -- which is not just possible, it should be easy. Which they know because they've revolutionized the production of solar energy, driving down the cost of panels by 90 percent or more in the last decade.Read More.Source: The Huffington Post/Bill McKibben