As the United States lags on climate legislation, China is poised to join the European Union in claiming "front-runner" status among nations battling climate change, the UN climate chief said Monday. Yvo de Boer said in an Associated Press interview that China is leaping ahead of the United States with domestic plans for more energy efficiency, renewable sources of power, cuts in vehicle pollution and closures of dirty plants. The development marks a dramatic turnabout. The United (…)