Hill: Bickering between the U.S. and China continue to mar global climate change talks after small progress on financially aiding efforts in developing nations was made this past week at a summit in China. Top U.S. climate change negotiator Todd Stern – speaking at the University of Michigan Law School Friday – said China is ignoring pledges made in a non-binding climate change accord in Copenhagen last December that was reached following a face-to-face meeting between President Obama and …