(Reuters) – U.N. Secretary-General Ban Ki-moon on Friday appointed former New York City Mayor Michael Bloomberg as his special envoy for cities and climate change, in a bid to build momentum ahead of a planned U.N. summit meeting in September. Ban said Bloomberg will assist him in “consultations with mayors and related key stakeholders, in order to raise political will and mobilize action among cities as part of his long-term strategy to advance efforts on […]