New York Times: As world leaders struggle to hash out a new global climate deal by December, they face a hurdle perhaps more formidable than getting big polluters like the United States and China to reduce greenhouse gas emissions: how to pay for the new accord. The price tag for a new climate agreement will be a staggering $100 billion a year by 2020, many economists estimate; some put the cost at closer to $1 trillion. That money is needed to help fast-developing countries like India and Brazil …