The Senate has voted to ratify a global climate treaty that will phase down the use and production of hydrofluorocarbons, or HFCs, the climate-warming chemicals widely used in air conditioning and refrigeration. The Senate voted 69-27 on Wednesday to move forward the 2016 Kigali Amendment, an amendment to the 1987 Montreal Protocol climate treaty that dramatically curbs the use of HFCs, which are thousands of times more potent than carbon dioxide at heating up the Earth. Forty-eight Democrats and 21 Republicans voted in favor; four members of the Senate did not vote. “This is a win-win in our fight against...