When it comes to the individual impact of countries on global warming I haven’t forgotten that the U.S. contributes about a fifth of CO2 emissions to the atmosphere. But looking fifty years out, the real growth concerns in GHGs revolve around India and China (U.S. energy consumption is actually leveling off in terms of growth after about sixty years of exponential increases, which should stabilize America’s contribution to GHG emissions somewhat).  Yesterday’s article in The New York Times highlights this very issue as it points out that air-conditioning sales are growing at 20 percent per year in India, which is a major problem for global warming since air conditioning gases like an HCFC coolant called 410a, have warming effects 2,100 times that of CO2. The industry has largely phased out CFCs, which harm the ozone layer, but there’s no regulation for air conditioning gases that cause global warming. One climate scientists has predicted that 27 percent of global warming will be attributable to air conditioning gases by 2050. With 55 percent of new air-conditioning units now sold in the Asia Pacific region, it’s worthwhile to consider if we need another international agreement, like the Montreal Protocol, to address not just the ozone layer, but the impact of air-conditioning gases on global warming.