Flatlining

FOR years, it seemed like carbon-dioxide emissions rose relentlessly, whatever the world's level of economic activity and however much countries spent on no- or low-carbon energy. Now, though, that depressing fact may be changing. The International Energy Agency (IEA), made up mostly of energy-consuming rich countries, reckons worldwide emissions of carbon dioxide in 2014 were the same as in 2013. The only occasions CO2 emissions have actually fallen were in the early 1980s and 2008, both period...