Climate Control Decades

FILE - In this Jan. 19, 2012 file photo, smoke rises in this time exposure image from the stacks of the La Cygne Generating Station coal-fired power plant in La Cygne, Kan. Carbon dioxide pollution has increased steadily, by 60 percent, from 1992 to 2013. In 1992, the world spewed 24.9 billion tons of carbon dioxide, now it is 39.8 billion, according to scientists at the Global Carbon Project international consortium. (AP Photo/Charlie Riedel, File)