Australia has bumped the U.S. out of the way and assumed the dubious distinction of the world’s worst per capita greenhouse gas polluter, according to an analysis of U.N. statistics by the Australia Institute, a left-leaning research group. On a per capita basis, Australia now emits 25 percent more carbon dioxide than the U.S. and 100 percent more than most European Union nations. The Australia Institute blamed the high emissions largely on coal-fired power and excessive land clearing, in which burning vegetation emits gases. Land-clearing rates in the state of Queensland have reached 1.8 million hectares a year, outpacing the worst rates in Brazil’s Amazon basin in 1990 and 1991. Land-clearing has accelerated in the region because landowners fear that penalties may be imposed for such clearing in the future.