Australia's politically controversial carbon tax launched

Australia on Sunday imposed a price on carbon emissions but, even as it starts, the scheme's future is in doubt with conservative opposition vowing to repeal it and whipping up a scare campaign around it.

Australia on Sunday joins a growing number of nations to impose a price on carbon emissions across its $1.4 trillion economy in a bitterly contested reform that offers trading opportunities for banks and polluters but may cost the prime minister her job.