Australian carbon tetrachloride emissions in a global context
Global (1978-2012) and Australian (1996-2011) carbon tetrachloride (CCl4) emissions are estimated from atmospheric observations of CCl4 using data from the Advanced Global Atmospheric Gases Experiment (AGAGE) global network, in particular from Cape Grim, Tasmania. Global and Australian emissions are in decline in response to Montreal Protocol restrictions on CCl4 production and consumption in the developed and developing world. However atmospheric data-derived emissions are significantly larger than ‘bottom-up’ estimates from direct and indirect CCl4 production, and CCl4 transportation and use. Australian CCl4 emissions are not due to these sources, and the identification of the origin of Australian emissions may provide a clue to the origin of some of these ‘missing’ global sources.