Mercury: GOVERNMENTS in Australia have been fiddling around the edges of climate change for well over a decade — years of window-dressing here, a small reform there, and an awful lot of talk. But last week, something changed. In the Green Paper released last Wednesday, Climate Change Minister Penny Wong outlined a scheme to make major emission source industries like coal power companies and oil refineries pay for each tonne of carbon released into the atmosphere, either directly or by users …