The campaign to re-elect the Rudd Government begins in July. It will be an incendiary month for shaping the direction of Australia's climate change policy.

On June 30, the Government's chief climate adviser, Professor Ross Garnaut, is scheduled to tender his draft report on the design of an emissions trading scheme and other climate-related strategies. Treasury modelling detailing the cost effects is due around the same time. Climate change will be top of the agenda at the meeting of the Group of Eight (G8) countries meeting in Japan a week later.

The Rudd Government will release its green paper on the design of an emissions trading system a couple of weeks after that. Climate Minister Penny Wong has been leading the Government's gradual distancing from the Garnaut review process. In July, the rhetoric will have to switch -- from consideration to action. One of the many poisoned chalices in the green paper is what the Government does about petrol. Including petrol and transport fuels in an emissions trading scheme will push prices up by somewhere in the vicinity of 10c a litre. Less if the scheme starts softly; more if it goes off the rails.

Australians share a national obsession with petrol prices, a politically charged issue greater than the sum of its parts. A 10c a litre price increase would cost a typical busy Australian motorist around $200 a year. To some, it will feel more like $2000.

The public responds to tangible environmental problems. Around 90 per cent of households recycle because they can see the problem and own the solution. The problems associated with plastic bags are elevated far above their real effect because they are so visible.

Climate change has always been a hard sell because it is relatively slow and invisible. But putting a price on greenhouse emissions will certainly get voters' attention, for all the wrong reasons.