The ALP is campaigning pretty hard on environmental issues at the moment, and will probably continue to do so throughout the campaign. This is not surprising because the Coalition government has publicly rejected what was widely regarded as the most significant treaty in international environmental management: the Kyoto Protocol. Everyone knows that the Protocol exists, but few people are aware of the content.
Of course, the government's reasons are that the protocol doesn't include controls for developing nations such as China and India. As someone who's been to the industrial cities of China I can tell you that if there was a nation that required some regulation, it is China. So I agree with the Coalition hesitancy in that regard. The other major reason for not signing is that it will cost Australian jobs if we are to comply with the protocol. This is something I don't agree with.
The Coalition campaigns on its perceived strengths of economic management so the ALP will campaign on the Coalition's perceived weaknesses of environmental management. It's all about perception. In comparison to the Coalition, the ALP looks like caring and green citizens - even though they aren't nearly as green as the Greens.
(Note also that the ALP is pushing the undercurrent that the Coalition is only riding on low unemployment and a booming economy because of the booming global economy - but they won't push it too hard until they need it as a safety net for when the global economy slows.)
After all is said and done, the ALP is currently ahead on the environmental issues in the minds of the voters, but whether that will turn into governmental action remains to be seen. Unlike the previous election that was won on the fear of rising interest rates, this one will be won by the voters perceiving a strength in one side when there is really only a greater weakness in the other side.
Hooray for relativity in perception.