Economics is called the dismal science for good reason.
I always try to separate the science of climate change from the economics which basically means that I am not convinced by the argument for a Carbon tax. First of we Gillard is proposing a tax on the production side rather than a tax on consumption side. This immediately puts Australian industry at a disadvantage to goods imported from countries without a Carbon tax. A tax on the consumption side would tax imports and domestic produced goods equally. But Gillard doesn't want to do that because it is harder to implement and will put prices up immediately in a way that can't be hidden.
Personally I think we first need to eliminate all forms of subsidy on high carbon producing industries. Lets get rid of all the special deals to bauxite refineries and alumina smelters. Aluminium production is the most carbon intensive industry in Australia and every state government has made secret electricity price deals with the big producers like Comalco in order to get these plants built in their state. Next we abolish the diesel fuel rebate for primary producers.
I saw a list of all these subsidies once, can't find it now, but over the years its grown pretty long.
I still think that a trading scheme is a better idea, it gives companies more time to adjust and provides more of an incentive to low carbon indutries rather than only focussing on disincentives to the "dirty" industries.
BTW, did you here the one about the scientist, the engineer and the economist who were marooned on a small desert island. They were living on coconuts and fish for months and were sick of it when a crate of baked beans washed up on the shore, but they didn't have a can opener. The 3 of them gathered around to ponder the problem. "Well" says the scientist, "How about we leave the cans in salt water until the chemical reaction of corrosion weakens the metal and we can open them"
"No" interjects the engineer "Lets get some driftwood and some of those rocks and make a lever and use solid engineering principles to open the cans"
"I've got a better idea" says the economist , "First of all, lets assume we have a can-opener"