Australia is setting itself against the US and will become a drag on global climate change efforts with the repeal of the carbon tax, prominent economist Ross Garnaut says.

The former government adviser says China, Europe and the US are gearing up for another big effort to address climate change and by scrapping its detailed and sophisticated carbon laws, Australia is going against this.

Bushfire seasons are predicted to worsen with climate change. Credit:Wolter Peeters

"With our existing policies, we're not ahead of any game yet but we're part of the game. We will be doing our fair share," Professor Garnaut said on Wednesday.

"With the repeal of the carbon laws, and in the absence of anything in their place, then we won't be doing our fair share.