AAP: Australia should try to cut greenhouse gas emissions by 10 per cent by 2020, top climate adviser Ross Garnaut says, with immigration ruling out any greater reduction. In a major report released on Friday, Professor Garnaut says Australia is a special case and its emissions should be reduced by less than any other developed country. Australia’s high level of immigration, he says, meant it cannot realistically cut emissions as much as other wealthy nations. Prof Garnaut …