''I am not out to scare the pants off anybody here, and I don't want to insult your intelligence with suggestions that climate change is a load of crap,'' he told the National Press Club this month. ''But if policymakers accept the science and its implications, you would expect them to follow through.'' The science says any increase in global average temperatures of more than 2 degrees compared with pre-industrial levels is ''getting into the dangerous category''. We are already halfway there, and there's only a limited amount of carbon and equivalent gasses we can release before we get there - our so-called ''carbon budget''. We are using it up at too fast a rate to hold the increase to 2 degrees. All is not lost if we pull back. The sooner we pull back gently, the less sharply we will have to pull back later. That was the message in the Climate Change Authority's report on targets released on March 5. Its finding was that Australia should lift its target for cutting emissions from 5 per cent below 2000 levels by 2020 to 19 per cent. Making that steeper cut now will avoid a much steeper cut later. Much of what the report suggests is easy. Adopting tougher motor vehicle emissions standards of the kind already in place elsewhere would cut running costs as well as emissions. And soon there will no longer be a local vehicle-building industry to object.

Another suggestion is to simply buy extra emissions reductions from other countries. They are going cheaply at the moment, and 2020 is looming too soon to bring about all the cuts in Australia. The globe doesn't mind where they take place. So far, the Coalition has been unaccountably hostile to the idea, presenting the purchase of cuts from overseas as a sort of moral failing. But we trade with other nations all the time and, for the moment, it's the only way to do what's needed. But it was the reactions to his report that shocked Fraser. He wasn't surprised by those of business - except by their scale and brazenness - but he was surprised by those of the government. ''It is the government's job to protect community interests,'' he says. ''Every politician pledges to do just that in the lead-up to every election campaign that I have heard.'' Instead, the government plans to abolish the Climate Change Authority. While not disputing the science, it shows no interest in lifting Australia's emissions reduction target. It wants to remove the carbon tax and is prepared to underfund the Emissions Reduction Fund that will replace it. It wants to axe the Clean Energy Finance Corporation and wind back the renewable energy target. If it believes the science - and it says it does - its thinking is unaccountably short term, unless you consider the three-yearly electoral cycle.

If an entire nation was sleepwalking towards catastrophe, it would be politically risky to wake it up. Could an entire nation - perhaps the entire globe - sleepwalk towards catastrophe? Al Bartlett thought so. He was professor emeritus in nuclear physics at the University of Colorado Boulder. Before he died last year, he spoke to the BBC's More or Less radio program, which deals with statistics, as did the interview. Bartlett was an expert on what happens when constant growth comes up against a hard limit. A YouTube video of one of his lectures is titled ''The Most Important Video You'll Ever See''. ''Steady growth means doubling over a certain period of time,'' he told More or Less. ''Suppose you have bacteria that double in number every minute. Now suppose you put one of these bacteria in an empty bottle at 11am and then observed that the bottle was full at midday. ''At what time was the bottle half full?''

The surprising answer is 11.59am - just one minute before midday because the bacteria are doubling every minute. ''Now, if you were an average bacterium in the bottle, at what time would you first realise you were running out of space?'' he asked. The answer might not even be one minute before it was too late. ''After all, at one minute before 12, the bottle was half full; at two minutes before 12, it was only a quarter full; and at five minutes before, it was only 3 per cent full, with 97 per cent of open space just yearning for development. ''At five minutes before 12, how many of you would realise there was a problem?'' How many of us would realise we were sleepwalking towards catastrophe?

Peter Martin is economics editor of The Age. Twitter: @1petermartin