Christine Milne (Tasmania, Australian Greens) Share this | Hansard source

You can say it is rubbish, Senator McGauran, but that is the science. Thermal warming of the oceans is already occurring and, in addition to that, there is the acidification of the oceans—that is, the oceans are becoming more acidic as a result of the take-up of carbon dioxide—and that is weakening the coral reef systems and threatening the whole marine food chain. Creatures that require calcification of their shells cannot make their shells with the level of acid in the oceans, which means that the krill and the whole marine food chain are threatened. That is the reality.

At the CRC in Hobart, which is looking at this issue, it is said that 450 parts of atmospheric CO2 per million is the tipping point for ocean acidification at which those creatures are lost. I would not want to be taking a 50 per cent chance; I would want to be saying, ‘We need to actually increase the probability of our getting a safe climate.’ If we say that, we have to answer a more difficult question: how sure do we want to be that we do not cross the two-degree guardrail and how sure do we want to be that we can actually constrain warming to less than two degrees? I would say that the precautionary principle says that we want to be much more certain than we would be by only giving ourselves a 50 per cent chance.

Here we come to the issue of the carbon budgets. Professor Will Steffen said quite clearly in his presentation to the Multi-party Climate Committee, which is now readily available, that if global emissions peak in the year 2015—that is, five years from now—we can stick to a reasonable budget by reducing emissions by about 5.3 per cent every year for about 30 years. So if we started we could do it. But, if we postpone the peak beyond 2015 until, say, 2020, global emissions would have to fall by nine per cent a year for two decades, and just about everybody says that would be virtually impossible to achieve.

We are at a critical time for the future of the planet. This is not something we can come back and revisit in 2020. These are the years in which this generation will make the decisions that will determine what life will be like for every generation after us in terms of species extinction and marine food chain issues. There are no more critical questions to answer than: how high are you prepared to let the temperatures go? How much warming will we accept? What degree of probability do you want to achieve where we set out to achieve a safe climate? What is the carbon budget that does that and then, inside that carbon budget, how much is Australia’s fair share?

I will go to the actual carbon budget. Professor Steffen said to maintain a 75 per cent probability of staying within a two-degree temperature range, humanity can emit 1,000 gigatonnes of CO2 between 2000 and 2050. To stay at two degrees, 1,000 gigatonnes, 2000 to 2050 and, already in the nine years from 2000 to 2009, 305 gigatonnes were emitted—in other words, over 30 per cent of the budget between 2000 and 2050 has been emitted this decade. It simply cannot go on if we are to meet a carbon budget that can constrain global warming. So we have to not only decide the temperature target; we have to decide how we are going to achieve it.

If you recognise that a third of the budget has already gone that puts you in the frame of saying: ‘Developed countries, you are on notice. A five per cent reduction is laughable. It’s nowhere near in the ballpark.’ As for the coalitions suggesting its policies can achieve the kinds of reductions we are talking about here, it is errant nonsense, absolute nonsense. If you are going to get the kind of trajectory that has developed countries taking on their fair share, we have to know what the principles are that the Australian government is going to put forward.

We have said in public fora, ‘Australia will contribute its fair share.’ But what does that mean? What is our fair share? What are the principles that we are going to use to underpin that fair share? Ethical approaches to this in any kind of global discussion contain debates about: do we have an equal per capita allocation so every person on earth gets the same carbon budget? If we were to do that, rich nations like Australia would need to reduce our emissions to about four tonnes of CO2 per person by 2020. Now in Australia we are emitting 27 tonnes per capita. Currently, we are on 27 tonnes per capita. We would need to get that down to four tonnes per capita, if you used a baseline year and went on equitable access to the world’s carbon budget.

If you took into account our historical responsibility and the development rights of developing countries, that is the kind of notional view that you would come to. Instead of that we are seeing in the global negotiations a cost-equalisation approach where we are trying to divvy up the pie so that the economic cost borne by nations, particularly rich nations, is about the same. That is just not going to work, because some developed countries are going to say, ‘Hey, that’s not fair. We have been working to reduce our emissions to transform our economy for a very long time. We’ve made decisions to stabilise and reduce our population. You in Australia have done nothing for decades. You are deliberately increasing your population. You haven’t put into place those frameworks that you should have, so we are not going to accept that approach.’

The only way you can do this is to take an ethical approach which, either way you look at it, will see Australia being given a very small share of this global carbon budget that we have got left out to 2050. If you agree that a third of our budget to 2050 has already gone, it means the steepness of the reductions has to be very steep. That means deep reductions in Australia and a rapid transformation of the Australian economy. That is the debate we should be having in Australia today—not whether global warming is real, not whether it is human induced, but rather what degree of warming we are prepared to accept. What level of probability do we want that we will constrain global warming to far less than two degrees? In that context, what is the global budget and what is our fair share?

Before Minister Combet goes to Cancun next week, Australia needs to know: what are the principles that Australia is going to put forward? All I have seen is that we are there rent-seeking again, saying ‘We’ve got an increasing population.’ Yes, we have because we choose it. It is a policy decision to do that, and that is not something other countries are going to be sympathetic to, so we need an explanation from the government as to those principles.