Several weeks ago, Malcolm Turnbull accused the ALP of being fanatical about climate change. Now the head of the Business Council of Australia, Michael Chaney, has suggested that the ALP’s target of reducing greenhouse emissions by 60 per cent on 2000 levels by 2050 was “plucked out of the air” without the necessary research.
Is it true? Has the ALP gone feral in its hunt for green votes? To judge, it is necessary to go through the basics of climate policy.
Australia is a party to the United Nations Framework Convention on Climate Change, which aims to stabilise the atmospheric concentration of greenhouse gases at a level that would prevent “dangerous anthropogenic interference with the climate system”.
There is growing scientific consensus that in order to avoid dangerous climate change, policy-makers should do everything possible to ensure global average surface temperatures do not increase by more than 3C on pre-industrial levels (roughly 2.5C on 1990 levels). Beyond this point, the human and environmental costs could be very high and there is a risk of run-away climate change.
To limit temperature increases to 3C on pre-industrial levels, the evidence suggests the atmospheric concentration of greenhouse gases must be kept to between 450 and 550 parts per million (ppm) of carbon dioxide equivalent (CO2-e).
At 550 ppm CO2-e, there is still a significant risk average temperature increases could exceed 3C. There are also likely to be significant costs, including sea-level increases of several metres.
Given these factors, and the irreversibility of climate change (at least on a human timescale), a lower stabilisation target of between 450 and 500 ppm CO2-e would seem prudent. However, the chances of limiting the concentration of greenhouse gases to the lower bounds of this range are rapidly diminishing.
At present, the concentration is around 430 ppm CO2-e and is rising steadily each year. Confining the increase to 450 ppm CO2-e would require a Herculean effort. After all, there are still members of the federal government and business leaders who don’t believe climate change is happening.
In addition, stabilising the concentration of greenhouse gases in the atmosphere ultimately requires emissions to be equalised with the natural rate of absorption. Global emissions are currently approximately 45 billion tonnes of CO2-e per year, while the rate of natural absorption is only five billion tonnes.
If a 450 ppm CO2-e target was adopted, it would require a dramatic drop in emissions over a short timeframe. Hence, for political reasons, people are now suggesting a 550 ppm CO2-e target is more feasible, even though it entails greater risks.
There are different pathways that could be adopted to stabilise the atmospheric concentration of greenhouse gases at 550 ppm CO2-e. However, the science suggests that to achieve this target, global emissions must be cut by at least 25 per cent between 2005 and 2050, or from around 45 to 34 billion tonnes of CO2-e.
Policy-makers, and a growing band of entrepreneurs, are beginning to realise that the legal right to emit greenhouse gases will soon become a valuable commodity. Given this, there is likely to be a strong push to distribute these rights between countries on a per capita basis - an equal amount for each person.
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