On 30 November representatives of the world's nations will gather in Paris to work towards a Universal Climate Agreement to keep global warming below 2 degrees Celsius.
This will be the 21st conference of the parties to the United Nations Framework Convention on Climate Change. The task before them is formidable.
Different nations vary greatly in how much greenhouse gas they currently emit annually. China is now at the top of the list with about 23 per cent of the global total followed by the USA with about 16 per cent. Australia contributes 1.3 per cent. However, these figures are misleading and unfair.
Environmental justice will be part of the discussion in Paris, and increasingly in future conferences. The principle of justice on which the United Nations itself is founded says that each person is of equal value no matter which nation, ethnic group, religion or gender they belong to.
It is a melancholy truth that poverty is what keeps global greenhouse gas emissions from rising much faster than they are at present.
For instance, according to the World Bank, each Australian contributes about 16 tonnes of carbon dioxide per year, while each Bangladeshi contributes a little more than one third of a tonne. Other calculations put the Australian per capita figure at 26 tonnes annually.
Greenhouse gas emissions are waste products of households and industry. If we think of the Earth's atmosphere as a global garbage tip of limited size for these waste products, the figures above mean that each Australian is using 48 times more of that tip than each Bangladeshi.
Yet if we remember that Bangladesh, a low lying country on the Ganges delta, is at great risk of sea level rise and extreme weather events, it is obvious that Bangladeshis are going to suffer more than perhaps anywhere else from the climate change they did not cause.
This is not a matter for individual blame or praise. But the principle of justice, which most Australians would support, requires that from now on greenhouse emissions per person should converge over time towards a global average.
The task of doing that cannot be left to individuals acting voluntarily, any more than payment of taxes can be voluntary. If taxes were voluntary there would be little cash available for national governments to provide for the common good of all citizens. Similarly national governments must be mostly responsible for the achievement of global environmental justice through taxation and regulation.
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