OPINION: In December 2015 the world's attention will be focused on reaching agreement to cut greenhouse gas emissions as part of the Paris climate negotiations.

As Australia is already one of the highest per capita emitters in the world, cutting our emissions will be tough. But the problem for Australia is even bigger than being a major emitter. We are also one of the biggest exporters of fossil fuels. Our gas and coal exports generate many more emissions than we consume, while the proposed Queensland mega coal mines will add even more.

Why should this matter for our "emissions budget", as it is often called? Forget about emissions for a moment and think of it this way.

Suppose that a country produced and exported large amounts of tobacco to a developing country that did not have health warnings for smoking. Given what we know about the links between smoking and death and disease, the exporting country is plausibly implicated in the harm caused and is morally responsible for at least some of that harm.

Another example is uranium exports. Setting aside general objections to uranium exports, there are good reasons why many countries place restrictions on the destinations of their product. The risks of weapons proliferation, accidents at reactors, storage issues and so on are just too great with some countries to countenance an export program. If one country knowingly exported uranium to another country where safety was lax, we could rightly accuse it of being irresponsible and having a share in the blame if an accident were to happen.

We could (and do) make similar analogies with the exports of other products, such as live animals or hazardous waste.

What all of the cases above have in common is that they cause harm in a morally significant and blameworthy way. Avoiding causing significant harm should provide a powerful and important constraint on our actions and/or make us liable for the consequences.

Now back to coal and gas. Fossil fuels are a commodity that we know cause harm when we export them for their standard uses. We know that gas or coal exported from Australia to China will generate greenhouse gases and the links between increasing greenhouse gas in the atmosphere and harms caused are strong.

Moreover, there is potential for this chain of events to harm the significant interests of people everywhere. These harms could include: increased vulnerability to disease, crop failure, water shortages and the impacts caused by severe weather events such as severe cyclones (sound familiar?).

The harm caused is like the harms caused by tobacco in morally relevant respects, in that exporting countries contribute to knowingly harming the significant interests of others in ways that could, in many cases, be avoided.

In wealthy countries such as Norway and Australia, the export of fossil fuels may be significant to the economy, but they are not the only means for those countries to maintain a high standard of living.

If it is the case that fossil fuels are exported in the knowledge that they cause significant harm to human interests and the practice could be avoided, then resource-exporting nations have a prima facie responsibility for the harms that they cause through their exports.

If this argument is correct, then it leaves Australia with a huge problem.

According to the World Bank, the per capita emissions of several OECD countries in 2011 was: Germany (8.9mts), USA (17mts), and UK (7.1mts). If we count exported emission in per capita terms, then Australia's emissions roughly triple from a starting point of close to 20mts, which is a massive increase. This would put Australians in gold medal territory for per capita emissions in the world.

Even if we recognise that importing countries bear 50 per cent of the responsibility, Australia still gets a huge increase in its carbon budget.

When looked at in this way, we have a clear moral requirement to take responsibility for our harmful exports. What does this mean in practice? As a minimum, we should stop causing these harms by winding down our investments in coal and gas. The rush to open new coal mines in particular is morally dubious.

It also puts extra pressure on us to reduce our domestic emissions profile by reducing our own dependence on coal for electricity. And finally, if we are responsible for climate harms we need to make recompense to those who have been harmed in other countries.

Some will object about the financial cost or the loss of jobs that this kind of argument entails. These are real issues. Yet fundamentally climate change matters for a moral reason - it is unjust because of its impacts on our wellbeing. And it is high time that we reinjected some of these moral concerns into our thinking about what we need to do.

Professor Jeremy Moss is an ARC Future Fellow and member of the Practical Justice initiative in UNSW's Faculty of Arts & Social Sciences (Climate/Justice Stream).

This opinion piece was first published on ABC's The Drum.