Prime Minister Scott Morrison has long suggested Australia can do little to influence the Earth's changing climate because its emissions make up just 1.3 per cent of the world total.

The imputation, by extension, is we're too small to make a difference.

Such arguments have been made possible — in part — thanks to the international carbon accounting methodology most commonly used to apportion greenhouse gas emissions to individual countries.

Sometimes referred to as territorial-based carbon accounting, this system attributes emissions only to activity that takes place within a country's borders; for example, through the combustion of coal for power generation.

This means that emissions are not always fully linked to economic activity or, for that matter, to the country where manufactured products are ultimately consumed.

For example, a country might manufacture a car made of steel produced by using imported coking coal, and power derived from imported thermal coal. That car may then be sold back to the exporter of the coal.

Under international carbon accounting rules the emissions released to make the car are attributed to the country where it was manufactured.

What proportion of world emissions does Australia make up when fossil fuel exports are taken into account? ( Supplied )

By extension, the emissions embedded in Australia's vast exports of coal and LNG are not counted in Australia's domestic total under the territorial-based carbon accounting rules.

There is, however, a growing recognition — including from some fossil fuel exporters — that emissions should also be tallied according to a company or country's economic activity.

That includes accounting for the emissions embedded in fossil fuel exports.

For companies, this exercise is sometimes referred to as scope 3 analysis.

So when Mr Morrison says Australia is responsible for just 1.3 per cent of the global total, there is a counter argument that is gaining traction: once exports of fossil fuels are included, the total is much greater.

Tech entrepreneur and outspoken climate change commentator Mike Cannon-Brookes, for example, recently claimed in a tweet that Australia's share of the global emissions rises to more than 5 per cent once the emissions embedded in fossil fuel exports are included.

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RMIT ABC Fact Check put this claim to the test.

Australia's exports of coal and LNG have boomed in recent years.

According to figures from the Department of Industry, Innovation and Science, in 2016 (the latest year for which comparable global emissions data is available), Australia exported 391.2 million tonnes of coal, made up of 201.9 million tonnes of thermal coal (used mainly for power generation) and 189.2 million tonnes of metallurgical coal (used mainly for steel production).

That was more than double the 186.7 million tonnes exported in 2000.

Australia's exports of LNG have also boomed, increasing more than five-fold over the past decade.

In 2016, Australia exported 45.0 million tonnes of LNG. The latest figure is now much higher, around 75 million tonnes over the year to June 2019.

By our estimate, in 2016 Australia's fossil fuel exports (including coal, LNG, crude oil and liquefied petroleum gas) contained approximately 1,160 million tonnes of greenhouse gas emissions. This was more than double Australia's domestic emissions of 552 million tonnes.

Add the two together and it turns out Australia's emissions made up about 3.6 per cent of the global total.

If you restrict the calculation to the combustion of fossil fuels only, as is common with this type of analysis (leaving out sectors such as agriculture and land-use from the domestic and global totals), Australia's share of global emissions rises to about 4.8 per cent.

But the equation should not be this simple — at least not in Fact Check's view.

If Australia is to be held accountable for its fossil fuel exports, its fossil fuel imports should likewise not be counted in its domestic total.

For consistency, that responsibility should be attributed to the country selling the product.

Put another way, if Australia's "exported" fossil fuel emissions are to be measured against a global total, "imported" emissions should also be taken into account so as to avoid double counting.

Remove imported fossil fuel emissions from the equation and Australia's share of world emissions from fossil fuel combustion falls from around 4.8 per cent to about 4.4 per cent. And its share of total global emissions falls from 3.6 per cent to 3.3 per cent.

This is somewhat less than the figure claimed by Mr Cannon-Brookes. For this reason, Fact Check concluded Mr Cannon-Brookes overstated the extent to which Australia's domestic emissions, together with its exported emissions, contributed to the global total.

A different question is whether a resource-rich country such as Australia should be accountable for emissions embedded in exports, and whether emissions should be attributed to the seller or user of fossil fuels.

And whether there is a moral argument that they should.

Even if you don't accept that notion, such a stocktake is still useful — not least because it highlights the level of risk faced by a big resource exporter like Australia, should the world intensify its action to curb emissions.