You didn't answer the direct question. Nothing can be done (by Oz) that would make the slightest difference to the world's CO2 levels. Answers like "I believe" etc. are not really answers at all. It is like the typical politician's evasive answer "That's not the question - the real question is -etc." and then go on to ask something totally unrelated.
It is not "rocket science" (as they say) - there is nothing Oz could do (even disappear from the face of the Earth) that would make the slightest difference.
But action could be taken that would help if GW/CC is actually happening and could be of benefit to Oz even if it is not happening. (Like Snowy 2.0 - a bit pointless, but it would do no harm and would keep a lot of people in employment).
I thought I did answer the question (see quote below).
"OZ" is responsible for >1% of world carbon emissions, so I guess internally we could only reduce world emissions by 1% - most people would say that is more than "the slightest difference". Regardless, I want to vomit every time I hear this argument. Its like saying "why should I vote", "why should I pay tax", "why should I donate" or "why should Henri stop flying?" - none of these will make "the slightest difference" in the grand scheme of things.
There is also a lot of action that could be taken that would make a much bigger difference with zero economic pain - did you read the Forbes article? The risk associated with building a new coal fired power station in Australia is high - no Australian company is prepared to take that risk. It seems certain that coal (and nuclear) will become far more expensive than renewables within the lifespan of a new power station.
Schemes like Snowy 2.0 and a second Basslink will add reliability to a growing renewable energy generation network but more important is the need for small scale energy storage - probably hydro - distributed across the country. This combination will become the new "baseload".
Years ago, I did a thumbnail calculation of the expected rise in atmospheric CO2 from human CO2 emissions and posted the result here. Probably in the "Global Warming' thread. Turns out if humans stopped burning fossil fuel, atmospheric CO2 would stop rising. (That means no I don't)
Edited by gruntguru, 19 March 2019 - 22:57.