While I was on holiday, I noticed a tweet that left me in no doubt about the subject of my first column back. It said: I genuinely think the next generation will not forgive us for what we have done to them and the world they will have to live in.

I, too, fear they wont. I dont know whether our political leaders ever think such thoughts, but it fills me with dread. Maybe the pollies think what I reluctantly think: With any luck, Ill be dead before the next generation realises the full extent of the hell our selfish short-sightedness has left them in.

But the climate seems to be deteriorating so rapidly Im not sure Ill get off that easily. I love my five grandkids, but Im not looking forward to the day theyre old enough to quiz me on what I did in the war. What was I saying and doing while our leaders were going for decades kicking the problem down the road as the easiest way to get re-elected?

Well, I was very busy writing about the shocking cost of living oh, and rising interest rates. Really? Is that the best excuse you can offer, Grandad?

We elected a bloke called Albo who promised to try a lot harder than his predecessors to reduce our emissions of greenhouse gases. He said hed cut them by 43 per cent by 2030. He was quick to put that target into law, and his people worked through the Christmas holidays to outline the safeguard mechanism hed use as his main measure to achieve the reduction.

While the rest of us were at the beach, Climate Change Minister Chris Bowen announced a few weeks ago that Australias 215 biggest industrial polluters running coal mines, gas plants, smelters and steelworks will have their emissions capped, with the caps lowered progressively by 30 per cent come 2030.

Businesses whose emissions exceed their cap will face heavy fines. To the extent they cant use cleaner production processes to reduce their emissions, theyll be allowed to buy carbon credits from other heavy polluters whove been able to reduce their emissions by more than required, or from farmers whove planted more trees.

Trouble is, it wasnt long before the experts started pointing to all the holes in the scheme. For a start, the combined emissions of these biggest polluters account for only 28 per cent of Australias total emissions.

For another thing, the notion that, as well as reducing the carbon were adding to the atmosphere, we should find ways to remove some of the carbon thats already there is a good one in principle, but riddled with practical problems. Whereas the carbon we emit may stay in the atmosphere for 100 years or more, the carbon sequestered by a new tree will start returning to the atmosphere as soon as it dies or is cut down. Its hard to measure the amount of carbon that tree-growing and other agricultural activities remove, which makes such schemes particularly easy to rort.

In his recent report into expert criticism of our carbon credit scheme, Professor Ian Chubb sat on the fence. While judging the scheme to be well designed, he identified various dubious practices that should be outlawed. And he stressed that big polluters must not rely on buying carbon credits to the extent that theyre able to avoid reducing their emissions in absolute terms.

A further weakness in the governments scheme comes from its refusal to prohibit any new coal mines and gas plants, despite the International Energy Agency and other international agencies saying the world wont have any chance of avoiding dangerous climate change if its relying on new gas or coal projects.

So, the scheme involves leaning on our existing 215 biggest polluters to reduce their emissions by 30 per cent, while allowing a bunch of new big emitters to set up, provided they then start cutting those emissions back.

Really? This is how were going to cut our total emissions by 2030? Seriously?

Last year a reader rebuked me for failing to make it clear that nothing Australia does to reduce its own emissions can, by itself, have any effect on our climate. Why not? Because climate is global, and were not big enough to have a significant effect on total world emissions.

The best we can do is set a good example, then pressure the bigger boys to do likewise. So far, weve been setting them a bad example.

Its the global scale of the problem that makes our efforts actually to increase our exports of coal and gas so irresponsible and, to our offspring, unforgivable. Were the worlds third-largest exporter of fossil fuels, after Saudi Arabia and Russia.

Australias emissions within our borders are dwarfed by the emissions from the coal and gas we export. But never mind about that. Lets just extract a few more shekels before the balloon goes up.