Four Outback towns in Queensland experienced their hottest May night on record last Saturday. In one of them, Birdsville, the temperature didn't fall below 25.4 degrees: the May night-time average for the town is 12. The next day, 700 kilometres to the northwest and almost at the Northern Territory border, it reached 38 at Urandangi aerodrome, which is ridiculous.

It seems that gone are years with cooler May days and doona-nights heading into winter. Sundown here in the South East is already far too early – nearer 5 than 6 – but mozzies are still biting and there are too many sultry days. Hot and humid Noosa on Labor Day weekend felt more like Brissie in February.

While Urandangi sizzled on Sunday, in Canberra Malcolm Turnbull went to visit the Governor-General to request a double dissolution of Parliament. He had been threatening this for a while if the Senate didn't pass his bill to resurrect the Australian Building and Construction Commission. He had recalled Parliament to give them one last chance; but they refused to be bullied. I have yet to meet anyone who believes such a policy is necessary, or that it is an issue worthy of dissolving both houses and the considerable costs of a general election. The last double dissolution was in 1987.

My third federal election will take place on 2 July, when I will be in the UK. Between now and then will be eight long weeks of campaigning, for at least one whole day of which I will be at 35000 feet and blissfully oblivious of the policy ping-pong beneath.

The most important issue is without doubt how this nation will tackle climate change: how it will execute its international obligations to reduce global carbon emissions; how it will prevent further harm to the Great Barrier Reef caused by a warmer, more acidic ocean; how will it transition from fossil fuels to renewable energy; how will it scale back rampant consumerism into much more sustainable living.

'Jobs and growth' is not the most important issue, but it is already the most annoying slogan. In the Turnbull government's budget last week, Treasurer Scott Morrison declared that Australians know that their country's future depends on how 'we transition from the unprecedented mining investment boom to a stronger, more diverse new economy', but he didn't finish the sentence. '…A more diverse new economy based on renewable energy', is what he should have added.

Labor's climate action agenda, while more ambitious than that of the Coal-ition, falls far short of brave and bold. Brave and bold is what is required. So scared is Labor of suggesting anything that could be construed as a great big new sort of carbon tax, it has compromised (see here), instead of declaring that all remaining coal deposits must stay in the ground. Adani Mining should be shown the door. No more faffing; no more approval conditions tacked on. Adani, go home.

Labor's problem is Australians' cognitive dissonance: that is, they have inconsistent thoughts or beliefs, especially relating to behavioural decisions and attitude change. So, they might be aware that the koala is virtually extinct in South East Queensland, but they don't protest the relentless encroachment of development into koala habitat. They know there is more plastic in the ocean than fish, and that fish populations have collapsed, but it doesn't stop them going to buy kilos of barra to fling on the barbie next weekend, and it wouldn't even occur to them to ask their fishmonger if the prawns were sustainably caught. They want more jobs for Central Queenslanders, but the Galilee Basin coal mines will render the Reef beyond bleached, for sure, and ongoing drought will no longer support 29 million cows eating their way across a parched continent.

This problem isn't confined to Australians, of course. But it's particularly marked here because many people can't begin to imagine modifying their beachy keen lifestyle. Australians don't want to go it alone on the world stage, in case they lose out competitively, but in fact they should be a global leader. Blessed with more sunshine than practically anywhere else, they should set an example of what to do with it. Like slip slap slop, but orders of magnitude greater.

Sustainability is about more than recycling or taking your own shopping bags to the supermarket – although, dear gods, not enough people even do that. It's about owning fewer gadgets and repairing them rather than throwing them away; using water sparingly every day; eating less meat; reducing your power consumption; catching fewer planes; owning fewer cars; using public transport; owning fewer dogs; having fewer children; thinking beyond your own little bubble.

It reached 28 today in Brisbane, as predicted. The weather system that kept temperatures up in the far west over the weekend, and subsequently brought much needed rain in some places, rolled mistily over the city yesterday morning. There's still cloud lingering today, which has meant dramatic front lines and a beautiful sunset.

We're fortunate in this corner of the globe, but time and luck are running out. The necessary transition will be extremely challenging, and you need to think long and hard over the next couple of months about who will be best equipped to face the challenge. This time, you can't put it off until next time.