Private jet carbon emissions by the wealthy: There's no flight shaming the rich

It was a sad week for aviation geeks as Boeing delivered its last 747 this week to cargo carrier Atlas after 52 years of service.

The "jumbo" was the first plane many Australians flew on overseas holidays, but it also brought hundreds of thousands of migrant families to this country. It was superseded by the A380 and other wide-bodied aircraft, but it still has a soft spot in the hearts of many travellers.

I've been thinking about big planes but also about small planes, too, thanks to Bill Gates, who flew to Australia late January, jetting about the country on one of his two Gulfstream 650ER private jets.

Since the pandemic, the use of private jets has soared. Because of the unreliability of commercial flights and the cost of first class, many businesses and well-to-do people opt for the flexibility and convenience of chartered flights, disregarding the fact that private jets, because they carry so few people, are estimated to be five to 14 times more polluting than commercial planes per passenger and 50 times more polluting than high-speed trains.

And then there are the very rich, in a category all by themselves - the "ultra high-net worths" as they are called. For this fraction of the one per cent a private jet is little more than an airborne limo, not only scooting across oceans but dashing a few dozen kilometres to visit the hairdresser.

Gates' private plane may have gone unremarked on if not for the fact that he was in Australia to talk about climate change and promote his sustainable technology businesses. His message was negative - there is "no chance," he said, that the world will keep global warming below 1.5 degrees of heating, which is the ambition of the Paris accord, and it's also unlikely it will be kept below 2.0, which climate scientists say would be catastrophic.

What outraged many was Gates' blithe assessment of the inevitable catastrophe, which climate scientists dispute, while jetting around the world promoting his sustainable and innovative technology business, burning 1800 litres of jet fuel per hour.

Those who fly in private jets argue that the small planes only produce about 4 per cent of all aircraft emissions, so it's a drop in the sky. But look at it another way - private jets emit more than 33 million tonnes of greenhouse gases annually, apparently more than the whole country of Denmark emits in a year.

The world's 500 richest people collectively saw their wealth increase by more than $800 billion at the height of the pandemic, and it's increasing exponentially, so there's every reason to believe the skies will become even more crowded with private jets in future. It's predicted that in the next decade 8500 new business jets will be delivered, 15 per cent above the forecast made a year ago.