[Greg McDonald]

From NEWS.COM.AU:

Passengers on all international flights should pay a compulsory greenhouse levy, an Australian academic says.

Andrew Macintosh, associate director of the Australian National University's Centre for Climate Law and Policy, recommends a $20 levy on passengers flying Sydney to London but lower levies on flights from developing countries.

Mr Macintosh has released an ANU study he co-authored which warns greenhouse gas emissions from international flights will more than double by 2025 as more people fly.

Global efforts to tackle soaring aviation emissions were not working, partly because of legal problems, and voluntary greenhouse levies were ad hoc, he said.

"Having a single mandatory scheme would be far better for the industry and the environment," said Mr Macintosh, who was formerly active with the left-leaning think tank the Australia Institute.

"An emission charge could be imposed at a low level of between $5 and $15 per tonne of CO2 on all developed country flights."

Passengers on flights from developing countries could pay a lower amount.

Money raised from the levies could be used to reduce emissions from deforestation, Mr Macintosh said.

Emissions from international flights will increase by between 111 and 144 per cent by 2025, more than previously thought, the study finds.

Economic growth and broader airline coverage will see emissions triple by 2050.

"While aviation is not currently one of the main drivers of global warming, the growth trajectory of the industry suggests it could become a significant factor over the coming decades," the report said.

The aviation industry has resisted calls for mandatory measures to address emissions, pointing to energy-efficient technological changes as the solution.

But such changes would not go far enough to contain aviation emissions, the report concluded.