Ancient Indigenous Australian bush-burning could be used around the world to radically cut greenhouse gas emissions, according to United Nations research, which also challenges Prime Minister Tony Abbott's refusal to embrace the purchase of international carbon credits.
Mr Abbott has previously said buying overseas offsets sends money "offshore into dodgy carbon farms in Equatorial Guinea and Kazakhstan". The government this month delayed considering the measure until 2017 or later, saying it would rather make cuts domestically.
This is despite doubts over whether the government's Direct Action plan will be enough to meet Australia's global climate commitments, and calls from business and green groups that say international credits offer a cheaper way to cut emissions.
The preliminary findings of a $3 million United Nations University research project, largely funded by the federal government, said controlled wildfire methods historically used by Indigenous Australians, and robust methods to measure their benefit, could be used by nations around the world, cutting global emissions from wildfires by as much as a half.
Australian companies could then buy credits from overseas projects, knowing the emissions cuts were genuine and their methods credible.
Indigenous people have historically managed the savannah regions of tropical northern Australia through low-intensity "patchwork burning" early in the dry season, which can help prevent uncontrolled fires later in the season, and so cut emissions.
Wildfires are a significant source of greenhouse gas and their prevalence is expected to increase because of climate change. Each year wildfires burn up to 4.5 million square kilometres globally – an area more than half the size of Australia.
There are 34 savannah-burning projects generating carbon credits under the Carbon Farming Initiative in Australia, according to the study by the United Nations University think tank.
They use "ground-breaking" methods to measure emission reductions, including NASA satellite monitoring to measure cuts and verify carbon credits.
The two-year study assessed the feasibility of transferring the methods to nations in Asia, Latin America and Africa.
Preliminary findings were presented to the government as part of submissions to its post-2020 emissions cuts.
It showed more than 20 nations had shown interest in the technology, including Brazil, Mexico, Indonesia, Papua New Guinea, South Africa, Zimbabwe, Peru and Cambodia.
However, global awareness of the potential was not high and a "globally significant opportunity for emissions reduction is not being properly exploited", the research found.
It said the savannah-burning method, if exported, would be a credible international carbon credit that met Australian standards and avoided the pitfalls of other types of offsets
It said European colonisation around the world had suppressed indigenous fire management activities, and programs to reintroduce them had not used methods to quantify emission cuts.
A spokesman for Environment Minister Greg Hunt said the research was not primarily about "international units" and the government's Emissions Reduction Fund focused on reducing emissions in Australia.
If other countries now adopt the methods, it showed how the ERF "can support pioneering work in Australia which can then be adopted by other countries to reduce global emissions", he said.
