When a highly reputable international science journal publishes a claim that the Australian public is paying huge sums for carbon capture that isn’t happening, the government has a choice: it can address the issue head-on, or double down.
With potentially billions of dollars of public money and a big chunk of Australia’s emissions reduction target hanging on the viability of human-induced tree regeneration, or HIR, the government has chosen to double down.
Andrew Macintosh, an ANU law professor with specialist inside knowledge of the nation’s Emissions Reduction Fund, known also as the Australian Carbon Credit Unit (ACCU) scheme, is lead author of a peer-reviewed paper published last week by the London-based science journal Nature.
Macintosh resigned in 2020 after four years chairing the former government’s Emissions Reduction Assurance Committee. He has since become a leading critic of misuse by successive governments of tree carbon offsets to support ambitious carbon emission reduction targets.
In their Nature paper last week, Macintosh and 10 other specialists in ecology, tree biology and carbon accounting described what appear to be fatal flaws in administration of the “Safeguard Mechanism”, by which big fossil fuel polluters can pay for ACCU accreditation to offset their carbon emissions.
Offsetting by means of tree-planting – the vast bulk of ACCU accreditation projects – is supposed to deliver real, additional and permanent abatement. The main regenerative trigger for projects Macintosh’s team investigated was supposed to be ending grazing by farm animals on low-rainfall lands.
The team found that the very limited amount of regeneration that had occurred over four years in 182 tree regeneration projects in inland Queensland, NSW and Western Australia, compared with adjacent areas, delivered an average increase of just 0.8 per cent, almost all of that a result of identifiable rain events.
Macintosh launched a public broadside at Australian carbon offsetting in March 2022, sensationally declaring the market “a rort”. He claimed that graziers had been paid millions of dollars “to not chop down forests that were never going to be chopped down, to grow forests that are already there [and] to grow forests in places that will never sustain permanent forests”.
Confronting evidence that carbon farming under previous governments was so suspect that it should be excluded from our national carbon accounts, the incoming Albanese government was in something of a pickle. Its prized target of 43 per cent emissions reduction by 2030 looked very vulnerable indeed.
In 2022 new climate change minister Chris Bowen named former chief scientist Ian Chubb to investigate the ACCU scheme, including Macintosh’s allegations. Drawing on a 2021 study commissioned by the Emissions Reduction Assurance Committee – the same body Macintosh had left in 2020 – Chubb concluded that the scheme was basically sound and critics were letting the perfect become the enemy of the good.
The debate picked up. In March last year a team of ANU legal and scientific specialists, including Macintosh, responded that Chubb had ignored the clear failings of the 2021 study, misrepresented a critical report by the Australian Academy of Science and skated over awkward questions about the HIR projects.
Coinciding with this month’s publication of the critical Nature paper, the Clean Energy Regulator, which manages the ACCU scheme, publicly declared faith in the HIR method and the integrity of the scheme’s carbon credits.
The CER declared its scheme to be robust, with “a high degree of integrity” and “a raft of compliance tools at its disposal”, adding that ACCUs were underpinned by “rigorous assessment processes” and “a comprehensive set of audit requirements.”
On ABC breakfast radio Chris Bowen added to the pile-on. He referred to a 2023 study by an ANU forest scientist, Cris Brack, as evidence that the HIR projects were delivering regeneration “and proponents are implementing the project activities”.
Bristling at a suggestion that Macintosh’s claims called for a “rethink” of the scheme, the minister said: “Professor Chubb and Associate Professor Brack are the people who have been commissioned, and there is a different result from their work.” In other words, the fact of their being commissioned should end the debate.
Macintosh is being represented as a man with a grudge against the system which he left in 2020. But he served and led that system for years, and the claims he makes are getting independent scientific support. Those simple facts alone should be enough to sound alarms.
Australia has always been a leading global advocate for carbon offsetting schemes and this large land-based scheme has been held up as an example for others. But its ultimate value is in its ability to draw down atmospheric carbon, and that will not be served by its keepers closing ranks and dodging uncomfortable questions.