Climate Change Commission fell "well short" in carbon-cutting advice, lawyers argue
Due to a combination of maths errors, the Climate Change Commission failed to propose sufficiently ambitious carbon-cutting budgets, a group of climate-concerned lawyers argued in the High Court today. Last year, the independent commission proposed cuts to net emissions of 7 per cent by 2025, 20 per cent by 2030 and 35 per cent by 2035. The Government has indicated it will broadly follow this path. In its advice, the commission told the public this course will both lead the country towards net-zero by 2050 and contribute to global efforts to limit warming to 1.5 degrees Celsius. Lawyers for Climate Action told High Court justice Jillian Mallon that the commission used irrational maths to justify the latter. Using maths that accurately reflects what the atmosphere sees each year, New Zealand would have to make far deeper cuts to carbon dioxide to be compatible with 1.5C, the law group argued. READ MORE: * Why the Climate Change Commission is being taken to court * COP26: New Zealands new climate pledge is a step up, but not a fair share * Legal action against the Climate Change Commission: Necessary, influential and helpful The lawsuit also names Climate Change Minister James Shaw, who receives the commissions advice, sets budgets and helps determine the countrys carbon-cutting pledge (the Nationally Determined Contribution or NDC) under the Paris Agreement. On behalf of the law group, Jenny Cooper QC noted the Paris Agreement asks the world to limit warming to well below 2C and pursue efforts to achieve 1.5C. But the Zero Carbon Act only names 1.5C. The law requires the commission to suggest carbon budgets to bring emissions down to net zero by 2050 and to contribute to global efforts to limit warming to 1.5C. To determine if the commissions advice aligned with 1.5C, the agency turned correctly, Cooper said to a special report produced in 2018 by the expert climate science body, the Intergovernmental Panel on Climate Change (IPCC). This report concluded that, compared to 2010 levels, carbon dioxide emissions needed to fall by between 40 and 58 per cent to give the world a decent shot at 1.5C. There were different goals for other greenhouse gases: including the reduction in agricultural methane of between 24 and 47 per cent by 2050 which was echoed in the Zero Carbon Act. In its final advice, the commission compared gross carbon dioxide emissions which excludes whats absorbed by forests in 2010 to net emissions (which includes the carbon sequestered by trees). By this standard, carbon dioxide emissions would fall 55 per cent. After summarising the history of climate science, international accords and national legislation, Cooper argued that net 2030 emissions must be compared to 2010 net emissions. Climate scientists and economists Piers Forster, Stephen Gale, Joeri Rogelj, Ralph Sims, William Taylor and Donald Wuebbles provided written evidence that the IPCC report uses net-net comparisons, and that the commission made a maths error to contrast gross with net emissions to assess compatibility. Forster and Rogelj were both authors for the IPCCs special report on 1.5C. Cooper said decisions to compare gross historical emissions to net emissions dated back to the Kyoto Protocol, which required developed nations to cap their greenhouse gas outputs. Back then, it was argued that countries such as New Zealand with lots of forests already sucking up carbon could have a harder time. So it was agreed that 1990 would act as a clean slate: as long as old forests are left alone, only the carbon sequestration of new forests would be counted. In that way, New Zealands greenhouse goals could focus on net emissions, and be compared against its gross emissions in 1990. In its statement of defence, the commission said the gross-net approach was used because New Zealands forests have been a net sink of emissions. Both of these approaches are consistent with the international target-accounting guidance and appropriate to the circumstances they are being applied to. But Wuebbles, an atmospheric scientist at the University of Illinois, disagreed. Past agreements, such as the Kyoto Protocol, were based on what could be accomplished, not on the best science. I consider that the commissions approach of looking at the past is not the proper way to move forward on climate action. Kyoto Protocol maths has two categories: gross emissions (this includes all fossil fuel emissions and refrigerant gases) and another known as land use, land use change and forestry (LULUCF). Under this system, permanently chopping down a forest would fall into the second category. However, Forster wrote the IPCC system instead uses emissions sources (such as fossil fuels) and sinks (such as forestry and carbon capture). In contrast, deforestation would fall into the former category. Under Kyoto, LULUCF can either be an overall source of carbon, or a sink. Under the IPCC system, the second category is, by definition, the latter. In addition, by using 2010 gross emissions, the commission would set a new clean slate, at a higher baseline. Gross emissions increased between 1990 and 2010 . Rather than targeting sources of gross emissions, the country planted large amounts of exotic pine to meet its Kyoto Protocol obligations from 1993 to 2001, and then stopped. These forests sucked up carbon as they grew, but are coming up for harvest, a point when the carbon stored within them is added back into the atmosphere, under international carbon accounting rules. Net greenhouse emissions rose from 1990, then dipped from 2006 to 2010. Net emissions are on the rise again, expected to peak around 2026. These circumstances make the IPCCs choice of 2010 as a baseline particularly inconvenient for New Zealand. The law group is asking Justice Mallon to declare that the commission acted unlawfully by using gross-net comparisons. The error undermines both the three carbon budgets out to 2035 and the advice to the Climate Change Minister on the carbon-cutting pledge required under the Paris Agreement, the group argues. James Every-Palmer QC also appeared on behalf of Lawyers for Climate Action, making a detailed case against the commissions maths. He argued that once the commission had worked out the emissions reductions required to be compatible with 1.5C, using the correct maths, then aspects of fairness could be applied. This assessment could balance out calls for New Zealand to do more than average, particularly as a developed nation, against arguments to do less: to protect the economic interests of young people and Maori, for example. Every-Palmer said if the country chose to do less than its fair share, that should be clear. We cant say were doing the same mahi as everyone else. In a response to the claims, counsel representing Minister Shaw provided a calculation using a net-net comparison and a different accounting method following the preferences of Lawyers for Climate Action. The calculation concludes the NDC will reduce emissions 35 per cent. But it uses 2005 (not 2010) as a baseline. The NDC includes both emissions reductions that will occur within New Zealand (under the three carbon budgets) and action that will be purchased from other countries. Scanning the commissions 418-page final advice, Cooper noted a lack of emphasis on meeting 1.5C. The document indicates the 2050 targets (such as net-zero carbon) is the commissions most relevant concern. The trajectory of those cuts which Lawyers for Climate Action argue is critical against the IPCC roadmap is described as an additional consideration. Cooper challenged the commissions conclusion that the IPCC report doesnt set out prescriptive pathways for individual nations. Lawyers for Climate Action say the carbon budgets fall well short of the action required to avoid catastrophic climate change. The group want the commission and Government to significantly boost climate ambition, taking enough action within New Zealand over the next eight years to align with the 1.5C temperature goal. This would require extremely large cuts to carbon dioxide emissions produced by the transport, industrial and power generation sectors. Cooper said this would significantly impact the way people worked and lived. No ones under any illusion that this is an easy thing to do. Lawyers for Climate Action will continue to argue their case Tuesday. Counsel representing the minister and the commission are expected to defend these claims from Wednesday, and the hearing is likely to last until Friday. The hearing coincided with the release of an IPCC report, which will update the world about the effects that catastrophic warming will have on the planet and the ability of the society to adapt.