Climate-concerned lawyers failed to convince a judge that the Climate Change Commission’s carbon-cutting maths was wrong.
High Court justice Jillian Mallon dismissed all the grounds of review argued by Lawyers for Climate Action. She found the commission correctly interpreted the law and had the power to make the choices it did – even if these were controversial.
But she agreed that the commission’s “presentation of its analysis had the potential to mislead” when discussing whether its advice aligned with efforts to limit warming to 1.5C.
It’s been a long wait for the High Court ruling, which came more than eight months after the judicial review hearing finished. Since the hearing, the Government has used the commission’s advice to write its emissions-cutting plan.
Climate Change Minister James Shaw said the undecided case influenced his decision not to ask Cabinet for a tougher carbon-cutting goal to take to the recent COP27 climate summit.
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In late February and early March, lawyers debated whether the Zero Carbon Act had been followed correctly by the influential commission.
The law, passed in 2019, governs how the country will transition to a net-zero economy. Lawmakers said the carbon-cutting path should “contribute[e] to the global effort under the Paris Agreement to limit the global average temperature increase to 1.5C above pre-industrial levels”.
Above 1.5C, the health, economic and environmental effects of climate change will be supercharged – and the world is currently 1.1 to 1.2C warmer than the pre-fossil-fuel era.
The commission’s advise matters, because the Government uses it to set climate targets (essentially budgets for how much greenhouse gas can be emitted) and policies.
Shaw also asked the commission if the 2030 climate goal – New Zealand’s Nationally Determined Contribution or NDC – at the time was consistent with global efforts to limit warming to 1.5C.
At the same time, it said its emissions budgets – which would only go part of the way to meeting the NDC – were compatible with “contributing to the global effort to limit warming to 1.5C.”
And others thought the commission’s proposed budgets and NDC advice did not cut carbon emissions quickly enough.
Extreme weather brings rougher growing conditions, which can cause food shortages and price rises.
The lawyers’ group hoped to send the commission back to the drawing board and require the Government to tighten its budgets, strengthen its NDC and update its plan with more ambitious emissions-cutting policies – or admit it wasn’t taking sufficient steps to align with 1.5C.
In court, the lawyers pointed to a special report by climate expert body the Intergovernmental Panel on Climate Change (IPCC). The body found that, for a decent shot at 1.5C, the world must reduce its output of carbon dioxide by between 40 and 58 percent by the end of the decade, using 2010 as a baseline.
The commission’s conclusions on the NDC and domestic emissions budgets relied on a controversial comparison: contrasting 2010 gross emissions (which does not include the carbon absorbed by forests) against 2030 net emissions (which does count trees).
Seven experts, including two who worked on the IPCC’s 1.5C report, criticized this comparison in written testimony to the court.
Based on a gross-gross comparison, carbon emissions in 2030 on the commission’s path will be about 20% lower than emissions in 2019.
To justify gross-net comparisons, the commission pointed to the precedent set by the Kyoto Protocol, the predecessor to the Paris Agreement.
Justice Mallon said the commission made a deliberate decision to use a gross-net comparison, and explained it. “The commission did not make a serious logical error that led to an irrational recommendation.”
However, the advice was potentially misleading, she found, particularly for lay readers or anyone who did not read the full advice. “The Commission’s choice of a gross-net approach was to avoid being penalized for the cycles of trees already planted. This is an argument of fairness.”
However, this advice did not mislead the minister, the judge found.
Before the NDC was strengthened last year, the minister received additional advice from officials, including net-net comparisons.
Justice Mallon said the commission correctly interpreted the law. She agreed that the 1.5C target in the Zero Carbon Act is “more consistent with an aspiration rather than an obligation”.
The lawyers also criticized the commission’s chosen system of carbon accounting. Known as the NDC or an “activity-based” approach, it counts only some sources of emissions. Exactly what’s counted and excluded is still being decided.
The system was chosen because it smooths out the dips and peaks of plantation forests, the commission argued in court, and only counts permanent emissions reductions.
Lawyers for Climate Action argued that the commission should have used another accounting system, which better reflects the emissions that enter the atmosphere.
Mallon found lawmakers intended that the commission would provide advice on the most suitable accounting system. Therefore, it had the right to choose and use NDC accounting.
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