Scientists fear the Government's decision to weaken New Zealand's methane reduction target signals a broader retreat from climate action — including an intent to back away from our international commitments, and ultimately cause more warming.
The coalition confirmed yesterday it would cut the 2050 target for biogenic methane — mostly from agriculture — from a 24-47% reduction below 2017 levels to just 14-24%.
It also ruled out any future methane levy or tax, delayed by two years its required response to the Climate Change Commission's advice to strengthen climate targets, and said the changes would be pushed through under urgency within two months.
While the farming industry responded positively to the news, many climate scientists condemned the move as an unprecedented rollback that would increase global warming and undermine New Zealand's credibility.
Christina Hood, an independent climate change and energy policy expert at Compass Climate, said she feared the decision signalled an intent by the Government to weaken the rest of New Zealand's climate targets.
That would mean not only more methane in the atmosphere than previously promised, but more CO2, which would mean more damage to the planet.
"If we weaken our targets, we will cause more warming," Hood said. "I don't think that that's an okay thing to be doing given the state of climate emergency that we see in the world."
'Tripling all our other emissions'
The Climate Change Commission previously warned the Government the consequence of adopting the weaker methane target would mean New Zealand either had to accept more warming, contradicting its obligations under the Paris Agreement; or force steeper CO2 cuts elsewhere — like in energy or transport — to offset the extra methane.
The Commission's analysis showed how large the burden from cutting the methane target would be.
For every one-percentage-point reduction in methane ambition, New Zealand would need to offset 36-44 million tonnes of CO2-equivalent elsewhere — about a year's worth of the country's total emissions.
A drop of 16% equates to more than 600 million tonnes of extra CO2-equivalent that would need to be removed or offset to keep the same warming outcome — a cost of up to $130 billion in international carbon-credit purchases.
The Parliamentary Commissioner for the Environment has estimated the change would also require about 1.5 million hectares of new pine forest to offset — nearly 6% of the country's total land area.
Hood said the scale of warming created by the weaker methane target was so enormous it was almost impossible to compensate for.
"The extra warming caused by weakening the methane target is massive: it is roughly equivalent to tripling all of our other emissions out to 2050," Hood said.
"If we were to try and compensate by reducing other gases quicker, we'd need to be net-zero for other gases immediately and be net-negative to pull back all our CO₂ emissions since the Paris Agreement was signed out of the atmosphere."
Professor Ralph Sims of Massey University said the Government had scrapped many of the policies needed to make up the difference.
"If methane is not reduced in New Zealand, then we've got to reduce something else — and that means all the things the current government has thrown out, like support for electric vehicles, the GIDI scheme for decarbonising industry, and moves away from gas and coal," he said.
"We're going backwards. And the farming community are the ones who are going to be impacted as much as anybody — probably more — because of droughts, floods and the impacts on their crops, cattle and pasture. It's not a good scene at the moment."
'Completely incoherent'
Under the Climate Change Response Act, the Government must set five-yearly emissions budgets that cap total greenhouse-gas output across the economy.
They rely on advice from the Climate Change Commission to decide what cuts to make — the commission's latest advice was to strengthen the targets.
The second budget (2026-2030) is due to be updated this year, but ministers have now said they will wait until 2026 — two years later than required — to respond to the commission's advice.
Distinguished Professor Robert McLachlan of Massey University said together, the methane decision and the delay on emissions budgets amounted to "a significant assault" on the environment, on the integrity of the Climate Change Response Act and on New Zealand's contribution to global climate goals.
"It makes a mockery of the Act's purpose to 'contribute to the global effort under the Paris Agreement to limit the global average temperature increase to 1.5 Celsius above pre-industrial levels'."
He accused the Government of "double speak".
"They're trying to say two things at once — that they are following the Climate Change Act and that it's important for farmers and trade, but at the same time, they're just doing one assault on the climate after another," McLachlan said.
While the Government continued to say it will still meet New Zealand's Nationally Determined Contribution under the Paris Agreement — a 50% cut by 2030 — McLachlan said it had no credible plan.
"It's all just extend and pretend. It's completely incoherent."
The scientists also warned that it could expose New Zealand to reputational and commercial risks, particularly as the European Union begins enforcing climate provisions in its trade deals.
The EU-NZ Free Trade Agreement includes the obligation to "refrain from any action or omission that materially defeats the object and purpose of the Paris Agreement" and includes the provision that parties may take "appropriate measures" in the event of such acts or omissions.
Professor James Renwick, from Victoria University of Wellington, said the Government's approach "in no way" represented New Zealand's highest possible ambition as laid out in Article 4 of the Paris Agreement.
"Our trading partners are unlikely to smile on this reduction in ambition," he said.
The new methane target
New Zealand's climate targets are enshrined in law by the Climate Change Response Act in 2019. To reflect the different ways the greenhouse gases behave, there are separate targets for methane, and carbon dioxide, or CO2.
Methane is more potent, but breaks down faster, while CO2 stays in the atmosphere for centuries, meaning even the strongest emissions reduction efforts can only stabilise its heating effect at today's levels.
The new methane target reflects a controversial idea known as "no additional warming" — the notion that it is enough for methane's warming impact to remain roughly flat at current levels rather than fall sharply.
That approach, first promoted by industry groups and later adopted by the Government's independent methane review panel, was rejected outright by the Climate Change Commission in its 2024 advice.
The commission warned that adopting the principle would either mean more overall warming or would require steeper, costlier cuts in carbon dioxide and other gases to compensate.
"A 'no additional warming' principle does not give a clear answer to target-setting based on science," the commission wrote.
"[We] have found no reasons to relax Aotearoa New Zealand's contribution to global efforts, and no significant change that would justify causing even more warming than under the current target."
The Government says the lower target will provide exporters with a clear pathway to reduce emissions while maintaining productivity and trade competitiveness.
Agriculture, Trade and Investment Minister Todd McClay said the Government had worked closely with industry and accepted a range of advice to determine a "practical target".
The Government has not responded to questions about how it will make up the shortfall in the emissions budgets, given the lower methane target.
On Sunday, Climate Change Minister Simon Watts said the Government remained committed to New Zealand's climate change commitments, "including net zero by 2050.
"Agriculture will continue [to] make an important and fair contribution to achieving this reduction," he said.
By Kirsty Johnston of rnz.co.nz
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