Climate change scientists accuse government of 'ignoring scientific evidence'

The prime minister has dismissed international climate scientists as "worthies" for criticising the government's approach to methane.

But the Green Party says New Zealand appears to be on a "climate denial bandwagon" and needs to end the speculation over what it plans to do about the country's single biggest source of emissions.

Christopher Luxon received a letter from 26 international climate change scientists accusing the government of "ignoring scientific evidence" over plans to lower its methane target.

New Zealand has one of the highest per-capita methane rates in the world because of its farming exports and the current target is reducing methane by between 24 and 47 percent by 2050.

Farmer lobby groups are demanding the government lower the target, and back away from any plans to put a price on methane.

Carbon dioxide - a slower acting but longer lived planet-heater than methane - has been priced in New Zealand since 2008.

Side-stepping advice from the independent Climate Change Commission, the government last year appointed its own scientific panel to tell it what level of cuts would be consistent with a goal of creating "no additional warming" from farming.

"No additional warming" is a concept approved by Federated Farmers and Beef + Lamb, but criticised by many climate scientists as a weak basis for climate action.

Adopting a target of "no added warming" would allow the farming sector, which produces more than half of New Zealand's emissions, to keep up its contribution to global heating at today's levels, indefinitely, regardless of new technology and farming methods promising to lower the impact.

The panel found cutting methane 14-24 per cent off 2017 levels by 2050 would achieve no added warming, but Cabinet has not said whether it will adopt that range as a target.

In the open letter, the scientists say aiming for "no additional warming" implied that current methane emissions levels were acceptable, when they were not.

It said the government's approach ignored the weight of evidence showing that methane had to reduce to get control of global heating, which saw 2024 again break heat records globally.

The letter says the government's path "creates the expectation that current high levels of methane emissions are allowed to continue [and] that it is acceptable to ignore emissions responsible for 30 percent of the current level of global warming".

It says this jeopardises New Zealand's climate commitments and its commitment to the Global Methane Pledge

Luxon came out swinging when asked about the criticism, which was prominently reported in UK business newspaper the Financial Times.

He said it was lovely there were "worthies" who wanted to send him letters, but academics "might want to direct their focus and their letters to other countries" because New Zealand was already managing methane emissions better than "every other country on the planet".

"I'll stack New Zealand's record up against any other country on the planet Earth around our methane emissions," said Luxon.

"We're not shutting down New Zealand to send production to other countries that are infinitely less carbon efficient."

Green Party co-leader Chloe Swarbrick said Luxon was missing the point, by confusing carbon efficiency with criticism of how the country was setting its future targets.

"It's really clear that Christopher Luxon has to end any further speculation that his government is on the climate denial bandwagon, they have wasted a year playing around with this mythical notion of 'no additional warming' and now international alarm bells are ringing," said Swarbrick.

"Obviously the Climate Commission has been really clear that any entertainment of "no additional warming" would mean households and business carrying an far higher burden and its time to draw a line in the sand."

Swarbrick said the government's approach posed huge risks for exports.

'Dangerous precedent'

Paul Behrens - a global professor of environmental change at Oxford University - was one of those who signed the letter.

In a statement supplied to RNZ he said: "Setting a "no additional warming" target is to say that the wildfires in America, drought in Africa, floods across Europe, bushfires in Australia, increasing food insecurity and disease, and much more to come are all fine and acceptable."

"The irony is that agriculture, one of the sectors most vulnerable to climate impacts, has many large, vested interests that resist and lobby against the very changes and just transitions needed to avoid those impacts," he said.

Another scientist behind the letter told the Financial Times that the New Zealand government's approach was an "accounting trick" designed to hide the impact of agriculture in countries with big farming sectors, namely Ireland and New Zealand.

Drew Schindel - a professor of climate science at Duke University in the US and chair of the 2021 UNEP Global Methane Assessment - said locking in heating from farming at today's levels would mean richer countries with big livestock sectors could avoid responsibility for reducing their climate impact, while poor countries with small animal herds would not be able to grow their farming sectors to produce more of their own meat and milk.

"The New Zealand government is setting a dangerous precedent," he said.

"Agriculture is the biggest source of methane from human activity - we can't afford for New Zealand or any other government to exempt it from climate action," he said.

Federated Farmers has said it will never accept the current target of reducing methane, while Beef + Lamb says its "bottom line" is reducing the target in line with causing "no additional warming."

But lowering the target would go against advice from the independent Climate Change Commission, which says reductions of 35-47 percent are needed for New Zealand to deliver on its commitments under the Paris Agreement. It says there are good reasons for New Zealand to raise the target but no basis to lower it.

Cabinet needs to respond to the commission's advice before the end of the year.

Both Swarbrick and Beef + Lamb say the ongoing delays in making a decision were a problem, with Beef + Lamb saying the delay was creating confusion and concern.

Climate Change Minister Simon Watts said Cabinet was still carefully considering the matter.

He said he did not take the letter's commentary to heart and "it doesn't stop the direction of travel we are following in undertaking a scientific review".

Watts said he remained happy with the context of the review and the expertise of the scientists the government selected to conduct it.

New Zealand has separate targets for methane and carbon dioxide, recognizing that methane is shorter lived. Carbon dioxide needs to fall much more steeply to net zero by 2050, affecting drivers, energy users and non agribusiness.

When Watts was asked which sectors of the economy would be asked to do more to cut emissions, if methane contributed less to the overall 2050 goal, he said no sector would necessarily need to do more, in contrast to what the Climate Change Commission has found.

Methane has caused most of New Zealand's contribution to heating so far, partly because it acts more quickly than carbon dioxide, front-loading the impact before it tails off.

Scientists - including the government's pick for prime minister's chief science adviser John Roche - expect methane-quashing drenches and other options to be available to farmers as soon as next year, and that consumers of dairy will be open to farmers using them.

But Federated Farmers and Beef + Lamb say farmers should not have to use new technology to reduce their climate impact.

Fonterra, meanwhile, is under pressure from its customers over its climate impact and is offering its dairy farmers cash incentives to achieve emissions goals.

The open letter is not the first time the government has been criticized for convening a panel to advise on a "no added warming" target.

The Parliamentary Commissioner for the Environment has dismissed the science review as a purely political exercise, saying that contrary to claims by the farming lobby, there was no new science on methane to justify a fresh review.

Upton also said there was no particular reason why farmers should get to 'keep' today's levels of heating, particularly given farming's climate impact is larger than it was in 1990.

A top Australian climate scientist told RNZ last year the government's goal was problematic.

Professor Mark Howden, Australasia's top representative on the Intergovernmental Panel on Climate Change, said taking a "sensible" mid-point from various IPCC pathways, methane would need to fall by roughly 60 per cent by 2050 to meet global climate goals, though not all of that reduction needed to come from agriculture.

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