Govt sidelines Climate Commission in seeking do-over of advice

Analysis: On Monday evening, the Climate Change Commission is set to release three important pieces of draft advice on the targets New Zealand should set for cutting climate pollution.

It will have been something of a surprise to the staff who have worked on these documents for more than a year when the Government on Saturday announced it was effectively seeking to have some of that work repeated, before the results had even been publicly released.

One of the three documents slated for release on Monday is the first five-yearly review of New Zealand’s 2050 net zero target and 2030 and 2050 methane targets. But Climate Change Minister Simon Watts and Agriculture Minister Todd McClay undercut the influence of that advice by announcing a separate review of the methane targets, with independent experts to be appointed by ministers “in the coming months”.

Of course, the commission is already an independent body. Its creation was supported by two of the three parties making up the coalition Government and the Prime Minister went to great pains during the campaign to emphasise its importance in National’s approach to climate policy.

At issue is how steeply – or perhaps even whether – emissions from livestock should be slashed over the next few decades. Currently, New Zealand has set a target for a 10 percent reduction by the end of the decade and cuts of 24 to 47 percent by 2050, from 2017 levels.

Methane is treated differently under New Zealand’s climate policies than other greenhouse gases. That’s because its warming effect is relatively short-lived – only a couple of decades.

While it’s up there, it has a significant heating effect, but that is time-limited. If methane emissions grow, warming increases rapidly. If they decline very slightly (around 0.3 percent per year, according to the Intergovernmental Panel on Climate Change), warming stops. If they fall further, warming plummets – ie, the world cools rapidly.

Other greenhouse gases, like carbon dioxide and nitrous oxide, remain in the atmosphere for hundreds or thousands of years. Constant emissions of CO2 mean the world will keep warming at a constant rate. As emissions fall, the rate of warming will fall. If they hit net zero (emissions fully balanced by absorbing carbon through trees or mechanical measures), warming stops completely. If we begin to absorb more than we’re emitting, the world will start getting less warm – that is, it will cool.

This is why New Zealand has set much steeper targets for the carbon economy (primarily industry and the urban environment) than the methane economy (agriculture).

The Climate Change Commission is already required to undertake regular reviews of New Zealand’s targets, including the goals for methane. It can only recommend a change under a narrow set of circumstances, such as if there has been a significant change in scientific evidence since the original targets were set.

By announcing a separate review, the Government is undermining the commission in one of two ways.

The most generous interpretation would be that it does not trust the commission to correctly assess the state of the science. If the Government has lost faith in the commission’s ability to provide proper advice, that would necessitate a separate review, but it would presumably go much further than just methane. The Government has also not made any public statements that would suggest this is its view – in announcing the review, Watts said it would “complement” the commission’s work.

The alternative interpretation is less generous to the Government’s motivations. This understanding posits that the review is seeking a predetermined outcome that the Government doesn’t believe the commission will deliver: A recommendation to weaken the methane targets.

A hint that this latter interpretation is the Government’s true motive is available in the thin detail provided so far about the review. McClay said the review “will provide evidence-based advice on what our domestic 2050 methane target should be, consistent with the principle of no additional warming”.

The principle of no additional warming is based on methane’s short-lived nature. It suggests that targets should be set based on what would be required to halt methane’s mounting contribution to warming. That principle is not included in the Zero Carbon Act and is a political choice, not a scientific one.

Choosing to reconsider the methane targets in light of this principle has several flow-on implications. First, such an approach would effectively “lock in” all of the warming New Zealand’s methane has caused to-date, since agriculture would only be asked to make reductions sufficient to flatline that contribution to warming.

Given that methane is already responsible for 70 percent of New Zealand’s overall contribution to global warming, that’s a big step. The old approach would have seen methane reductions contribute to “cooling” the world, the new one suggests New Zealand’s responsibility is only to stop the problem from getting any worse rather than trying to make up for the damage we’ve already done.

It’s also different to how carbon dioxide and other greenhouse gases will be treated. While in the near-term, CO2 emissions will continue to add to global warming, the Climate Change Commission expects us to reach net zero carbon in the late 2030s. After that, New Zealand could move net-negative, sequestering more carbon than it emits and helping “cool” the atmosphere. Under the Government’s novel approach to methane, this would see the carbon economy doing the heavy lifting of undoing climate change even though the methane economy is responsible for the bulk of New Zealand’s contribution to the problem.

There is also still some uncertainty about exactly what “no additional warming”-consistent targets might entail.

Last year, farming groups Dairy NZ, Beef + Lamb and Federated Farmers submitted research they had commissioned on the methane targets for the Climate Change Commission’s consideration as it undertook its review. They also publicly released this information, claiming it included new scientific knowledge that meant the targets should be reconsidered from a “no additional warming” perspective.

In an unusual move, the Parliamentary Commissioner for the Environment Simon Upton pushed back, releasing a letter to the three groups and the Climate Change Commission which disputes the research being new.

“This study appears to be more or less a repeat of the modelling exercise I commissioned and summarised in my 2018 note on New Zealand’s methane emissions from livestock,” he wrote.

While there are slight methodological changes between the studies, they produced very similar results of what level of methane reductions would be consistent with contributing to no additional warming from agriculture beyond what has already occurred.

Those estimates are generally more lenient for 2050 than the targets currently in law. However, they are much more ambitious in the near-term. In a scenario where the world acts to keep warming below 2C, for example, Upton’s modelling showed a 20 percent cut by 2030 would be needed – double the ambition of the current target. If the world is successful at limiting warming to 1.5C, even steeper reductions are needed.

There’s another figure floating around as well – the maths from the Intergovernmental Panel on Climate Change. That suggests that global reductions of methane on the order of 0.3 percent per year would halt any contribution to warming, but that’s a simplistic figure that doesn’t necessarily scale down to the New Zealand situation like Upton’s work did. It is, however, a figure cited repeatedly by governing parties over the past few years.

If it were adopted, the ambition of New Zealand’s methane targets would more than halve, to a 3.3 percent reduction by 2030 and a 10 percent cut by 2050.

By launching this review, the Government has set the stage for the next big battle over farming’s climate pollution. There is a clear – and in some cases explicitly stated – preference by ministers that the methane targets should be watered down. The review lays the groundwork for doing so while using science as cover for what is ultimately a political decision, as there is no new scientific information which has significantly changed our understanding of methane’s warming impact.

While a scheme to make farmers pay for their climate pollution is dead in the near-term, the obligation for them to still slash their pollution currently lives on. The next big debate in this space will be over how much those emissions should fall by and why.