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Environment
David Williams

Christopher Luxon and the art of offsets

Christopher Luxon wants to go beyond planting trees to explore methods of 'carbon capture' from the ocean. Photo: Supplied

Will the National Party leader push climate policy into the never-never, environment editor David Williams asks

Comment: Christopher Luxon has lately been talking about ram raids and boot camps for the worst young criminals. It seems solid ground for the National Party leader.

But I can’t stop thinking about his comments on climate policy earlier this month – not just for the substance, or lack of it, but for what this means for a future National-led Government.

This far out from an election, why is National making more noise about offsets than emission cuts? Under Luxon, might we see a re-tooling of public research funding from Labour’s pet project of hydrogen to carbon capture?

It was the week before the COP27 climate summit in Egypt. On Twitter, António Guterres, the United Nations secretary-general, warned: “It’s not too late to act on the climate crisis. Solutions exist. We must act now and scale up investments to reduce emissions and adapt to climate impacts.”

As Stuff reported, Luxon spoke at a meeting in Dannevirke, Manawatū-Whanganui, suggesting New Zealand could use its “huge area of ocean” as a way to “offset our carbon” emissions, simply by changing “the way we count it”.

Scientists scoffed. AUT senior lecturer Dr David Hall said proffering such an argument at COP27 would make New Zealand a “laughing stock”.

“The difference between forest removals and ocean removals is that humans can deliberately plant trees to sequester carbon, but we can’t ‘plant’ ocean.”

The following week, on RNZ’s Morning Report, Luxon was asked to explain.

National was keen to see carbon capture methods other than tree-planting, he said, to take pressure off farm conversions to forestry, and to protect food production.

The country needed to understand the sequestration benefits of carbon stored in oceans, he said, adding: “If I look at places like Australia ... there’s other things like carbon capture that’s happening, and those are other options where we actually need to be able to look at carbon capture methods beyond just trees.”

“We are not in control of this sink so it is hard to see how any country could claim responsibility for it.” – Melissa Bowen

However Luxon’s original comments have been explained, his basic premise was the ocean’s ability to absorb carbon and, through some accounting trick, magically using that as an offset for greenhouse gas emissions.

As my colleague Marc Daalder noted: “That’s not how international carbon accounting works – we only count man-made sinks and sources of emissions.”

A foundation of carbon accounting is “additionality”; the idea of doing something new.

So changing what is counted, or how it is counted, might make the accounting look better, but, crucially, it won’t change the amount of CO2 going into the atmosphere.

Dr Christopher Cornwall, a lecturer in Victoria University of Wellington’s Marine Biology School, says the oceans absorb between 33 percent and 66 percent of all CO2, depending on the study used, but generally it is recognised at about 50 percent.

Increasing the absorption of CO2 into oceans would be a huge problem, Cornwall says.

“CO2 reacts with seawater to form carbonic acid, resulting in reduced seawater pH – a process termed ocean acidification that Mr Luxon might not be aware of.

“Ocean acidification is projected to cause damage to our marine ecosystems in New Zealand by reducing the ability of biota with calcareous exoskeletons to form these calcium carbonate structures. Think pāua, kina, mussels, and the calcifying red seaweed that pāua and kina larvae depend on.”

Ocean acidification is also projected to have large impacts on coral reefs, halting their ability, in the face to storm surges, to act as centres of food and coastal protection.

“I am sure our Pacific nation brothers would be really happy that we think we could count increasing ocean acidification as a carbon offset. This would be an irresponsible act.”

Oceanographer Dr Melissa Bowen, a senior lecturer at University of Auckland, says via email a lot of carbon dioxide is absorbed at the latitude 50 degrees south, where cold water moves from the surface ocean to depth, taking dissolved CO2 with it.

“One of the major questions in climate is how this sink will change in the future. We have seen variability in the strength of this uptake over the past decades. We are not in control of this sink so it is hard to see how any country could claim responsibility for it.”

Highlighting complexity

The point of explaining this is not to put the boot into Luxon but, rather, to highlight the complexity of these natural systems.

A National Party spokesperson says the leader was actually talking about new technologies. As noted before, in subsequent radio and TV interviews he talked of methods of “carbon capture” beyond planting trees.

The idea of using our oceans as a carbon sink is attractive because of the huge swathes of land needed for afforestation to offset our emissions.

New technologies are now seen as essential because the promises by governments from around the world to cut emissions fall far short of limiting warming to 1.5C above pre-industrial levels, and even to keep warming below 2C.

In May last year, He Pou a Rangi, the Climate Change Commission, delivered its final advice to the Government. The report mentions so-called “blue carbon”, storing carbon in oceans and coastal marine habitats by, for example, growing seaweed, mangroves or seagrasses.

It was raised by several submitters, but the commission said the evidence is still developing, and robust accounting for ocean sinks is not yet possible.

“More work needs to be done on the scale and permanence of these emissions and removals and how they could be accounted for before they could be included in emissions budgets.”

(In 2018, research into blue carbon by Dr Wendy Nelson, of Crown science agency NIWA, was recognised internationally. She co-authored a paper exploring the potential of commercial seaweed farming to mitigate global carbon dioxide levels.)

The latest assessment report from the Intergovernmental Panel on Climate Change discusses various methods of carbon dioxide removal, or direct air carbon dioxide capture and storage.

It’s noted, however: “All mitigation strategies face implementation challenges, including technology risks, scaling, and costs.”

In other words, they’re unproven, untested, and, quite possibly, unaffordable. Their efficacy is uncertain.

One of the big unanswered questions posed in this piece in science website The Conversation is: could they store enough carbon anyway?

What if carbon-absorbing kelp forests are eaten by sea creatures, or carbon in the atmosphere lasts longer than commercially grown seaweed?

There might also be unwanted side-effects on the marine environment from methods such as ocean fertilisation, used to stimulate the growth of phytoplankton.

Associate Professor Sonja Klinsky, of Arizona State University, and Professor Terre Satterfield, of the University of British Columbia, wrote in The Conversation there are “a variety of ethical questions that do not have straightforward answers”.

They conclude: “Ocean carbon dioxide removal could become a useful method for keeping global warming in check, but it should not be seen as a silver bullet, especially since there isn’t an effective global system for making decisions about the ocean.”

Luxon’s statement in full

We asked several questions of the National Party. They included:

  • What methods of carbon capture is Luxon advocating?
  • Is he saying New Zealand should move away from tree planting in favour of these other methods, or continue to plant trees to a lesser degree?
  • What is National’s policy on carbon capture and storage underground?
  • From where or whom is he getting his climate advice?

Here is Luxon’s emailed statement in full:

“National is committed to New Zealand’s emissions targets including net zero by 2050.

“We’re advocating for successful delivery of emissions targets and that requires effective solutions. We would like to see other carbon capture and storage technologies come into the ETS.

“Technologies must be scientifically robust to come into the ETS, and only additional or human-induced carbon capture should be recognised.

“Every option should be on the table because that gives this country the best chance of success.

“As you would expect on this important issue, we speak to many people working in this area.

“We do not have a position on carbon capture and storage itself. However, we support recognition of other carbon capture and storage technologies besides trees, again provided they are robust and additional.”

Recognition of “additional or human-induced carbon capture” shows National has learnt a lesson from this episode.

It’s important to know National is committed to net zero by 2050. However, being committed isn’t the same thing as having a plan to get there. The science says deep and drastic cuts to emissions are needed immediately to limit dangerous warming, so if there’s a departure from that it should explain why.

Another question is: which emissions targets will Luxon and his party deliver? Will it scrap or tinker with existing policy, such as Labour’s 2030 target?

Also, without full transparency how will the public know if National is adopting policies favoured, or paid for, by fossil fuel interests, who have a vested interest in the status quo?

Fundamentally, tackling the climate crisis means reducing emissions.

The art of the offset for countries not taking the climate crisis seriously is spending millions on research while continuing to pollute.

The public shouldn’t be fooled. There’s no substitute for immediate action.

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