Open letter: Aotearoa New Zealand needs climate policy that addresses our unique challenges

Our climate change policies are inadequate and will limit our ability to make any meaningful difference for mitigating climate change. The national climate narrative is fixated on primary production and specifically farming. In assessing the climate impact of farming, carbon dioxide, nitrous oxide and methane emissions are the main focus. This sets the scene for targeted levies based on greenhouse gas (GHG) sources. The only on-farm greenhouse gas sinks considered are forests and vegetation that meet certain mitigating criteria; and now the Climate Change Commission is recommending that those sinks are not allowed.[i] Soil and pasture have been dismissed as sinks that sequester[ii] or neutralise different GHGs even though soil contains larger stocks of carbon than the atmosphere and vegetation combined.[iii], [iv]

Distracted by a simplistic framing of the problem, we are diverted from solutions that would provide much more leverage to mitigate climate change. This position negates our ability to achieve Net Zero Values for carbon or any of the GHGs, if we are unable[v],[vi] or unwilling to accurately monitor (or prescribe levies for) existing emission levels.

According to the IPCC, 87% or more of methane is recycled by hydroxyl radicals[vii], induced in abundance in Aotearoa New Zealand by water vapour and volatile organic compounds[viii] (VOCs), released from growing vegetation. Yet this sink is completely ignored.

Aotearoa New Zealand has high levels of photosynthesis year-round because of its soils, temperate climate and lush vegetation. This draws down carbon, generates the water vapour that is the raw material for hydroxyl radical production, and directly cools our environment by the transfer of latent heat higher into the atmosphere. This transfer, back into the atmosphere by transpiration-driven cooling, deflects the sun’s radiant energy away from the harder surfaces thus mitigating thermal emissions. This natural bounty we are blessed with provides our main agency, alongside eliminating fossil fuels, to moderate the climate. This video[ix] provides further explanation of the dynamics of water in climate mitigation.[x] 

If these sinks – soil carbon and hydroxyl radicals – were included in carbon budgets, many farms in Aotearoa New Zealand would be in carbon credit. Finding mechanisms to include reduced heat emissions through the agency of photosynthesis and transpiration would further improve their position. We would then be evaluating farms on net emissions rather than gross emissions.

Our relatively large population of ruminants positions methane as our major GHG. In particular, our solutions must be tailored to this unique context. This means positioning pastoral/animal derived methane in a separate compartment from industrial methane, which may be impacted minimally by atmospheric cleansing plant-based hydroxyl radicals produced by pastures and forests. Recent attribution of increasing levels of atmospheric methane has been unfairly linked to anthropogenic emissions from agriculture[xi] when recent molecular typing (13CH4) proves that increases in methane are more likely linked with rogue emissions from unsealed oil or gas wells associated with shale gas extraction and fracking.[xii]

In addition, primary production remains the mainstay of our economy, recently crossing, for the first time, the threshold of $50 billion in export revenue. How perverse that we seek to unfairly hobble the potential of these industries that generate such resources to mitigate and adapt to climate change. Cities are recognised as urban heat islands, often two degrees centigrade warmer than the countryside and sometimes significantly more. Manufacturing and business activity that happens in cities will struggle to achieve sustainability. Yet primary producers can go way beyond sustainability to regenerate ecosystems, while still growing our food. The problem is not farming itself, but the level of intensification. The solution is the rapid and widespread development of practices that accelerate development of greenhouse gas sinks while fostering greater biodiversity and ecosystem regeneration. This remediates the climate and sustainably produces the food people need.It is consistent with the values embodied in kaitiakitanga.

It is bewildering that agricultural industry bodies have so meekly capitulated to a flawed climate narrative. Some gaze at a distant horizon looking for high risk technological silver bullets, while ignoring nature’s capability to sustain balance, if only we would work alongside her. Creating policy that recognises both GHG sources and sinks resonates with the more holistic view of biology and earth systems inherent in mātauranga Māori. We need climate policy that is fair to all people in Aotearoa New Zealand, while it continues to focus on climate remediation.

It is time to widen the debate moving away from inorganic chemical-driven industrial farming practices with high external inputs to biologically-based regenerative practices with proven abilities to build greenhouse gas sinks. The climate, ecosystems, biodiversity, human health and our economy will benefit. Now that is a silver bullet!

In climate change we face an unprecedented existential crisis. If we want our children and grandchildren to enjoy a good life on this planet, we need to re-examine the assumptions that guide present action in the light of emerging understandings. We, the undersigned, ask you to foster the public debate on this important issue.


1. Support research into the efficacy of soil carbon and hydroxyl radicals as sinks and transpiration-driven cooling to moderate the climate.

We applaud the Government’s recent increases in climate change research. As with the public narrative, research resources are too focused on technological fixes and ignore the biological cycling perfected by nature. Irrespective of the proportional contribution New Zealand can make to climate remediation, because of our small size, we can provide leadership in providing biological solutions that will position us as world-leading producers of quality foods, with net Zero Carbon emissions.

2. Advance the global debate on GHG sinks (including carbon sequestration in soil, and hydroxyl radicals) and transpiration-driven cooling. 

Given that current understandings of methane are very significant for Aotearoa, it is vital that we seek out those globally who share the signatories’ perspective of the need to advance the narrative. An example is the planned establishment of a multi-million dollar Indo-German Research Centre in Andhra Pradesh, India, to advance agroecology and reverse desertification of wastelands, increase water storage, retain topsoil and prevent soil erosion.

3. Impose graduated levies on artificial fertilisers.

We support the intention recommended by the Climate Change Commission to introduce graduated levies on synthetic fertilisers, especially urea. A Full Life Cycle Analysis must be carried out to quantify the manifest effects of synthetic nitrogen fertiliser on soil health and nitrous oxide emissions.

4. Identify barriers and enablers for more rapid learning to enable us to moderate the climate.

The current nexus between policy development, science, and the profit motive inhibits our learning. The antidote is greater transparency in how research funding is allocated and decisions are made. We encourage the Government to foster a reflexive research culture that takes full advantage of emerging understandings and transcends the limitations of the current siloed approach to research.

Emeritus Professor Frank Griffin (ONZM, FRSNZ) Director Ag@Otago, University of Otago Bruce-Iri Independent Researcher
Alfred Harris Scientist (structural biology)Max Purnell Farmer
Millan Ruka (MNZM) Kaitiaki and River AssessorMarcus Williams Director of Research and Enterprise, Unitec
Sir Alan Francis Mark (KNZM, CBE, FRSNZ) Botanist & Environmentalist University of OtagoGraham Shepherd Soil Scientist, Agricultural Advisor and author of the FAO Visual Soil Analysis
Wendy Bown Environmental Film MakerGlenn Edney Ocean Ecologist
Fiona Douglas Executive and Organisational CoachTrish Allen Retired Organic Farmer
Janette Perrett Dairy farmer & Chair of Organic Dairy & Pastoral Group of New ZealandRichard Bentley, Freelance Writer specialising in sustainable agriculture and related science and technology.
Anna Harding Farmer, DargavilleUrsula, Erwin, and Shani Eisenmann Waima Hill Organic Beef
Callum Lane Lane Family FarmSam Hogg Mingiroa Farm
Steve Erikson Chaos Springs FarmJohn King Holistic Management Educator
Professor Craig Bunt Inaugural Professor in Agricultural Innovation Director Agricultural Innovation Programme University of OtagoDr Sebastian Gehricke Senior Lecturer, Otago Business School Deputy Director, Climate and Energy Finance Group, University of Otago
Align Farm Group, Ashburton Dairy Consortium (6 farms)             Impact Investor: John Buchanan CEO: Rhys Roberts Environmental Management: Clare BuchananAssociate Professor Janice Lord. Botany Department, University of Otago Indigenous and Exotic Forestry Carbon Sequestration  
Allan Richardson Avalon Farms, West Otago Organic and Regenerative Farming Board member of Organics AotearoaHamish and Amy Bielski Rehoboth Farm Regenerative Farming, Beef & Lamb
Mark and Madeline Anderson, Westridge Dairy Farm, Clinton Holistic Annual GrazingAndy Barratt Organic/Holistic farmer
Dylan & Sheree Ditchfield Ditchfield Group Dairy Farming and Business LeadershipSiobhan Griffin Farm Consultant, Next Level Grazing
Phyllis Tichinin True Health Ltd.Jono Frew Managing Director, Natural Performance Ltd.
Wayne Douglas Regenerative farmer and educatorTracy and Fred Ody Ody Farm
Rhodes Donald Director, Polson Higgs Wealth Management 
International signatories 
Professor John Elkington Author and Founder & Chief Pollinator, VolansProfessor Peter Head CBE Founder and Chair, Resilience Brokers
Dr Christine Jones Independent ResearcherWalter Jehne Director, Regenerate Earth
T. Vijay Kumar
Executive Vice Chairman Rythu Sadhikara Samstha
William Becker Author and Executive Director, Presidential Climate Action Project
Professor Peter Byck Film maker and academicJon Schull
Co-founder of EcoRestoration Alliance
Judith D. Schwartz Environmental Journalist, USAGerry Gillespie Founding member – Zero Waste International Trust

[i] Climate Change Commission, ‘Farmers Could Be Ready for “basic” Emissions Pricing by 1 January 2025’, He Pou a Rangi: Climate Change Commission, 6 July 2022,

[ii] Elena Di Federico, ‘Sequestering Carbon in Soil and Retaining Soil Carbon Stores – Orientations for CAP Strategic Plans’, Text, 16 January 2020,

[iii] R. Lal, ‘Soil Carbon Sequestration Impacts on Global Climate Change and Food Security’, Science (New York, N.Y.) 304, no. 5677 (11 June 2004): 1623–27,

[iv] Sam R. McNally et al., ‘Soil Carbon Sequestration Potential of Permanent Pasture and Continuous Cropping Soils in New Zealand’, Global Change Biology 23, no. 11 (2017): 4544–55,

[v] Dave S. Reay et al., ‘Methane and Global Environmental Change’, SSRN Scholarly Paper (Rochester, NY, 1 October 2018),

[vi] Chao Liang et al., ‘Quantitative Assessment of Microbial Necromass Contribution to Soil Organic Matter’, Global Change Biology 25, no. 11 (2019): 3578–90,

[vii] IPCC, ‘IPCC Fourth Assessment Report: Climate Change 2007’, IPPC, 2007,

[viii] Michael S. Waring and J. Raymond Wells, ‘Volatile Organic Compound Conversion by Ozone, Hydroxyl Radicals, and Nitrate Radicals in Residential Indoor Air: Magnitudes and Impacts of Oxidant Sources’, Atmospheric Environment 106 (1 April 2015): 382–91,

[ix] Climate Change: The Water Paradigm – YouTube, 2020,

[x] Tina Perinotto, ‘The Power of Water to Cool the Earth Is Bigger than We Think’, The Fifth Estate, 7 November 2017,

[xi] Frank Mitloehner, ‘Why Methane from Cattle Warms the Climate Differently than CO2 from Fossil Fuels’, CLEAR Center UC Davis, 7 July 2020,

[xii] Robert W. Howarth, ‘Ideas and Perspectives: Is Shale Gas a Major Driver of Recent Increase in Global Atmospheric Methane?’, Biogeosciences 16, no. 15 (14 August 2019): 3033–46,

2 thoughts on “Open letter: Aotearoa New Zealand needs climate policy that addresses our unique challenges

  1. Kia Ora Peter,

    Yes, excellent, i couldn’t agree more with the content and intent of your group letter. Well done to the collective for setting it out clearly and for the initiative. Please add my name to your list if desired, using the label ‘ecologist and regenerative farmer’.

    Let’s hope that it may help to shift the narrative towards more useful climate change remedies for NZ.

    The fact that we are stuck on the ‘blame the farmer’ narrative is so obviously political scapegoating, farming being an easier target compared to the oil industry lobby. But also the industry has left itself wide open to this kind of attack by being stuck in the 20th century ‘oil age’ model of farming of high industrial inputs, and not moving with the times to a low input, soil orientated approach. Unfortunately it also conflates the perfectly reasonable charge of loss of biodiversity and damage to our rivers, that has been very slow to gather momentum in NZ, and is only now being tackled alongside the climate change debate.

    I am currently in UK where there is an acknowledgment and understanding that peat bogs are important carbon sinks and they are being protected and restored on that basis. They are also bringing in policy for biodiversity payments to farmers and farmers to be required to increase biodiversity, all of which is helpful for pushing things in a better direction. However, the underlying hydrology and soil dynamics still seem poorly understood. Fortunately they’re not so hung up on methane from livestock sources as we are in NZ for remediating their GHG emissions.

    One excellent initiative here, which is quickly gathering traction as a flood alleviation tool more than anything, is the use of ‘rewilding’ beavers as ecosystem engineers to recreate wetlands and rehydrate the landscape. This is very exciting landscape-scale stuff. Unfortunately I don’t think we’d get far with it in NZ as we don’t have an equivalent previously native aquatic creature to turn to! Regenerative farming itself is also much more accepted as mainstream farming model here too, with many large estates and also big arable farmers onboard, & also with many outlets for local and environmentally-grown branded foods.

    I think to gain any traction in NZ to shift the narrative we have to provide policy recommendations to drive change and I would certainly applaud the suggestion of applying levies on fertilizer. Personally I wouldn’t shy away from recommending a farmer incentive scheme either with payments to drive change, as well as a review of the monopolization of the processing chain and lack of access for small players, preventing diversification of retail opportunities for farmer & growers. We need this broken open as we are just starting to see happen in the duopoly stranglehold of the supermarket food retail operation.



  2. Much of the current thrust of policies to do with carbon and climate around the world is framed around negativity. Sanctions, levies, shaming and ill considered government intervention are creating a toxic soup of regulations that will increase world poverty, increase inequality, decrease food security, hurt public health and do little to decrease levels of greenhouse gases in the environment.
    I’m encouraged by Peter’s positive approach to finding solutions that address the removal of pollutants from the environment while continuing to sustain life for the people on the land and those they feed. In our own case by following carbon positive farming principles we have been able to sequester a significant amount of carbon in our soils.
    I hope that as time goes by more people will come on board with a vision for making positive contribution to a better world, who knows, maybe even politicians.


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