Susan Harris says fossil fuel emissions cause dangerous climate change, not cows and sheep

By Susan Harris*

Under the Paris Climate Agreement, New Zealand's Second Emissions Reduction Plan 2026-2030 has biogenic (livestock) methane emission targets of 24 -47% reduction below 2017 levels by 2050, and a 10% reduction below 2017 levels by 2030. Very major changes in farming practices are needed to reach these targets.

Since 2009 New Zealand has spent $339 million into research on reducing livestock methane emissions, and the Government recently dedicated $155 million more, when at a global level any emission reductions achieved will be quickly cancelled out by much larger and increasing fossil fuel-sourced methane emissions.

It is critically important to understand that the correct assessment of the effects of greenhouse gas emissions is at the global level, not the national level. This is because what is released in New Zealand or anywhere else mixes in the atmosphere, travels around the world, and affects the entire planet.

When designing livestock emission reduction research, the impacts of other methane sources must be considered to ensure that what can be practically achieved with livestock will actually result in a net global reduction in methane emissions. All Nationally Determined Contributions (NDC) to the Paris Climate Agreement should be framed this way so that permanent, not pyrrhic emission reductions are achieved by those primarily responsible for them.

Fossil fuel methane emissions under-reported by 80%

It has been confirmed that fossil fuel methane emissions have been under-reported by 80% for decades (IEA 2025). Observations of under-reporting started to appear in research articles from 1996 in a local situation (Scheff P A et al 1999 ; and in 1999 at a national level (Subak S 1999, Science Direct). A recent update is here at Cenci and Biffis 2025.

If we add 80% more methane emissions to total energy emissions reported in 2023 we see that they exceeded those of agriculture by 110% (Figure 2 below, 2023 Adjusted). This fact totally confounded any efforts by the agriculture industry to reduce global emissions of methane in 2023.

Add 10% more net emissions for agriculture (increasing food demand), and a further 56% growth in energy emissions to 2034 (Figure 2), we see that fossil fuel methane emissions will exceed livestock emissions by 150% in future, thoroughly cancelling out any livestock emission reductions achieved anywhere in the world. Thus, attempts to reduce livestock emissions may be heroic, but are ultimately futile.

The International Energy Agency has been documenting under-reporting of methane emissions, and in its latest 2025 report, it notes that:

"Around 70% of methane emissions from the fossil fuel sector could be avoided with existing technologies, often at a low cost....The agriculture and waste sectors are also major sources of methane emissions, but fossil fuel supply offers the greatest potential for immediate reductions in methane emissions. Solutions that lower methane emissions from fossil fuels to near zero already exist, and they could be deployed today at little – or even negative – cost."

Simple house-keeping by the fossil-fuel industry could reduce their methane emissions by 70%, or 84 million tonnes per year (2025 figures). They could even make a dollar out of it by being more efficient (IEA 2025 Global Methane Tracker). And it wouldn't cost farmers or taxpayers a cent.

Natural emissions from livestock since 12,000 years ago never affected climate

Going back a bit, agriculture began to develop during the Neolithic Revolution around 12,000 years ago. Livestock were around long before fossil fuels were discovered, and lived within the natural environment for 12 millennia without their natural emissions causing any dangerous climate change. With the growing world population and the expanse of human civilisation, livestock numbers increased and they became the primary source of food protein for the world and the foundation of the New Zealand economy.

Livestock methane emissions have increased about 8.5-fold (from a very small initial amount) as livestock numbers grew to feed the increasing world population.

Rocketing fossil fuel emissions over past 175 years

There is a spectacularly different picture for fossil fuels. Widespread use of coal, oil and gas grew rapidly during the Industrial Revolution from the 1850's onwards. The first public observation in New Zealand that this could alter climate was expressed in the Rodney and Otamatea Times on 14 August 1912 by an unknown author.

The article was prophetic. Since 1850 there has been a 13-fold jump in emissions from fossil fuels, far outweighing increases in emissions from livestock; and a 1.5°C increase in global temperature. An assessment by the European Union in 2024 shows that agriculture (all types) contributes about 12% of global emissions, fossil fuels 87%.

Antarctica - the gigantic bellwether of dangerous climate change

The Arctic and Antarctic have been described as the two "anchors" of climate on Earth. Sea ice follows a pattern of melting in summer and refreezing in winter. Because of warming waters and a warming atmosphere, the Arctic is now ice-free in the summer, so one anchor is away.

Antarctica is the fifth-largest continent. It is about 1.5 times the size of the United States and nearly twice the size of Australia. It holds 90% of all freshwater on Earth in 30 million cubic metres of ice (2020 reference).

Sea ice measurements in Antarctica began in 1978. From 2016 onwards, Antarctic sea ice entered a new 'low-extent" regime, where large areas of ice did not refreeze and more large icebergs calved off the continent. East Antarctica started melting first, and then from 2022 the much larger West Antarctica icesheet started breaking up (Doddridge, E. et al 2025). Livestock populations have not rocketed up sufficiently since 1978 to drive this melting, but fossil fuel-sourced emissions have.

Fossil fuel emissions (all greenhouse gases) are five to seven times that of livestock emissions. Even if all agriculture on Earth stopped, there would still be a climate change problem. Huge pieces of Antarctica are not falling off because of relatively small levels of methane emissions from cows and sheep.

New Zealand disadvantaged by a "false negative" emissions profile

Livestock emissions would not be an issue for New Zealand if it did not have a unique emissions profile dominated by agricultural emissions at 53% of the total (2024 data). Most developed countries have a profile dominated by energy emissions from fossil fuels. Because New Zealand has already decarbonised its energy production with 85% of it coming from renewable electricity, a "false negative" is created that makes the country appear to be a climate laggard.

Ironically, New Zealand is being penalised for its global leadership in clean energy in an agriculture-based economy. Other nations can "look better" than New Zealand if they decarbonise their fossil fuel dominated energy production and claim this as an achievement, when New Zealand has already mostly decarbonised its energy production.

Nevertheless, New Zealand and other agriculturally-based countries have been under pressure to reduce livestock emissions as part of their Paris Climate Agreement commitments. Research on agricultural greenhouse gas emissions began in New Zealand in 2007, with New Zealand leading the formation of the Global Research Alliance on Agricultural Greenhouse Gases in 2009. The GRA has 68 countries and 20 partners contributing to over 90 research projects.

Research efforts include developing feed additives, breeding low-emitting animals, improved feed efficiency, methane-reducing vaccination and methane inhibitors that reduce the production of methane in the animals' multi-stomach digestive systems. Notably in 2024 the GRA promoted a research call to reduce greenhouse gas emissions from ruminant (cows, sheep, goats etc) digestion systems, which are incredibly complex. The further $155 million in funding over the next five years is targeted at the reduction of livestock emissions. So far, research results project an expected 10% reduction in livestock emissions at some time in the future.

None of this appears to have been considered in the global context of methane emissions from multiple sources, which are the most dangerous, and which are the most effective and cheapest to reduce.

Academics wrongly chastise New Zealand Prime Minister on livestock methane emissions policy

Remarkably, the academic authors of the June 2025 Open Letter to the New Zealand Prime Minister chastising him about New Zealand's "no additional warming" policy seem to have forgotten or are unaware of these four critical facts:

1) The basic science of global mixing of greenhouse gases;

2) New Zealand's emissions profile is dominated by agricultural emissions because it has already mostly decarbonised its energy sector;

3) Fossil fuel-sourced methane emissions cancel out any reductions in livestock emissions and will continue to do so for the foreseeable future; and that,

4) It is easy and cheap, even profitable, for the fossil fuel industry to greatly reduce its methane emissions by good house-keeping

Mr Luxon rightly rejected the Open Letter allegations, telling the authors to turn their attention to other countries with higher-emissions agriculture. A better rebuttal would have been to state that:

"Fossil fuel methane emissions have always greatly exceeded livestock emissions and will continue to do so for the foreseeable future, so there is no justification for spending taxpayer's money on pointless research into futile and economically damaging livestock emission reduction strategies. Methane emissions from fossil fuels should be targeted instead."

Unfortunately Ministry for Primary Industry officials did not give this type of advice to the Prime Minister. They also appear to have failed to keep up with the 29-year history of fossil fuel methane emission under-reporting and its fundamental impact on livestock methane emissions policy (a 30-minute literature search for them and the Open Letter authors). Nor have they appeared to have considered whether or not the predicted 10% livestock emission reductions (3-4 Mt p.a.), achieved at a higher cost to taxpayers ($85-$113 per tonne with $339 million) than NZU carbon credits (currently $58 per unit), will actually contribute to a net global reduction in methane emissions. Or whether the further $155 million (grand total $123-$165 per tonne) will be value for money for New Zealand.

In short, no.

But they were all deceived.....

Nobody seems to have highlighted these simple methane emission facts on the international stage, nor at International Panel on Climate Change (IPCC) meetings. Instead, it appears that most academics and politicians have been taken in by a cynical carbon-con which holds that livestock emissions are contributing significantly to dangerous climate change and that research needs to be done to reduce those emissions for the good of the planet, gas-lighting the agricultural sector. Even the IPCC has been misled (as we see from the Open Letter), since the reduction of livestock emissions is included in Paris Climate Agreement requirements for net zero commitments, when fossil fuel-sourced emissions are the real (and easy-to-fix) methane problem.

Bad advice leads to bad policy and law and bad outcomes. There have even been absurd suggestions that farmers should destock to reduce methane emissions, reducing world protein supplies and farmer incomes. Unnecessary and futile destocking will create significant losses for food producers and consumers in the first and second worlds, and will make subsistence farmers in third world countries even poorer.

Why is the whole world off-track with livestock emissions?

Suffocating levels of fossil fuel industry propaganda continue to deceive and misdirect the world audience with deceptive messaging on the actual existence and causes of dangerous climate change. A mixture of part truths (depending on context), and out-right lies are presented:

• Fossil fuel development is well-established, will meet your future energy needs, is sustainable, and will make you rich

• Clean energy can't do what fossil fuels do

• Clean energy technologies don't work and will damage the environment

• It's too expensive and will take too long to change to clean energy

• Climate change is a hoax and not that bad anyway

One example of how effective this lobbying is can be seen with the 2021 Global Methane Pledge, where New Zealand is a signatory. Methane abatement commitments under the Pledge include 195 nations and cover 80% of oil and gas emissions. However, no meaningful reductions have occurred in the past four years. The fossil fuel industry continues to exert its extraordinary lobbying power globally, with more industry lobbyists at the 2024 COP29 (annual IPCC climate conference) in Baku, Azerbaijan, than representatives from scientific institutions, indigenous communities and vulnerable nations (Mongabay 2024). It is not surprising that fossil-fuel industry pitches and influence on politicians are delaying effective climate action.

The fossil fuel industry is a sunset industry under pressure for its very survival this century. It is conducting a desperate but effective rear-guard action to maintain its dominance over nations and governments because clean energy is now significantly cheaper than dirty energy (IEA 2025), and most people recognise that fossil fuel emissions are driving dangerous climate change.

China and Germany are the world's most prominent investors and producers of renewable energy solutions. Their technologies are having global impact releasing affordable clean energy. Scientists have established a causal link between energy company emissions and US$ 28 trillion in climate damage, possibly exposing energy companies to legal action. In Europe last summer, 16,500 deaths were attributed to climate change-induced extreme heat (Bloomberg 17.09.25). Oil prices are going below break-even level of $USD60 per barrel as society transits away from fossil fuels. These are all existential threats to fossil fuel-based energy companies.

It's a pity that they are not using their gigantic technical and financial resources to lead the transition to clean energy, which after all is better for their customers and staff*, less likely to attract litigation, and would ensure their business' sustainability for the rest of the 21st Century and into the 22nd.

*Note: Diesel exhaust is a Class 1 carcinogen = plutonium, and petrol Class 2A = glyphosate herbicide (IARC 2025)

Why exactly is livestock methane reduction research futile?

• No net reduction of global methane emissions achieved

• Any reductions immediately cancelled out by increasing fossil fuel methane emissions

• Risks to animal health as their digestive systems are interfered with

• Irrational proposals to reduce or abandon livestock farming

What should be done instead?

(1) Re-deploy the scientists

New Zealand leads the 68-nation Global Research Alliance on Agricultural Greenhouse Gases. Now that it is proven by IEA figures that livestock emissions reduction research is futile, it is morally bound to advise the GRA to refocus on agricultural climate change adaptation research. This new direction should concentrate on providing solutions for farmers having to adapt to droughts, floods, heat stress on animals, and less pasture production among other things. For example, scientists and engineers could be re-directed to work on water harvesting, drought-resistant pasture types, soil health improvement with less water, super-efficient irrigation systems, accurate forecasting of extreme weather events, clean energy power on-farm (eg. solar), retrofitting vehicles and machinery to run on clean energy sources, and so forth.

(2) Take natural livestock emissions out of the Paris Climate Agreement

A parallel better investment for New Zealand would be to develop some diplomatic bottle and lead the 68 nations into lobbying the IPCC to remove natural livestock emissions from the Paris Climate Agreement. Then the world could focus more effectively on reducing the true sources of dangerous climate change and pay no attention to those who want to keep putting out the fire with gasoline, or who claim there is no fire. New Zealand could show the way by conducting an independent audit of fossil fuel facilities (paid for by their owners) to ensure that all methane leaks and emissions are stopped.

Otherwise, money spent on livestock methane emission reduction research is like the emissions themselves, just a waste gas blown fore and aft into the wind....

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*Susan Harris is Principal Scientist at GreenXperts Limited, a New Zealand-based sustainability consultancy involved in numerous carbon and land management projects. Susan was on the science team that helped the New Zealand Government create the New Zealand Emissions Trading Scheme. Susan worked on emission factors with other colleagues at that time.