Sir Peter reports on the mitigation of agricultural greenhouse gas emissions

Arguments for focusing on carbon dioxide and nitrous oxide and giving less emphasis to methane are counter-productive, Sir Peter Gluckman says in a letter to Prime Minister Jacinda Ardern which accompanies his final report as the Prime Minister’s chief science advisor. Therefore he does not favour avoiding a focus on methane, despite the challenges such a focus creates.

He also says it it unrealistic to imagine a GHG-neutral profile from agriculture without offsets in various forms.

Those views are reflected in Sir Peter’s final report, which has been published today.  It is entitled Mitigating agricultural greenhouse gas emissions: Strategies for meeting New Zealand’s goals

The report’s conclusions are driven by consideration of the highly variable nature of New Zealand geography, soil types, climate, and farming systems, Sir Peter says in his letter to Ms Ardern.

This heterogeneity creates challenges for generalisation and identifying the best ways to proceed. There are actions that farmers can now take that will have some impact on GHG emissions, and some near-term technologies that could have further effect if further developed for and adopted into NZ farming systems. But

” … there is no current or foreseeable methodology that will provide an accurate measure of GHG emissions on an individual farm, nor of what any particular mitigation measure might achieve at a farm level. This has major implications for how to proceed.

“Emissions at an individual farm level can only be estimated through proxy measures using scientific models such as OVERSEER, which is subject to some debate over its utility as a direct regulatory tool across a range of farm types, and has other issues that currently limit its usefulness. Taking these factors into account, one option that seems feasible is to use a ‘farm plan’ approach whereby a farmer, with expert advice and science-based input, identifies mitigation strategies he/she will be accountable for adhering to.

“Compliance or otherwise with an appropriate farm plan could extend to other dimensions of environmental management and to animal welfare and could be linked to any market or regulatory incentive scheme. Such an approach would require greater focus on the skillset of appropriately accredited farm advisors.”

The report highlights where scientific and policy focus should be concentrated, and outlines actions in terms of farmer and industry practices as well as research and investment to speed up the development of the most promising abatement technologies and better quantification of GHG emissions.

Sir Peter says:

“In some cases, issues of social acceptance and regulatory approvals will need to be addressed pre-emptively. It is likely that significant trade-offs will be required and there will be conflicting views: these should be acknowledged.”

Sir Peter recalls in the letter his first meeting with Ms Ardern to discuss her priorities for his Office after she became Prime Minister. She asked him to report back on what the agricultural sector could do over the near and intermediate term to reduce its greenhouse gas emissions, enabling  New Zealand to track more effectively towards meeting its commitments under the Paris Agreement on climate action, and ultimately, the government’s carbon-neutral goal.

The letter says:

“New Zealand is seen internationally as an efficient producer of high quality food and will remain a major agricultural producer into the foreseeable future. However, maintaining agriculture’s central role in our export economy will require the sector to be increasingly sympathetic to the environment. Part of that must include reducing its contributions to greenhouse gas (GHG) production, and this could be done over time probably without substantive impacts on productivity or economic returns. But doing so will likely require some complex trade-offs, consideration of new technologies, and significant changes in farming practice and land use.

“In order to fully understand the landscape, my Office convened two large expert group meetings of governmental, farming and food sector stakeholders and have met with many experts from relevant sectors in smaller groups to discuss the opportunities and challenges in this complex area.

“My Office canvassed expert opinion on specific mitigation options and we have reviewed the scientific literature, including draft copies of analyses commissioned by the Biological Emissions Reference Group (BERG), a joint government and sector working group (due for public release in September 2018). I understand that the Productivity Commission, the Parliamentary Commissioner for the Environment and Interim Climate Change Committee (with whom I have met) will be providing Government with further evidence and/or advice on these and related issues in the future.”

Sir Peter’s report aims to present a high-level perspective on what would be needed to achieve meaningful reductions in greenhouse gas emissions, and greater offsets, in the agricultural sector. It integrates the work of various research efforts in New Zealand and abroad, briefly reviews available on-farm mitigation options, highlights emerging opportunities, and identifies gaps in knowledge or other barriers that need to be overcome if agriculture is to be included in the New Zealand Emissions Trading Scheme (ETS), or any other policy mechanism.

The executive summary says agriculture – in contrast to the power and transport sectors – has fewer options to make large emissions reductions quickly and cost-effectively.

“Obligating farmers to reduce their emissions should not impose a disproportionate burden on them relative to their international competitors, nor relative to other sectors within New Zealand. There are no zero-emission strategies for biological GHGs, yet there are many reasons to act aggressively to reduce their emissions. This goes beyond arguments of short-lived versus long-lived gases; there are also strong market and reputational reasons for driving down agricultural emissions while making farms more efficient and sustainable.

“Methane and nitrous oxide are the main GHG emissions occurring on farms. Methane, derived mainly from enteric fermentation in ruminant livestock, is a short-lived gas, but one that has contributed most to the sector’s increasing emissions since 1990.

“Although methane does not accumulate in the atmosphere like CO2 does, it has potent effects on near-term warming, and this potency increases with increasing rates of methane emissions over time. While noting that methane emissions from agriculture cannot, and need not be, reduced to zero, reducing global methane emissions quickly will impact the peak warming temperature and the rate at which CO2 emissions need to be reduced.

“The metrics used to account for the different gases are important, particularly if biological GHGs are to be included in the ETS or similar mechanism at any level, as different metrics have implications for carbon, nitrous oxide and methane budgets.

“Strategies exist now that can help reduce biological GHGs, but currently, individual strategies are only expected to have modest effects on total emissions reduction, and there are trade-offs between possible options that will require careful consideration at an individual farm situation.”

The main strategies relate to:

• On-farm land-use decisions that reduce GHG emissions per unit of land area or increase carbon sinks – including forestry and other tree plantings, and horticulture blocks.

• Feeding practices, grazing and pasture management – including forage selection and the balance between stocking rates per hectare and individual performance per animal.

• Animal husbandry including breeding for high genetic merit in terms of breeding, productivity and emissions profiles.

• Animal housing and effluent management

• Precision-farming techniques – including irrigation and fertiliser management

“Apart from substantial land-use change, reducing livestock numbers and afforestation, the report says, the main opportunities to reduce emissions significantly will depend on technological innovations; for example the development of market-acceptable nitrification inhibitors, and to rumen methane inhibitors such as 3NOP for use in pastoral systems.

“Developing a methanogen-inhibiting vaccine holds theoretical promise for reducing methane emissions across all ruminant livestock systems but no proof-of-concept in animals yet exists.

“A mission-led approach to research will continue to be needed. Social science research is also required to understand how best to encourage early adopters and to enhance uptake of effective strategies across the sector. For the longer term, unravelling the regulatory and social licence issues around the use of new and evolving technologies will be critical for continuing scientific advancement as part of the national effort to reduce New Zealand’s largest sources of GHGs.

Despite the many scientific, economic and implementation challenges, failure to take actions within the agricultural sector will not only be costly to those farmers who find themselves unprepared for change, it will also ultimately be costly to New Zealand.”

NZIAHS forum reminder: The NZIAHS forum, to be held in Science House in Wellington on Friday, is titled Agriculture and the Emissions Trading Scheme (ETS): How do we enable farmers to respond?

Source: Office of the Prime Minister’s Chief Science Advisor

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New Zealand’s zero carbon bill: much ado about methane

Massey University applied mathematics professor Robert McLachlan, in an article posted on Sciblogs examines the prospect of New Zealand becoming the first country in the world to put a price on greenhouse gas emissions from agriculture.

Work in shaping zero carbon legislation is under way and the public has been invited to contribute in a consultation exercise led by Minister for Climate Change James Shaw.

More than 4,000 submissions have been received, with a week to go.

The crunch point is whether agriculture should be part of the country’s transition to a low-emission economy.

Professor McLachlan writes:

Many of the 16 questions in the consultation document concern the proposed climate change commission and how far its powers should extend. But the most contentious question refers to the definition of what “zero carbon” actually means.

The government has set a net zero carbon target for 2050, but in the consultation it is asking people to pick one of three options:

  • net zero carbon dioxide – reducing net carbon dioxide emissions to zero by 2050
  • net zero long-lived gases and stabilised short-lived gases – carbon dioxide and nitrous oxide to net zero by 2050, while stabilising methane
  • net zero emissions – net zero emissions across all greenhouse gases by 2050.

The three main gases of concern are carbon dioxide (long-lived, and mostly produced by burning fossil fuels), nitrous oxide (also long-lived, and mostly produced by synthetic fertilisers and animal manures) and methane (short-lived, and mostly produced by burping cows and sheep). New Zealand’s emissions of these gases in 2016 were 34 million tonnes (Mt), 9Mt, and 34Mt of carbon dioxide equivalent (CO₂e), respectively.

All three options refer to “net” emissions, which means that emissions can be offset by land use changes, primarily carbon stored in trees. In option 1, only carbon dioxide is offset. In option 2, carbon dioxide and nitrous oxide are offset and methane is stabilised. In option 3, all greenhouses gases are offset.

Gathering support

Opposition leader Simon Bridges has declared his support for the establishment of a climate change commission. DairyNZ, an industry body, has appointed 15 dairy farmers as “climate change ambassadors” and has been running a nationwide series of workshops on the role of agricultural emissions.

Earlier this month, Ardern and the Farming Leaders Group (representing most large farming bodies) published a joint statement that the farming sector and the government are committed to working together to achieve net zero emissions from agri-food production by 2050. Not long after, the Climate Leaders Coalition, representing 60 large corporations, announced their support for strong action to reduce emissions and for the zero carbon bill.

However, the devil is in the detail. While option 2 involves stabilising methane emissions, for example, it does not specify at what level or how this would be determined. Former Green Party co-leader Jeanette Fitzsimons has argued that methane emissions need to be cut hard and fast, whereas farming groups would prefer to stabilise emissions at their present levels.

This would be a much less ambitious 2050 target than option 3, potentially leaving the full 34Mt of present methane emissions untouched. Under current international rules, this would amount to an overall reduction in emissions of about 50% on New Zealand’s 1990 levels and would likely be judged insufficient in terms of the Paris climate agreement. This may not be what people thought they were voting for in 2017.

Why we can’t ignore methane

To keep warming below 2℃ above pre-industrial global temperatures, CO₂ emissions will need to fall below zero (that is, into net removals) by the 2050s to 2070s, along with deep reductions of all other greenhouse gases. To stay close to 1.5℃, the more ambitious of the twin Paris goals, CO₂ emissions would need to reach net zero by the 2040s. If net removals cannot be achieved, global CO₂ emissions will need to reach zero sooner.

Therefore, global pressure to reduce agricultural emissions, especially from ruminants, is likely to increase. A recent study found that agriculture is responsible for 26% of human-caused greenhouse emissions, and that meat and dairy provide 18% of calories and 37% of protein, while producing 60% of agriculture’s greenhouse gases.

A new report by Massey University’s Ralph Sims for the UN Global Environment Facility concludes that currently, the global food supply system is not sustainable, and that present policies will not cut agricultural emissions sufficiently to limit global warming to 1.5℃ above pre-industrial levels.

Finding a way forward

Reducing agricultural emissions without reducing stock numbers significantly is difficult. Many options are being explored, from breeding low-emission animals and selecting low-emission feeds to housing animals off-pasture and methane inhibitors and vaccines.

But any of these will face a cost and it is unclear who should pay. Non-agricultural industries, including the fossil fuel sector, are already in New Zealand’s Emissions Trading Scheme (ETS) and would like agriculture to pay for emissions created on the farm. Agricultural industries argue that they should not pay until cost-effective mitigation options are available and their international competitors face a similar cost.

The government has come up with a compromise. Its coalition agreement states that if agriculture were to be included in the ETS, only 5% would enter into the scheme, initially. The amount of money involved here is small – NZ$40 million a year – in an industry with annual export earnings of NZ$20 billion. It would add about 0.17% to the price of whole milk powder and 0.5% to the wholesale price of beef.

The ConversationHowever, it would set an important precedent. New Zealand would become the first country in the world to put a price agricultural emissions. Many people hope that the zero carbon bill will represent a turning point. It may even inspire other countries to follow suit.

The article was originally published on The Conversation and can be read HERE. 

Greenhouse gas experts provide an understanding of the methane debate

Parliament will decide on the pathway for tackling our greenhouse gases (GHGs) after the current consultation on the proposed Zero Carbon Bill, the New Zealand Agricultural Greenhouse Gas Research Centre observes in a post on its website.

The Bill presents three broad scenarios –

* net zero carbon dioxide by 2050, which would reduce net carbon dioxide emissions in New Zealand to zero by 2050 (but would not set a target for other gases like methane or nitrous oxide);

* net zero long-lived gases (mainly carbon dioxide and nitrous oxide) and stabilisation of emissions of short-lived gases (mainly methane) by 2050; and

* net zero emissions by 2050, which would reduce net emissions across all GHGs to zero by 2050.

These aren’t “either/or” alternatives, the research centre says. The choice can sit anywhere along the spectrum spanned by those targets.

The term “stabilisation” does not necessarily mean doing nothing. It could also mean reducing methane emissions to a stable level lower than today.

As the co-ordination centre for research aimed at developing technologies and practices to reduce the full suite of GHGs generated by agriculture, the NZAGRC is offering information on the science of GHGs to help inform the debate.

Here’s what it says…

Continue reading

Separating cars from cows in climate policy

Long-lived atmospheric pollutants that build up over centuries, like CO2, should be treated differently from short-lived pollutants which disappear within a few years, like methane, an international team of researchers is arguing.

The collaboration involved Victoria University of Wellington researchers.

The Government should pay heed to the team’s recommendation before further regulating New Zealand’s biggest industries in the agricultural sector.

Current policies tend to treat all pollutants as equivalent, the researchers say. But methane should be treated differently and a separate climate change policy is needed to regulate methane emissions.

Scimex reports a press statement from Victoria University of Wellington HERE.

A new collaboration between researchers at Victoria University of Wellington, the Universities of Oxford and Reading in the United Kingdom and the Centre for International Climate Research in Norway shows a better way to think about how methane might fit into carbon budgets, the statement says.

“Current climate change policy suggests a ‘one size fits all’ approach to dealing with emissions,” says Professor Dave Frame, head of Victoria University’s Climate Change Research Institute.

“But there are two distinct types of emissions, and to properly address climate change and create fair and accurate climate change policy we must treat these two groups differently.”

The two types of emissions that contribute to climate change can be divided into ‘long-lived’ and ‘short-lived’ pollutants.

“Long-lived pollutants, like carbon dioxide, persist in the atmosphere, building up over centuries,” says Dr Michelle Cain, from the Oxford Martin School at the University of Oxford.

“The carbon dioxide created by burning coal in the 18th century is still affecting the climate today.

“Short-lived pollutants, like methane, disappear within a few years. Their effect on the climate is important but very different from that of carbon dioxide, yet current policies treat them all as equivalent.”

The research collaboration proposes a new approach to climate change policy that would address the effects of these different emissions.

This would be particularly relevant to New Zealand agriculture.

“We don’t actually need to give up eating meat or dairy to stabilise global temperatures,” says Professor Myles Allen from the University of Oxford, who led the study.

“We just need to stop increasing emissions from these sources. But we do need to give up dumping carbon dioxide into the atmosphere. Climate policies could be designed to reflect this.”

Under current policies, industries that produce methane are managed as though that methane has a permanently worsening effect on the climate, says Professor Frame.

“But this is not the case. Implementing a policy that better reflects the actual impact of different pollutants on global temperatures would give agriculture a fair and reasonable way to manage their emissions and reduce their impact on the environment.

“Implementing a policy like this would show New Zealand to be leaders and innovators in climate change policy. It would also help New Zealand efficiently manage their emissions, and could even get us to the point where we manage them so well we stop contributing to global climate change at all.”

The research can be seen in npj/Climate and Atmospheric Science HERE.

Source: Scimex

Technical working group calls for urgent action on climate change

A report from the Climate Change Adaptation Technical Working Group urges better planning and resourcing and strong leadership to prepare New Zealand for a warmer, wetter and wilder future.

The report, released today, makes 21 major recommendations as a starting point.

It says the Government should urgently set about first identifying what needs to be done and who does what along with undertaking a countrywide risk assessment to inform it.

It also suggests the Local Government Act 2002 be changed to specify climate change adaptation as a function of local government and arm local authorities with a clearer mandate.

Strong leadership is called for, too – the Government should make it clear to the public that climate change is a priority, from a review of policy and legislation to factoring climate impacts into government and council procurement processes.

Climate Change Minister James Shaw issued a press statement (HERE) to accompany the release of the recommendations.

The group’s Co-Chair, Dr Judy Lawrence, says in the statement that even if the world stopped all greenhouse gas emissions today, our climate would still change for centuries.

“Previous emissions take time to show their impact and are long lasting. We are already seeing the effects of climate change with sea level rise, more floods and hotter temperatures and we can expect further losses and damage,” says Dr Lawrence.

“We need robust data to assess our risks and see where and who is most vulnerable and exposed. This will enable us to put a national plan into action which is independently monitored and reported on.

“Adaptation needs to be funded so that there are incentives for people and organisations to take adaptive action. All of this work needs to be supported by strong leadership.

“The group has conveyed its expectation that the government will put in place a coordinated set of measures. These will enable New Zealand to reduce its exposure and vulnerability to the changing climate.”

Mr Shaw said becoming climate-resilient was a significant challenge.

“But it’s clear from CCATWG’s report that with the right plans and tools in place, we have a greater chance of managing the transition,” says Mr Shaw.

“There is new money in Budget 2018 for resourcing the Government’s climate change priorities.

“I see risk assessment as a priority and I intend to bring options to Cabinet soon for a decision on how and when to do a risk assessment.

“In the coming weeks we will be asking New Zealanders how they see New Zealand adapting to the effects of climate change as part of the Zero Carbon Bill consultation.

“We are all in this together and we have a responsibility to future generations to make changes now and build on what has been started. This will provide a framework for the future. I urge everyone to be part of the conversation.

“Taking early action in the right areas is likely to avoid the need for more abrupt action later,” says Mr Shaw.

The report can be read HERE.

People can register to have their say on how New Zealand becomes climate resilient as part of the Zero Carbon Bill HERE.

Royal Society posts video discussion among experts on land use and climate change

A video recording of a panel discussion which looks at the implications for land use of responses to climate change, in this country and around the globe, has been posted on the Royal Society Te Apārangi’s website.

The discussion, Land use and climate change: new pressures and new possibilities?, is chaired by Veronika Meduna, NZ editor of The Conversation.

Issues of current land use and climate change are explored with a panel of international contributors – their expertise is in global food security, sustainable resource management, renewable energy, sustainable development, and economics relating to climate change.

The event was opened by the Intergovernmental Panel on Climate Change Working Group III co-chairs Professor Jim Skea (UK) and Dr Youba Sokona (Mali), who were at the IPCC lead authors’ meeting on Land Use and Climate Change in Christchurch in March.

Speakers were:

Professor Tim Benton (UK)
Professor and Dean of Strategic Research Initiatives at the University of Leeds and Distinguished Fellow at the Royal Institute of International Affairs, Chatham House, London. Formerly the Champion of the UK’s Global Food Security programme.

Professor Annette Cowie (AUS)
Principal Research Scientist -Climate, NSW Department of Primary Industries
Research experience includes sustainability assessment and greenhouse gas accounting in agriculture and forestry; investigating key aspects of soil carbon dynamics; life cycle assessment of forestry, bioenergy and biochar systems.

Dr Fatima Denton (Ethiopia)
Head of the African Climate Policy Centre, Director of the UN Economic Commission for Africa’s Special Initiatives Division.
In 2016 she was nominated by the Borlaug Dialogue International Symposium, as one of the Women Leaders Driving Agricultural Transformation in Africa.

Associate Professor Anita Wreford (NZ)
Agribusiness and Economics Research Unit, Lincoln University (NZ)
Applied economist specialising in responses to climate change, Anita is a lead author for the IPCC Working Group III.

The event was hosted by the University of Canterbury in partnership with the IPCC, the Ministry for the Environment, Te Rūnanga o Ngāi Tahu, The New Zealand Agricultural Greenhouse Gas Research Centre and Royal Society Te Apārangi.

Comprehensive resources on the implications of climate change, the impact on health, and mitigation options for New Zealand can be found at the Royal Society Te Apārangi website HERE. 

Source:  Royal Society Te Apārangi

Canterbury University scientists involved in intermittent rivers study

University of Canterbury scientists are part of a global research collaboration into the environmental impacts of dry riverbeds, with their findings published today in a new paper in one of the world’s top scientific journals (see AgScience report HERE).

New Zealand researchers, Professor of Freshwater Ecology Angus McIntosh and Dr Catherine Febria, of the School of Biological Sciences, UC College of Science, have been part of a global team from 22 countries evaluating what happens to plant litter that falls into in river beds when they are dry (i.e. not flowing).

They co-authored the paper titled ‘A global analysis of terrestrial plant litter dynamics in non-perennial waterways’ which was published today in Nature Geoscience.

“People might feel that a pile of plant litter accumulating in a dry river bed couldn’t possibly contribute to global climate warming, but the surprising reality is it very likely is,” Professor McIntosh says.

The contributions of drying rivers haven’t been included in global carbon accounting previously and their CO2 effects  could be significant.

“This is especially important because, surprisingly, intermittent streams and drying rivers are thought to include more than 50% of the river length world-wide,” he says.

Dr Febria says it is known that when rivers dry up fish and insects die, and the whole food web of the river collapses.

“However, we haven’t previously appreciated the significance of all the decomposition that happens when the water comes back. The amount of carbon dioxide released in many cases is huge,” she says.

“We should all care about this because carbon dioxide in our atmosphere is the driver of global climate warming.

“Our research indicates that increasingly drying rivers, along with other land use changes, are contributing to global climate warming. Moreover, climate warming in many places like Canterbury is predicted to increase the frequency and magnitude of drought which could also cause more river drying.

“That is a really worry because that could form a positive feedback cycle by releasing even more carbon dioxide.”

This is the first piece of research published from this collaborative study involving 94 international partners from 22 countries studying the dry beds of 212 rivers from round the world, including Canterbury.

Until recently, drying and intermittent rivers had been largely ignored. This global study is beginning to reveal they really are very important and should not be ignored.

Such extensive global research efforts have traditionally been rare. That a very large group of researchers from around the world, led by a group in France, have come together to contribute is really quite significant, Professor McIntosh says.

He didn’t expect the magnitude of emissions to be so high. Therefore the findings should force a rethink of how the global carbon models are made so that they include CO2 emissions from intermittent rivers.

Source: University of Canterbury