Will agriculture be the sacrificial lamb to achieve carbon zero?

The clouds of change are forming over the agricultural livestock that are the backbone of the New Zealand economy. Photo / Supplied

Mike Cranstone, president of Whanganui Federated Farmers, shares his thoughts on battling climate change.

Our politicians have been quick to sign New Zealand's commitment to the latest lofty targets set at the recent COP 26 climate meeting in Glasgow. But Minister James Shaw has failed to show the real leadership needed to represent New Zealand as an agriculture-dependent economy.

This leadership was required not just for New Zealand, but for the many developing nations whose economies are also reliant on agriculture. The message needed to explain the different contributions to global warming of methane, whether it's emitted from burning fossil fuel or from belching livestock.

The warming impact of methane from the burning of fossil fuels is very significant, as it is releasing the potent warming gas that has been locked away underground for thousands of years.

Biogenic methane, which is belched from livestock, is part of a carbon cycle. Methane is a short-lived gas that breaks down in the atmosphere after 12 years. It breaks down into carbon dioxide and water, in almost the exact proportions that are removed from the atmosphere by the photosynthesis of the grass eaten by the livestock.

With stable livestock numbers, the methane concentration is in equilibrium, with virtually no additional warming. The industrial nations have little motivation to acknowledge biogenic methane because their agricultural emissions are insignificant compared with their emissions from energy and transport.

Real leadership at Glasgow would have seen New Zealand sharing our research and this would provide a pathway for emerging economies to be able to sign up to climate goals without decimating their agricultural reliant economies.

Biogenic methane makes up only 4 per cent by volume of New Zealand's gas emissions, but with simplistic accounting metrics dating back to 1990, they are represented as 35 per cent of NZ's liability.

The issue is the outdated Global Warming Potential (GWP100) metric fails to account that methane is a short-lived gas that breaks down in 12 years, compared with CO2, which continues warming every year for its 1000-year lifespan in the atmosphere. The world's efforts are all about limiting global warming to 1.5 degrees, so we should be using the updated GWP* metric that measures the warming effect of GHGs.

The stakes are huge; ignoring the accurate science on biogenic methane will impose a massive cost to New Zealand. The Government has conceded it will have to purchase carbon credits from offshore to offset domestic emissions.

Wrongly accounting for biogenic methane at the current carbon price of $65/ton creates an additional annual liability of $2.4 billion every year. That is equivalent to building a new hospital every year throughout New Zealand, but instead Minister Shaw is committing us to pay an overseas financier for carbon credits grown on another country's productive land.

This is not New Zealand avoiding its obligations, it is about real leadership and promoting the knowledge from New Zealand-led global research on agricultural emissions.

Maybe this government has a longer-term plan, but it has not talked to NZ about how we as a country are going to survive if we lose our main income by decimating agriculture. We have all seen what happened when we lost tourism due to Covid-19. We can't just live on borrowed money.

Just as increasing methane concentrations creates significant warming, a reduction has a significant cooling effect. Cutting livestock numbers is being relied upon to provide the "cooling" while the country struggles to contain increasing emissions from the transport and electricity sectors. Basically, this government is relying on slashing livestock numbers to meet its ambitious GHG reduction targets.

Agriculture, particularly the hill country sheep industry, will be the sacrificial lamb in this government's quest to be carbon zero by 2050.

The inequity is that the Government has no intentions of acknowledging farmers or the wider industry for this cooling contribution. There is evidence that cutting livestock numbers has been their plan for some time; current proposals do not allow farmers to offset their livestock methane emissions by planting trees, and the minister asked the Climate Change Commission in its report earlier this year what scale of methane reductions would be required to balance carbon emissions from fossil fuel use.

New Zealanders' standard of living is so dependent on agriculture with it contributing 70 per cent of our export income, but this government plans to decimate parts of it in its quest for net-zero bragging rights.

The release of the He Waka Eke Noa, the agricultural report, this month needs to be challenged by all New Zealanders, as it will have ramifications for this country's ability to maintain high standards of healthcare, education, and other public services.