environment

Methane targets could’ve been tougher on farmers

Farming groups criticised the Government for going too far with shrinking New Zealand’s methane emissions, but they might have been worse off, short term, had it gone with calculations made for the Environment Commissioner. Using Simon Upton’s graphs as a policy guide could have seen short-term cuts twice as deep as what the Government's proposing. In the heated debate about cutting methane, the PCE's numbers have been shorn of crucial details.

It could be read as a gently coded “be careful what you wish for”.

Farming groups have criticised as too strict the Government’s proposed cuts to methane, which, in New Zealand, largely arises from animal burps.

But the source of some of the material for their argument - the Environment Commissioner - has clarified his methane calculations in a follow-up note. Cuts to methane could have been much steeper in the short-term under his modelling: twice as steep as the Government's 2030 proposal for a 10 percent cut.

Methane from farm animals is in the news, again, because a Government bill due to go before a select committee in June proposes reducing gas from cow and sheep guts, and landfills, by a combined 10 percent from 2017 levels by 2030, with reductions of between 24-47 percent by 2050. The targets come with the proviso that the independent Climate Change Commission will be able to adjust them based on new technology and other future developments. New Zealand’s other major gases - carbon dioxide and nitrous oxide (largely from animal wee on pasture) - will need to fall to net zero by 2050, meaning any ongoing emissions by then will need to be countered by carbon sinks.

The methane targets were attacked from all sides as being too tough (by some farming groups) and too soft (by some environmental groups) – with green groups questioning the modest near-term target, and farmers’ groups focusing on the steeper, 2050 cuts.

Beef + Lamb and DairyNZ put out press releases saying the 2050 range was too draconian because it was outside the range of numbers that were calculated for the Parliamentary Commissioner for the Environment, Simon Upton, as being necessary to stabilise warming from methane. Modelling carried out for Upton found that 10-22 percent cuts by 2050 would be enough to flat-line the share of global warming caused by Kiwi cow and sheep burps, with greater cuts by 2100. Although Upton has repeatedly said those numbers were not a policy recommendation, they were naturally embraced as a science-supported target by farming groups, who were possibly relieved by their relative modesty.

When the Government announced the 24-47 percent range, Beef + Lamb said: “The Government’s decision appears to fly in the face of international scientific evidence, which supports reducing and stabilising methane by 10-22 percent as equivalent to net carbon zero."

DairyNZ said: “While we can support much of what is in the Zero Carbon legislation, we will be pushing for the range to be reviewed and aligned with the recommendations made by the Parliamentary Commissioner for the Environment, of 10-22 per cent reduction in methane."

Somewhere in the process, though, important details behind Upton's numbers got lost, and he has now clarified those in a note showing farmers might be worse off under his scenarios.

Upton supplied a chart and explanatory note to Newsroom showing why his calculations aren’t directly comparable with the Government's – and that following his modelling for a maximum 2C warmer world would mean animal methane dropped by 20 percent by 2030, double the Government’s 2030 target.

Here’s why.

The Government is aiming for New Zealand to behave in a way that’s consistent with a maximum of 1.5C global warming, following a bracing IPCC report showing the human toll of higher heating - not least for Pacific countries and the world’s food farmers. 

The toughest end of Upton’s range assumed countries were on track to stay under 2C, at best. Staying under 1.5C would require deeper cuts than the 22 percent posited at the top of the PCE's range.

Upton had asked experts to model a very specific thing: what would it take to be able to claim that New Zealand's animal methane wasn’t worsening global warming, it was simply chugging along making about the same contribution to climate change as it was making in 2016 (this concept prompted lots of policy arguments about whether this was a good and fair goal, but let's leave those aside for now).

The first reason adopting the trajectories Upton modelled might not be better for farmers is this: If his modelling had been adopted as policy, and if the world was on track to have a better-than-even chance of staying within 2C, his modelling assumed almost all of the 22 percent reduction in methane occurring by 2050 would have already happened by 2030 - in fact, it would mostly happen in the first few years. While the long-term methane cuts would be smaller than the Government’s proposed 2050 range, the short-term shrinkage would be double that Government's proposed 10 percent target - 20 percent less methane by 2030.

At the easier, 10 percent end of Upton’s range, the world would be on track to seriously overshoot 2C. Meanwhile: “If other countries took greater action to reach a 1.5 degrees Celsius temperature goal, it would be expected that reductions greater than 22 percent would be required to achieve no additional warming as a result of New Zealand’s biological methane from agriculture,” according to Upton's clarifying note.

There’s another reason the Government’s proposal might be seen as preferable to farmers, at least in the short-term. Upton’s numbers included only methane produced by animals, while the Government’s targets also include methane from landfills. While methane from waste is only about 12 percent of our methane emissions to agriculture’s 85 percent, including waste in the targets may buy time for tackling agriculture. If landfill gas can be caught and reduced more quickly and easily than cow burps - as the bioenergy industry is already suggesting it can - the portion of the Government’s 2030 target falling on farmers may be less than a 10 percent reduction implies. It remains to be seen in the policy and practical details.

There’s also another set of relevant numbers: those in the IPCC report on staying within 1.5C. Upton's note points out that the Government’s near-term methane target is also more lenient than that range, of 11-30 percent cuts, although, on the other hand, the Government's bill also proposes getting nitrous oxide to net zero, which is more ambitious than the IPCC's modelling. Beef + Lamb has indicated its members are willing to pursue net zero nitrous oxide, likely using tree planting to help them.

Here's what the PCE's follow-up note says of the various methane numbers:

"The emissions trajectories implied by my note and the Government’s bill have different shapes. The trajectories in my note were not adjusted to meet any technological or economic constraints. They imply around a 20 percent reduction from the 2016 level by 2030. For comparison, the IPCC central range of trajectories aligned with a 1.5 degrees Celsius goal imply an 11-30 percent reduction in biological methane emissions from agriculture by 2030 compared to the 2010 level. The bill proposes a 10 percent reduction from the 2017 level by 2030.”

There's a final set of numbers that Upton's note and clarification doesn't mention: the report by the Biological Emissions Reference Group, whose members include Beef + Lamb NZ, DairyNZ, Fonterra, Federated Farmers and MPI. Those calculations concern, not what's necessary, but what's feasible.

BERG's modelling showed that combining all the options for cutting farm emissions could reduce farms’ gaseous output by between 10-21 percent by 2030, and 22-48 percent by 2050, compared to business-as-usual. DairyNZ and Beef + Lamb NZ told Newsroom their concerns were that those BERG estimates relied on new technology becoming available, namely a methane inhibitor for dosing cows and sheep to make them burp less methane. The BERG report said there was “high confidence” an inhibitor would be ready to be used on farms by 2050 and, if it happens, the two farming groups agreed they would be happy to see an accordingly stricter target on methane.

Of course, Upton’s calculations were never intended to be followed to the letter as government policy. His original accompanying note said 20 percent cuts by 2030 likely wouldn’t happen in the real world, despite what the modelling implied. He seems to have approached the exercise as a way to get some interesting numbers out there ahead of the bill's introduction, allowing people to say with confidence, for example, that merely flat-lining cow burp emissions at today’s levels would not be enough to flatten the global warming impact from our dairy industry. Government targets - unlike gas models - factor in economic, social, fairness and other factors. But before anyone can argue that the “science” supports their preferred target, we'll need to check we're comparing apples with apples. Or yoghurt with yoghurt. Or burps with belches.

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