David Clark, Federated Farmers’ Mid Canterbury chair is fed up with the methane myth:
As a farmer I am fed up with being vilified and our industry accused of being the primary contributor to climate change in New Zealand.
He’s not alone. I haven’t encountered such strength of feeling among farmers since the ag-sag of the 1980s.
The myth is that agricultural gases, primarily methane, make up 48.1 per cent of this country’s emissions profile. That is nothing more than a politically and socially convenient half-truth/untruth.
So here are established, scientific facts pertinent to the Zero Carbon Bill and the Emissions Trading Scheme:
• A pre-existing and stable level of greenhouse gases in our atmosphere is required to maintain our temperature levels and is essential to life on earth.
• The Paris Accord calls for countries to take steps to limit global warming to 2 degC and preferably 1.5 degC above pre-Industrial temperatures.
The Paris Accord also stipulates that climate change mitigation should not come at the expense of food production.
• NZ has set a target of Zero Carbon by 2050 – no mandated reduction in gross carbon emission, just an aspiration to offset by forestry plantings so that carbon emitted will be in balance with carbon sequestered.
• Total methane emissions in NZ have increased 6.2 per cent from 1990 to 2017 (they have been declining since 2006). Agricultural production has doubled in this time.
• The ZCB has an aspiration of reducing methane by up to 47 per cent by 2050.
• Methane is a short-lived gas that originated from CO2 absorbed by the growing grass and when belched by livestock rapidly breaks down into CO2 again to complete the cycle. No additional carbon enters the atmosphere.
Fossil fuel carbon has not been circulating in the atmosphere for thousands or millions of years, but once burnt will circulate in the atmosphere for centuries to come, with constant additional warming effect.
• The key objective is to limit any further warming.
Clark says representing methane on the same graph as fossil carbon and stating that agricultural gases are 48.1 per cent of our emissions is simply wrong and does not recognise the cyclical nature of methane.
He then shows why:
Methane is a short lived gas, known as a “flow gas” which rapidly breaks down compared to carbon, which is known as a “stocks gas”.
So let’s represent methane as water and carbon as small stones. I have a bucket that is the atmosphere and the level inside the bucket is the global warming effect.
I have a centimetre of water in the bucket, which has a small hole in the bottom of it.
I start tipping cupfuls of water into the bucket. So long as I do not tip in water faster than it drains from the hole, the level does not increase.
It would be wrong to count the number of cupfuls put into the bucket, only correct to pay attention to the change in level. The number of cupfuls has absolutely no relationship to the level in the bucket.
If I take the same bucket and start dropping small stones into it, none of which fit out the hole, every stone is additional and the bucket gradually fills up. The total number of stones added has a direct correlation to the number of stones in the bucket.
Methane and carbon are water and stones. So long as stock numbers remain static, or more correctly the feed fed to livestock remains static, the emission of methane today replaces the methane that degraded today. The cycle stays in balance.
Every gram of carbon emitted from a power station, factory, car, aeroplane or any other part of our life adds to all of the carbon previously emitted from all sources.
The only way of reducing that carbon is to effectively bury it by absorption into soil by plants.
Our Government need to stop telling the methane myth and stop counting the water and the stones as if they were equal. They are not.
Net methane makes up only a very small portion of NZ’s total emissions. Our farmers are being asked to reduce methane emissions way beyond the equivalent of “Zero Carbon” and are being vilified in the process.
The current fixation on methane is a dangerous, politically convenient distraction taking the focus of the enormous task of eliminating our reliance on carbon for our modern existence.
Not only is it dangerous and a political distraction, the government’s determination to impose unrealistic methane reduction targets on farmers would at the very best have no impact on the global methane emissions, and almost certainly worsen them because New Zealand accounts for such a small percentage of the world’s farm stock.
New Zealand has about 6.5m dairy cows and 3.6m beef cattle.
That’s a lot of cattle when you compare it with the human population of fewer than 5 million people.
But how does that compare with other countries?
India has 305,000,000 cattle – 30.44% of the world total.
Brazil has 232,350 – 23.19%.
China has 96,850 – 9.6%
The USA has 94,399,00 – 9.42%
The EU has 88,445,000 – 8.83%
Argentina has 53,765,000 – 5.37%
Australia has 25,500,000 – 2.55%
Russia has 18,380,000 – 1.83%
Mexico has 16,584,000 – 1.66%
Turkey has 14,500,000 – 1.45%
Uruguay has 11,754,000 – 1.17%
Canada has 11,625,000 – 1.16%
New Zealand has 10,082,000 – 1.01%
We have a lot of sheep and cattle per head of population but that’s only because we have so few heads.
This puts into perspective the calls from radical and not so radical environmentalists for New Zealand to cull its dairy herd.
Half of 1.01% is not very much in global terms.
When it is better environmentally for the people in Ireland, the country with the second-most efficient dairy production to drink milk from New Zealand, the most efficient producers, the aim ought to be to produce more milk here, not to cut production.
The case for cuts doesn’t add up in economic, social or environmental terms, nor is it based on science.