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Opinion: When it comes to feeding the world in the face of climate change - solutions are offered, but what are the implications of those solutions, Dr Jacqueline Rowarth asks.
"Code Red for humanity" is an attention-grabbing headline. The official title from the International Panel for Climate Change (IPCC) is "AR6 Climate Change 2021: The Physical Science Basis". It simply doesn't have the same impact. But whatever the heading, the fundamental message is the same: action is required.
In response, the message from Greenpeace New Zealand was the same as every time there is a global or national report on climate or environment - ban synthetic nitrogen, reduce the number of cows and move to organic regenerative agriculture.
Greenpeace issued its statement in response to the IPCC report at 8.22pm on August 9.
The United Nations commented at 8.29pm, and RNZ was broadcasting headlines from 9pm.
Greenpeace was clearly poised to respond, and though the general direction was predictable, other organisations took more time to digest the content. And think about the implications.
It is important to acknowledge that Greenpeace's three-pronged suggestion would work to decrease emissions if enacted globally. The decrease would not, however, be for the reasons believed.
1. Banning synthetic nitrogen would result in a marked reduction in food availability. Synthetic nitrogen has been estimated by Massachusetts Institute of Technology researchers to feed half the current global population.
2. Reducing cow numbers would reduce diet quality. Animal protein contains essential amino acids that are not provided by vegetable protein in the quantity required without consumption of excess calories and excretion of excess nitrogen (with its own GHG impact).
3. Regenerative organic agriculture cannot produce enough food for the global population, now or predicted – because it doesn't use synthetic nitrogen. See point one.
In making the statements, Greenpeace NZ is focusing on New Zealand without apparently recognising that in a world of food shortage, we would not be isolated from the needs of other countries.
War is generally about scarce resources (and religion). Climate change, brought about by release of fossil fuel and the greenhouse gases (GHG) associated with modern living, is a global problem.
Most people recognise that it is population growth and lifestyle choices that are driving climate change. We want to be warm, eat good food, get about easily and have things.
Reducing animals, most of which graze on land unsuitable for anything but pasture or are fed waste from biofuel and alcohol distilleries, would increase the price of animal-based food globally, putting it beyond the reach of the people who need it for bones and muscle development.
Dairy cows in New Zealand are particularly efficient, producing less than 0.04 per cent of the world's GHG and provide the essential amino acids of approximately 1 per cent of the global population. They are fed high-quality pasture and managed for health and welfare.
A change to organic regenerative agriculture in New Zealand would increase the GHG footprint per kg of product.
This is because pasture quality cannot be maintained under long-grazing of a mixed herbal pasture – the research has been done.
The United Nations methane report suggested that improving feed quality to animals and improving the genetics of the animals themselves (their ability to turn forage into meat and milk) and increasing their longevity, would reduce their impact. New Zealand has been doing what is recommended for decades.
The big impact of a switch to regenerative organic agriculture is, however, the reduction in yield.
Globally yields from organic farms, whether regenerative or not, are less than 60 per cent of a conventional farm over a decade.
Listen to Jamie Mackay interview Dr Jacqueline Rowarth on The Country below:
The reduction isn't apparent initially because nutrients are mineralised from the organic matter (OM) by micro-organisms. Carbon dioxide is released to the atmosphere from the OM and the OM content decreases unless manure (containing organic matter) is imported.
Not acknowledged is that the manure doesn't always come from organic sources - it has involved synthetic nitrogen. This is termed green-laundering.
Plant-based protein has been offered as an alternative to animal protein, but leguminous crops such as soybeans require land.
They also require irrigation and agrichemicals including nitrogen fertiliser if the goal is high yields (minimising the amount of land needed for a certain quantity of food).
For those who think that cultured animal protein can fill the void, ponder this: The Good Food Institute (a group promoting cultured food) has calculated that to fill only 10 per cent of the world's current meat market would require 4000 facilities each housing 130 bioreactor lines and vats (for fermentation) of a size that has not yet been developed.
The estimate of cost has reached US$1.8 trillion...
And overlooked appears to be the fact that the bioreactors are fuelled with sugar which comes from crops requiring land and agrichemicals including nitrogen.
Further, the GHG associated with cultured meat will last for very much longer in the atmosphere than the methane associated with animals.
Research by University of Oxford physicists has calculated that the effect of cultured meat is greater than that of efficiently managed animals.
There are no easy answers. Greenpeace's solution for New Zealand would have unintended consequences for the world, just like the use of fossil fuel.
Dr Jacqueline Rowarth, Adjunct Professor Lincoln University, is a farmer-elected director of DairyNZ and Ravensdown. The analysis and conclusions above are her own. jsrowarth@gmail.com
One adult died at the scene and three people suffered minor to moderate injuries.