Opinion Piece: Zeroing in on Net-Zero

A recent editorial in New Scientist magazine [1], ‘Net-zero action’ has started me pondering.

As the article quite rightly points out, the term net-zero and the science behind it has become commonplace. Most businesses now profess their “net-zero by…” strategies and in many cases “net-zero by 2050” is trumpeted, with the underlying message that “we’re doing our bit - problem solved.”

But as the editorial points out net-zero is essentially a cop out. Originally intended as a solution for industries that could not fully decarbonise their activities, it has now become a tax wheeze: “for executives with an eye on the next quarter, net-zero offers clear appeal.”

Net-zero will be achieved by:

offsetting the offending carbon, in most cases by planting trees which will take many years to absorb significant amounts of carbon (assuming that they survive in drought conditions or flooding)
or by removing it from the atmosphere, using technology which has not yet been fully developed
or by simply not producing it in the first place!

But net-zero strategies are being used to allow business as usual. For example, both Shell and BP have recently announced plans to grow their natural gas businesses; which in the opinion of at least one researcher is a “scientifically incoherent” strategy. Until more CO2 is being removed than emitted, temperatures will continue to rise and climate disasters, such as the crazy temperatures being experienced in parts of southern Europe this week, will become commonplace.

And it is very easy to pass the blame onto big business as we sit snug and warm in our poorly insulated houses or travel overseas! I recently had cause to book a flight to New Zealand. Ignoring both the hypocrisy in my decision and my reasons for going there, I thought I would investigate the offsetting scheme offered by Air New Zealand. For a little over £50 I was offered the opportunity to offset the 3.5 tonnes of CO2e my flight would generate. The methodology behind this offsetting included the use of ‘sustainable’ aviation fuel, certified reforestation and planting native trees in Aotearoa. All highly laudable and better than offering nothing but also guilty of the offsetting greenwash outlined above. I accept it would be better that I didn’t go; but paying the money and taking their offset option is surely preferable to doing nothing? But the arrival of net-zero will not be very much progressed by my gesture (and the plane will depart whether I am on board or not!).

Partly as a conscience assuaging strategy, my wife and I own and manage a hectare or so of woodland in west Wales. About half of this is mature wood, rich in oak, beech and dying ash. (Sadly ash dieback has become a significant issue so that in the area we are actively planting, we have had to stop growing ash.) My research indicates [2] that our mature woodland is a significant carbon store of several hundred tonnes but relatively little, perhaps 1-2 tonnes, is added each year. In contrast the new plantings will sequester much more carbon as they grow into mature trees, but this will take 20-40 years. And new trees die (around 5%, excluding ash), need weeding until established and can be subject to drought (but to date, this has not been a major problem in west Wales!).

Bracken

A more biodiverse environment, compared to the original bracken infested bank, has been created but I suspect the bracken, which can exceed two metres in height before dying back each autumn, is the more efficient carbon sequester in the short term. And ironically, the species that has proven to be the most efficient, as judged by mass of wood developed over the ten years since planting? Non-native eucalyptus!

This confirms, by personal experience, the premise of the New Scientist editorial; tree planting is a delayed method of removing carbon from the atmosphere. We have to rapidly reduce emissions as well as adopt offsetting and carbon removal strategies if we are to attain net zero in time to safely limit rising temperatures.

I recently completed the Vet Sustain/VetSalus Sustainable Food and Farming course [3]. This excellent course provides a broad overview and much detail on the issues relating to net-zero and food production from animals. For my project, which is a voluntary conclusion to the course, I elected to model a route for a hypothetical grass based New Zealand dairy farm towards net zero. My paper was totally superficial; a detailed analysis would have been way beyond the required project length and the hours I had available. So I chose to use a commercial available calculator provided by the New Zealand government [4].

Only a few strategies provided routes to possible progress : nitrogen use and stocking rates were steadily reduced thus freeing up land for, you’ve guessed it, tree planting. Once again, the delays and risks implied in widespread tree planting became obvious. If biodiverse NZ native species were employed, the carbon sequestration rate was initially at least, even slower than non-native conifers. My hypothetical dairy farm achieved net zero by reducing its herd size from 418 to 325, thus freeing up some 40 hectares for tree planting, while increasing productivity per cow and investing in new technology. The productivity increase would, in part, have resulted from improvements in animal health, emphasising the importance of veterinarians in sustainable animal farming systems. But once again this is a slow route to carbon removal from the atmosphere and, in contravention of the Paris COP agreement, reduces food production. And financially, despite the savings on reduced inputs, like fertiliser, the farm has lost significant income and profitability. There are no net carbon surpluses here, which might attract carbon credits either. The development of the best on farm strategy is confusing and complex. A timely path to net-zero status, which employs offsetting, will not be possible for many farming businesses.

In conclusion, net-zero strategies undoubtedly have an important role to play in assisting the quest to keep the increase in our planet's temperature below 2C. (For 1.5 C is now surely unattainable?) But net-zero strategies alone are clearly not enough, and furthermore, dangerously provide a smokescreen, no doubt generated by a raging forest fire, behind which businesses and individuals can hide.

As Johnathon Freedland recently wrote in The Guardian [5]:

“…the climate crisis itself is made by human beings – which is simultaneously enraging and encouraging. Enraging, because it is born of a greed that puts gargantuan profit ahead of a habitable planet. Encouraging, because most problems made by human beings can be fixed by them.”

All is not yet lost. But the role of education, positive communication and leadership around these important issues has never been more urgent. This is core business for VetSalus - if you are not already actively involved, now might be a good time to step forward? Find out more about our work at : www.vetsalus.com

Lewis Griffiths

Chair VetSalus - July 2023

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