Toward Net Zero

In a separate Brief, we’ve outlined the particular challenges associated with residual emissions, and commented on questions of which emissions are ‘hard to abate’. We argued that elite arguments of technical complexity, and purported economic hardship for key sectors, get the lion’s share of attention in defining ‘hardest to abate’. This in turn sets the stage for what scientifically is an unacceptably high level of residual emissions that would have to be removed or ‘netted out’, with the ‘hard to abate’ debate thus becoming a proxy permission for continued emissions. That Brief also referenced the different between ‘survival’ and ‘luxury’ emissions. We address those challenges more deeply here.

Food production, food security, and ‘hard to abate’ emissions

Actually, a very large proportion of food production emissions are not that hard to abate. A huge literature exists of opportunities for emission reductions through increased equity in landholding patterns; agroecological transitions; de-commodification and re-localization of food production; reducing animal agriculture production volumes as a result of both lowered per-animal emissions and dietary shifts. Clearly, much more could be done to bring agriculture-sector emissions down as close as possible to ‘real zero’. That is the necessary direction of travel in agriculture. [See CLARA’s Missing Pathways, Section 3, at pp. 25-35].

Since a dramatic reduction in the agricultural sector’s emissions is needed, correlated with a shift to agroecological approaches, it’s first worth asking to what extent spending priorities in agricultural research and development reflect that need. Unfortunately, as recently shown for Africa by CLARA member Biovision and IPES, most R&D spending is for refining agroindustrial approaches, rather than in reducing reliance on synthetic nitrogen fertilizers and improving adaptive capacities at the farmstead level. 

While there’s little dispute that historically the availability of cheap nitrogen fertilizers has been a boon for yields—the so-called ‘Green Revolution’—this has been achieved at a very high cost for people and planet. Some of the most damaging greenhouse gases—with global warming potentials far exceeding that of carbon dioxide—result from the production and use of synthetic nitrogen fertilizers. Further, the startling productivity gains associated with earlier applications of synthetic fertilizers have now vanished, replaced by diminishing returns and greatly increased environmental damage, in particular degradation of soils. Similarly, the expanded use of herbicides associated with ‘no-till’—one of the agroindustrial approaches embedded in the now-discredited idea of ‘climate smart agriculture’—has allowed for the evolution of ‘superweeds’ that similarly indicate the need for a paradigm shift. Ending dependence on such inputs will be required to abate a significant fraction of the 23% of current anthropogenic emissions that still come from agriculture. 

Synthetic Nitrogen Fertilizers and Net Zero

Will emissions from synthetic nitrogen fertilizers be a significant part of the volume of residual emissions in [say] 2030? Probably. At the farm level, pursuing agroecological transitions, there are cost-effective substitutes for fertilizer—such as rebuilding soil health through intensive cover crop use and rotational grazing of livestock. 

But the sheer volume of emissions associated with food production in the 21st century indicates that there will be residual emissions in agriculture, even if per-hectare emissions are decreased, until an agroecological transition is completed. 

So—‘easy to abate’ at a farm-practices level, and also through some technological substitutions. But the overall agroecological transition itself will take time, and every 0.1°C rise in global temperature will make it more difficult. Difficult not just in relation to impacts on yields and the resilience of necessary support systems, but also because sequestration capacity in nature diminishes with temperature rise. And this says nothing about the necessary revamp of the actual food systems within which production and consumption takes place, which implicates other sectors. 

Residual emissions associated with food production and global food security are more critical for survival than is [say] air travel or other luxury emissions. We will likely need to use some ‘atmospheric space’ to maintain on-farm yields, including from a greater diversity of crops, while pursuing landscape level changes that increase resilience. We’ll need to safeguard food security while making the break away from high-GHG-input agricultural approaches. None of this will be easy; but, in the words of the great American poet Wendell Berry, ’its hardship is its possibility’.

In the final analysis, we need to turn the ‘hard to abate’ question around, and ask: what helps to guarantee food security? What can be achieved in terms of equitable, sustainable development associated with a particular volume of residual emissions? Otherwise, ‘sustainable development’ becomes merely an attribute within overall setting approaches to net zero.

https://www.biovision.ch/fileadmin/pdf/Infografiken/AE_KW_IG-und-Inti_E.pdf