The industrial food system is responsible for around one-third of human produced greenhouse gas (GHG) emissions. These emissions come from fertilizer and pesticide industries, the agricultural production industry, and the food distribution industry, all of which rely heavily on the energy sector. By far the biggest contributor is agricultural production, which accounts for up to 86% of the food system’s emissions. Methane that results from submerged rice paddies accounts for about 10% of this total, while the burning of savannahs for agricultural land conversions is responsible for 5%. At 40%, the single largest generator of agricultural production emissions are livestock belches.
We waged wars over bird poop. Now we have to fight to regulate gassy cows.
Emissions trends from the global agriculture industry are no laughing matter. Nitrous oxide, a gas that results from the volatilization of nitrogen fertilizer, joins methane as one of the most potent greenhouse gases. Overall agriculture-related emissions have doubled in the past 50 years. From 2001 to 2011, emissions from livestock increased by 14% and fertilizer emissions grew by 37%. The Food and Agriculture Organization (FAO) anticipates the challenge of feeding 9 billion people by 2050 will represent an additional 30% emissions increase at a time where decreasing emissions is of paramount importance.
The World Resources Institute (WRI) predicts that these increases in emissions will be driven by population growth and shifts in dietary preferences in developing countries, namely Asia and sub- Saharan Africa. As these countries seek to emulate the meat-heavy lifestyle of the developed world, the demand for products with high carbon footprints is likely to increase.
The FAO reports that, in 2011, Asia was the largest generator of agriculture-related GHG outputs (44% of global total). The Americas were next (25%), followed by Africa (15%), Europe (12%), and Oceania (4%). Looking at these emissions on a per capita basis drastically changes regional orders. Oceania ranks worst in agriculture emission efficiency, at an average around 5 tonnes of GHG equivalents per capita. This is mainly due to Australia’s gigantic livestock herds. The Americas again occupy the second spot (1.3 tonnes / capita), followed by Europe (0.86 tonnes / capita), Africa (0.7 tonnes / capita), and Asia (0.5 tonnes / capita). The latter trend emphasizes the need to focus not only on food production, but also on the efficient usage of our agricultural resources.
December’s United Nations Conference on Climate Change will attempt to set legally binding universal agreements on initiatives to mitigate and adapt to climate change. Given the food industry’s sizeable contribution to greenhouse gas emissions, concrete solutions on how to improve global food systems will have to be articulated at all stages of the farm-to-fork system.
The Intergovernmental Panel on Climate Change’s recent report (IPCC AR5) found that a combination of supply and demand-side initiatives can reduce emissions by up to 80% by 2030. GHG reductions are likely to be largest from initiatives enacted at the consumer level. Changing consumption patterns by reducing food waste and by shifting diets away from meat-heavy meals could have substantial impacts on our atmosphere. From the supply side, mitigation efforts involve more efficient utilizations of agricultural inputs (fertilizers and livestock feeds), and improved management practices – such as conservation tillage and rotational grazing. Restoration agriculture and managing crop and pasture land to sequester carbon are also promising win-win mitigation techniques. From an energy perspective, investing in renewables and, when applicable, adopting biofuels can also lower farmland footprints.
Data availability remains a huge challenge to the achievement of these emission reductions. A majority of farmers don’t track their emissions due to a combination of resources, lack of awareness, and availability of simple and standard measurement methods. This last issue is particularly challenging. Discrepancies in measurement standards and assumptions may have underestimated nitrous oxide emissions from fertilizer applications in the United States Corn Belt by up to 40%. It is vital that we develop scale-appropriate methods for helping the food industry track their emissions as our understanding of agriculture GHG dynamics evolves. Measuring cow flatulences may not be the sexiest thing to put on a resume, but its policy implications can have drastic implications for the fight against climate change.