The ways in which we produce food and manage our lands are responsible for almost a third of global greenhouse gas emissions along the entire supply chain. A new study led by the Potsdam Institute for Climate Impact Research (PIK) has found that just shrinking the size of our current food system will not substantially cut emissions. Instead, the experts argue that fundamental transformations in the very nature of the global food system are necessary in order to fix these problems.
“That means on the one hand that people consume what they need in terms of nutritional requirements, curb food waste, and eat a more balanced diet, with much more vegetables and less animal products,” explained study lead author Benjamin Bodirsky, a senior scientist at PIK.
“On the other hand, a qualitative transformation means more efficiency, hence producing food in a less-polluting way: smarter dosing of fertilizers or planting higher-yield crops. Also, carbon pricing could help steer farmers towards lower-emission agricultural practices, because emitting less means paying less. Put together, this could drastically reduce greenhouse gas emissions.”
Dr. Bodirsky and his colleagues performed an in-depth review of degrowth proposals and created a set of scenarios which they fed into a food and land systems computer simulation to explore their effect on the food system. These analyses revealed that the current food system is unsustainable for any society, regardless of economic growth rates.
According to the simulations, simply curbing growth in rich countries would not lead to sizable sustainability benefits in the food system. Moreover, financial transfers from richer to poorer countries within the current development paradigms could even increase emissions, since carbon-intensive diet changes are most pronounced when countries move from low to medium incomes.
However, when the researchers included consumption changes and efficiency gains incentivized by the price of carbon, the results pointed towards improved nutritional outcomes for all consumers, as well as lower greenhouse emissions.
“For the food sector, we can say that a certain degree of degrowth would be the result of the sustainable transformation, not the starting point,” said study co-author Hermann Lotze-Campen, an agricultural economist at PIK. “So basically this is not really about less but about different growth.”
Since a sustainable food system transformation that takes into account all costs to the environment would lead to a slight increase in food prices, any such changes must be accompanied by a comprehensive policy mix of smart taxing schemes, social compensation for carbon dioxide pricing, and international transfers. Finally, making agriculture more climate friendly – by controlling nitrogen flows in croplands for, instance – would entail further investments. According to the experts though, all these costs will likely be offset by the urgently needed restoration of crucial ecosystem services.
The study is published in the journal Nature Food.