This paper presents a “roadmap” towards achieving net zero in global food systems by 2050 - a plan which has recently been called for by institutional investors. The authors explore 64 pathways to net zero based on implementing varying levels of four major food systems interventions: increasing production efficiency through shifting to low-emissions practices; sequestering carbon in croplands and grasslands; changing diets to reduce the global production of protein from livestock; and adopting a diverse range of “new-horizon” - i.e. emerging - technologies such as methane inhibitors and perennial row crops.
The figure below shows the 64 scenarios, which were built by combining various different levels of each of the four intervention categories: for example (in green) shifting agricultural production to the 10th, 20th, 30th or 40th percentile of emissions intensity of practices currently used worldwide.
Image: Figure 3, Costa et al.
In eight of the scenarios, net zero can be reached through only using existing low emissions agricultural practices (shown in green above; data on the percentile distribution of emissions for different food types is taken from Reducing food’s environmental impacts through producers and consumers) and through land-based carbon sequestration (specifically agroforestry, soil organic carbon in crops and pasture soils and biochar; shown in orange above; data taken from Land-based measures to mitigate climate change: Potential and feasibility by country). Net zero can be reached here because more ambitious levels of both of these interventions are assumed to be applied (within the theoretical estimates of their potential)..
A further eight scenarios also rely on dietary change, shown in blue above - specifically, reductions of up to 50% on FAO projections of consumption of meat and dairy in 2050.
The remaining 48 scenarios would additionally require varying levels of emissions reduction from new-horizon technologies, shown in yellow above. Note that these values do not appear to be based on direct estimates of the emissions reduction potentials of specific technologies - rather, they show how much more work would have to be done by these emerging technologies if emissions cuts from the other three interventions are not sufficient alone to meet net zero. The authors state “there is no silver bullet, and a combination of actions should therefore be targeted to increase the feasibility of achieving net-zero emission [food systems] by 2050.”
The authors present a roadmap for the next three decades, which in brief recommends:
- By 2030, implement cost-effective measures against deforestation and land conversion, along with existing technologies to make the production of beef, milk, rice and maize more efficient; scale these measures up by 2040.
- Sequester 1.7, 3.5 and 5.2 GtCO2 annually by 2030, 2040 and 2050, respectively, using agroforestry, biochar, and improved management of crops (tillage and cover crops) and pasture (rotational grazing and fertilisation).
- By 2040, scale up renewable energy, improve fuel efficiency, promote the circular economy and peri-urban agriculture, and encourage partial dietary shifts away from livestock products and towards plant-based foods in high- and middle-income countries.
- From 2040 to 2050, develop new technologies to reduce food system emissions, such as feed additives for livestock production.
The roadmap is presented in the figure below.
Image: Figure 4, Costa et al. Roadmap for food systems net zero emissions by 2050.
Note that emissions calculations for livestock and rice production were based on the GWP* method, using 2020 as a base year for comparison. Read more about GWP* in the TABLE explainers Agricultural methane and its role as a greenhouse gas and Methane and the sustainability of ruminant livestock, and watch Event recording: Does methane from livestock matter?.
Food systems (FSs) emit ~ 20 GtCO2e/y (~ 35% of global greenhouse gas emissions). This level tends to raise given the expected increases in food demands, which may threaten global climate targets. Through a rapid assessment, evaluating 60+ scenarios based on existing low-emission and carbon sequestration practices, we estimate that intensifying FSs could reduce its emissions from 21.4 to − 2.0 GtCO2e/y and address increasing food demands without relying on carbon offsets (e.g., related to afforestation and reforestation programs). However, given historical trends and regional contexts, a more diverse portfolio of practices, including diet shifts and new-horizon technologies, will be needed to increase the feasibility of achieving net-zero FSs. One likely pathway consists of implementing practices that shift food production to the 30th-percentile of least emission-intensive FSs (~ 45% emissions reduction), sequester carbon at 50% of its potential (~ 5 GtCO2e/y) and adopt diet shifts and new-horizon technologies (~ 6 GtCO2e/y). For a successful transition to happen, the global FSs would, in the next decade (2020s), need to implement cost-effective mitigation practices and technologies, supported by improvements in countries’ governance and technical assistance, innovative financial mechanisms and research focused on making affordable technologies in the following two decades (2030–2050). This work provides options and a vision to guide global FSs to achieving net-zero by 2050.
Costa, C., Wollenberg, E., Benitez, M., Newman, R., Gardner, N. and Bellone, F., 2022. Roadmap for achieving net-zero emissions in global food systems by 2050. Scientific Reports, 12(1), pp.1-11.
Read the full paper here. See also the TABLE explainer How can we reduce food-related greenhouse gas emissions?